1 /*
2 * Copyright (c) 1997, 2015, 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).
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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,
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/connode.hpp"
29 #include "opto/convertnode.hpp"
30 #include "opto/divnode.hpp"
31 #include "opto/machnode.hpp"
32 #include "opto/movenode.hpp"
33 #include "opto/matcher.hpp"
34 #include "opto/mulnode.hpp"
35 #include "opto/phaseX.hpp"
36 #include "opto/subnode.hpp"
37
38 // Portions of code courtesy of Clifford Click
39
40 // Optimization - Graph Style
41
42 #include <math.h>
43
44 //----------------------magic_int_divide_constants-----------------------------
45 // Compute magic multiplier and shift constant for converting a 32 bit divide
46 // by constant into a multiply/shift/add series. Return false if calculations
47 // fail.
48 //
49 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
50 // minor type name and parameter changes.
51 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
52 int32_t p;
53 uint32_t ad, anc, delta, q1, r1, q2, r2, t;
54 const uint32_t two31 = 0x80000000L; // 2**31.
55
56 ad = ABS(d);
57 if (d == 0 || d == 1) return false;
58 t = two31 + ((uint32_t)d >> 31);
59 anc = t - 1 - t%ad; // Absolute value of nc.
60 p = 31; // Init. p.
61 q1 = two31/anc; // Init. q1 = 2**p/|nc|.
62 r1 = two31 - q1*anc; // Init. r1 = rem(2**p, |nc|).
63 q2 = two31/ad; // Init. q2 = 2**p/|d|.
64 r2 = two31 - q2*ad; // Init. r2 = rem(2**p, |d|).
65 do {
66 p = p + 1;
67 q1 = 2*q1; // Update q1 = 2**p/|nc|.
68 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
69 if (r1 >= anc) { // (Must be an unsigned
70 q1 = q1 + 1; // comparison here).
71 r1 = r1 - anc;
72 }
73 q2 = 2*q2; // Update q2 = 2**p/|d|.
74 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
75 if (r2 >= ad) { // (Must be an unsigned
76 q2 = q2 + 1; // comparison here).
77 r2 = r2 - ad;
78 }
79 delta = ad - r2;
80 } while (q1 < delta || (q1 == delta && r1 == 0));
81
82 M = q2 + 1;
83 if (d < 0) M = -M; // Magic number and
84 s = p - 32; // shift amount to return.
85
86 return true;
87 }
88
89 //--------------------------transform_int_divide-------------------------------
90 // Convert a division by constant divisor into an alternate Ideal graph.
91 // Return NULL if no transformation occurs.
92 static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) {
93
94 // Check for invalid divisors
95 assert( divisor != 0 && divisor != min_jint,
96 "bad divisor for transforming to long multiply" );
97
98 bool d_pos = divisor >= 0;
99 jint d = d_pos ? divisor : -divisor;
100 const int N = 32;
101
102 // Result
103 Node *q = NULL;
104
105 if (d == 1) {
106 // division by +/- 1
107 if (!d_pos) {
108 // Just negate the value
109 q = new SubINode(phase->intcon(0), dividend);
110 }
111 } else if ( is_power_of_2(d) ) {
112 // division by +/- a power of 2
113
114 // See if we can simply do a shift without rounding
115 bool needs_rounding = true;
116 const Type *dt = phase->type(dividend);
117 const TypeInt *dti = dt->isa_int();
118 if (dti && dti->_lo >= 0) {
119 // we don't need to round a positive dividend
120 needs_rounding = false;
121 } else if( dividend->Opcode() == Op_AndI ) {
122 // An AND mask of sufficient size clears the low bits and
123 // I can avoid rounding.
124 const TypeInt *andconi_t = phase->type( dividend->in(2) )->isa_int();
125 if( andconi_t && andconi_t->is_con() ) {
126 jint andconi = andconi_t->get_con();
127 if( andconi < 0 && is_power_of_2(-andconi) && (-andconi) >= d ) {
128 if( (-andconi) == d ) // Remove AND if it clears bits which will be shifted
129 dividend = dividend->in(1);
130 needs_rounding = false;
131 }
132 }
133 }
134
135 // Add rounding to the shift to handle the sign bit
136 int l = log2_intptr(d-1)+1;
137 if (needs_rounding) {
138 // Divide-by-power-of-2 can be made into a shift, but you have to do
139 // more math for the rounding. You need to add 0 for positive
140 // numbers, and "i-1" for negative numbers. Example: i=4, so the
141 // shift is by 2. You need to add 3 to negative dividends and 0 to
142 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
143 // (-2+3)>>2 becomes 0, etc.
144
145 // Compute 0 or -1, based on sign bit
146 Node *sign = phase->transform(new RShiftINode(dividend, phase->intcon(N - 1)));
147 // Mask sign bit to the low sign bits
148 Node *round = phase->transform(new URShiftINode(sign, phase->intcon(N - l)));
149 // Round up before shifting
150 dividend = phase->transform(new AddINode(dividend, round));
151 }
152
153 // Shift for division
154 q = new RShiftINode(dividend, phase->intcon(l));
155
156 if (!d_pos) {
157 q = new SubINode(phase->intcon(0), phase->transform(q));
158 }
159 } else {
160 // Attempt the jint constant divide -> multiply transform found in
161 // "Division by Invariant Integers using Multiplication"
162 // by Granlund and Montgomery
163 // See also "Hacker's Delight", chapter 10 by Warren.
164
165 jint magic_const;
166 jint shift_const;
167 if (magic_int_divide_constants(d, magic_const, shift_const)) {
168 Node *magic = phase->longcon(magic_const);
169 Node *dividend_long = phase->transform(new ConvI2LNode(dividend));
170
171 // Compute the high half of the dividend x magic multiplication
172 Node *mul_hi = phase->transform(new MulLNode(dividend_long, magic));
173
174 if (magic_const < 0) {
175 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(N)));
176 mul_hi = phase->transform(new ConvL2INode(mul_hi));
177
178 // The magic multiplier is too large for a 32 bit constant. We've adjusted
179 // it down by 2^32, but have to add 1 dividend back in after the multiplication.
180 // This handles the "overflow" case described by Granlund and Montgomery.
181 mul_hi = phase->transform(new AddINode(dividend, mul_hi));
182
183 // Shift over the (adjusted) mulhi
184 if (shift_const != 0) {
185 mul_hi = phase->transform(new RShiftINode(mul_hi, phase->intcon(shift_const)));
186 }
187 } else {
188 // No add is required, we can merge the shifts together.
189 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
190 mul_hi = phase->transform(new ConvL2INode(mul_hi));
191 }
192
193 // Get a 0 or -1 from the sign of the dividend.
194 Node *addend0 = mul_hi;
195 Node *addend1 = phase->transform(new RShiftINode(dividend, phase->intcon(N-1)));
196
197 // If the divisor is negative, swap the order of the input addends;
198 // this has the effect of negating the quotient.
199 if (!d_pos) {
200 Node *temp = addend0; addend0 = addend1; addend1 = temp;
201 }
202
203 // Adjust the final quotient by subtracting -1 (adding 1)
204 // from the mul_hi.
205 q = new SubINode(addend0, addend1);
206 }
207 }
208
209 return q;
210 }
211
212 //---------------------magic_long_divide_constants-----------------------------
213 // Compute magic multiplier and shift constant for converting a 64 bit divide
214 // by constant into a multiply/shift/add series. Return false if calculations
215 // fail.
216 //
217 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
218 // minor type name and parameter changes. Adjusted to 64 bit word width.
219 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) {
220 int64_t p;
221 uint64_t ad, anc, delta, q1, r1, q2, r2, t;
222 const uint64_t two63 = UCONST64(0x8000000000000000); // 2**63.
223
224 ad = ABS(d);
225 if (d == 0 || d == 1) return false;
226 t = two63 + ((uint64_t)d >> 63);
227 anc = t - 1 - t%ad; // Absolute value of nc.
228 p = 63; // Init. p.
229 q1 = two63/anc; // Init. q1 = 2**p/|nc|.
230 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|).
231 q2 = two63/ad; // Init. q2 = 2**p/|d|.
232 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|).
233 do {
234 p = p + 1;
235 q1 = 2*q1; // Update q1 = 2**p/|nc|.
236 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
237 if (r1 >= anc) { // (Must be an unsigned
238 q1 = q1 + 1; // comparison here).
239 r1 = r1 - anc;
240 }
241 q2 = 2*q2; // Update q2 = 2**p/|d|.
242 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
243 if (r2 >= ad) { // (Must be an unsigned
244 q2 = q2 + 1; // comparison here).
245 r2 = r2 - ad;
246 }
247 delta = ad - r2;
248 } while (q1 < delta || (q1 == delta && r1 == 0));
249
250 M = q2 + 1;
251 if (d < 0) M = -M; // Magic number and
252 s = p - 64; // shift amount to return.
253
254 return true;
255 }
256
257 //---------------------long_by_long_mulhi--------------------------------------
258 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication
259 static Node* long_by_long_mulhi(PhaseGVN* phase, Node* dividend, jlong magic_const) {
260 // If the architecture supports a 64x64 mulhi, there is
261 // no need to synthesize it in ideal nodes.
262 if (Matcher::has_match_rule(Op_MulHiL)) {
263 Node* v = phase->longcon(magic_const);
264 return new MulHiLNode(dividend, v);
265 }
266
267 // Taken from Hacker's Delight, Fig. 8-2. Multiply high signed.
268 // (http://www.hackersdelight.org/HDcode/mulhs.c)
269 //
270 // int mulhs(int u, int v) {
271 // unsigned u0, v0, w0;
272 // int u1, v1, w1, w2, t;
273 //
274 // u0 = u & 0xFFFF; u1 = u >> 16;
275 // v0 = v & 0xFFFF; v1 = v >> 16;
276 // w0 = u0*v0;
277 // t = u1*v0 + (w0 >> 16);
278 // w1 = t & 0xFFFF;
279 // w2 = t >> 16;
280 // w1 = u0*v1 + w1;
281 // return u1*v1 + w2 + (w1 >> 16);
282 // }
283 //
284 // Note: The version above is for 32x32 multiplications, while the
285 // following inline comments are adapted to 64x64.
286
287 const int N = 64;
288
289 // Dummy node to keep intermediate nodes alive during construction
290 Node* hook = new Node(4);
291
292 // u0 = u & 0xFFFFFFFF; u1 = u >> 32;
293 Node* u0 = phase->transform(new AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
294 Node* u1 = phase->transform(new RShiftLNode(dividend, phase->intcon(N / 2)));
295 hook->init_req(0, u0);
296 hook->init_req(1, u1);
297
298 // v0 = v & 0xFFFFFFFF; v1 = v >> 32;
299 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF);
300 Node* v1 = phase->longcon(magic_const >> (N / 2));
301
302 // w0 = u0*v0;
303 Node* w0 = phase->transform(new MulLNode(u0, v0));
304
305 // t = u1*v0 + (w0 >> 32);
306 Node* u1v0 = phase->transform(new MulLNode(u1, v0));
307 Node* temp = phase->transform(new URShiftLNode(w0, phase->intcon(N / 2)));
308 Node* t = phase->transform(new AddLNode(u1v0, temp));
309 hook->init_req(2, t);
310
311 // w1 = t & 0xFFFFFFFF;
312 Node* w1 = phase->transform(new AndLNode(t, phase->longcon(0xFFFFFFFF)));
313 hook->init_req(3, w1);
314
315 // w2 = t >> 32;
316 Node* w2 = phase->transform(new RShiftLNode(t, phase->intcon(N / 2)));
317
318 // w1 = u0*v1 + w1;
319 Node* u0v1 = phase->transform(new MulLNode(u0, v1));
320 w1 = phase->transform(new AddLNode(u0v1, w1));
321
322 // return u1*v1 + w2 + (w1 >> 32);
323 Node* u1v1 = phase->transform(new MulLNode(u1, v1));
324 Node* temp1 = phase->transform(new AddLNode(u1v1, w2));
325 Node* temp2 = phase->transform(new RShiftLNode(w1, phase->intcon(N / 2)));
326
327 // Remove the bogus extra edges used to keep things alive
328 PhaseIterGVN* igvn = phase->is_IterGVN();
329 if (igvn != NULL) {
330 igvn->remove_dead_node(hook);
331 } else {
332 for (int i = 0; i < 4; i++) {
333 hook->set_req(i, NULL);
334 }
335 }
336
337 return new AddLNode(temp1, temp2);
338 }
339
340
341 //--------------------------transform_long_divide------------------------------
342 // Convert a division by constant divisor into an alternate Ideal graph.
343 // Return NULL if no transformation occurs.
344 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
345 // Check for invalid divisors
346 assert( divisor != 0L && divisor != min_jlong,
347 "bad divisor for transforming to long multiply" );
348
349 bool d_pos = divisor >= 0;
350 jlong d = d_pos ? divisor : -divisor;
351 const int N = 64;
352
353 // Result
354 Node *q = NULL;
355
356 if (d == 1) {
357 // division by +/- 1
358 if (!d_pos) {
359 // Just negate the value
360 q = new SubLNode(phase->longcon(0), dividend);
361 }
362 } else if ( is_power_of_2_long(d) ) {
363
364 // division by +/- a power of 2
365
366 // See if we can simply do a shift without rounding
367 bool needs_rounding = true;
368 const Type *dt = phase->type(dividend);
369 const TypeLong *dtl = dt->isa_long();
370
371 if (dtl && dtl->_lo > 0) {
372 // we don't need to round a positive dividend
373 needs_rounding = false;
374 } else if( dividend->Opcode() == Op_AndL ) {
375 // An AND mask of sufficient size clears the low bits and
376 // I can avoid rounding.
377 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long();
378 if( andconl_t && andconl_t->is_con() ) {
379 jlong andconl = andconl_t->get_con();
380 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) {
381 if( (-andconl) == d ) // Remove AND if it clears bits which will be shifted
382 dividend = dividend->in(1);
383 needs_rounding = false;
384 }
385 }
386 }
387
388 // Add rounding to the shift to handle the sign bit
389 int l = log2_long(d-1)+1;
390 if (needs_rounding) {
391 // Divide-by-power-of-2 can be made into a shift, but you have to do
392 // more math for the rounding. You need to add 0 for positive
393 // numbers, and "i-1" for negative numbers. Example: i=4, so the
394 // shift is by 2. You need to add 3 to negative dividends and 0 to
395 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
396 // (-2+3)>>2 becomes 0, etc.
397
398 // Compute 0 or -1, based on sign bit
399 Node *sign = phase->transform(new RShiftLNode(dividend, phase->intcon(N - 1)));
400 // Mask sign bit to the low sign bits
401 Node *round = phase->transform(new URShiftLNode(sign, phase->intcon(N - l)));
402 // Round up before shifting
403 dividend = phase->transform(new AddLNode(dividend, round));
404 }
405
406 // Shift for division
407 q = new RShiftLNode(dividend, phase->intcon(l));
408
409 if (!d_pos) {
410 q = new SubLNode(phase->longcon(0), phase->transform(q));
411 }
412 } else if ( !Matcher::use_asm_for_ldiv_by_con(d) ) { // Use hardware DIV instruction when
413 // it is faster than code generated below.
414 // Attempt the jlong constant divide -> multiply transform found in
415 // "Division by Invariant Integers using Multiplication"
416 // by Granlund and Montgomery
417 // See also "Hacker's Delight", chapter 10 by Warren.
418
419 jlong magic_const;
420 jint shift_const;
421 if (magic_long_divide_constants(d, magic_const, shift_const)) {
422 // Compute the high half of the dividend x magic multiplication
423 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
424
425 // The high half of the 128-bit multiply is computed.
426 if (magic_const < 0) {
427 // The magic multiplier is too large for a 64 bit constant. We've adjusted
428 // it down by 2^64, but have to add 1 dividend back in after the multiplication.
429 // This handles the "overflow" case described by Granlund and Montgomery.
430 mul_hi = phase->transform(new AddLNode(dividend, mul_hi));
431 }
432
433 // Shift over the (adjusted) mulhi
434 if (shift_const != 0) {
435 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(shift_const)));
436 }
437
438 // Get a 0 or -1 from the sign of the dividend.
439 Node *addend0 = mul_hi;
440 Node *addend1 = phase->transform(new RShiftLNode(dividend, phase->intcon(N-1)));
441
442 // If the divisor is negative, swap the order of the input addends;
443 // this has the effect of negating the quotient.
444 if (!d_pos) {
445 Node *temp = addend0; addend0 = addend1; addend1 = temp;
446 }
447
448 // Adjust the final quotient by subtracting -1 (adding 1)
449 // from the mul_hi.
450 q = new SubLNode(addend0, addend1);
451 }
452 }
453
454 return q;
455 }
456
457 //=============================================================================
458 //------------------------------Identity---------------------------------------
459 // If the divisor is 1, we are an identity on the dividend.
460 Node *DivINode::Identity( PhaseTransform *phase ) {
461 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
462 }
463
464 //------------------------------Idealize---------------------------------------
465 // Divides can be changed to multiplies and/or shifts
466 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
467 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
468 // Don't bother trying to transform a dead node
469 if( in(0) && in(0)->is_top() ) return NULL;
470
471 const Type *t = phase->type( in(2) );
472 if( t == TypeInt::ONE ) // Identity?
473 return NULL; // Skip it
474
475 const TypeInt *ti = t->isa_int();
476 if( !ti ) return NULL;
477 if( !ti->is_con() ) return NULL;
478 jint i = ti->get_con(); // Get divisor
479
480 if (i == 0) return NULL; // Dividing by zero constant does not idealize
481
482 if (in(0) != NULL) {
483 phase->igvn_rehash_node_delayed(this);
484 set_req(0, NULL); // Dividing by a not-zero constant; no faulting
485 }
486
487 // Dividing by MININT does not optimize as a power-of-2 shift.
488 if( i == min_jint ) return NULL;
489
490 return transform_int_divide( phase, in(1), i );
491 }
492
493 //------------------------------Value------------------------------------------
494 // A DivINode divides its inputs. The third input is a Control input, used to
495 // prevent hoisting the divide above an unsafe test.
496 const Type *DivINode::Value( PhaseTransform *phase ) const {
497 // Either input is TOP ==> the result is TOP
498 const Type *t1 = phase->type( in(1) );
499 const Type *t2 = phase->type( in(2) );
500 if( t1 == Type::TOP ) return Type::TOP;
501 if( t2 == Type::TOP ) return Type::TOP;
502
503 // x/x == 1 since we always generate the dynamic divisor check for 0.
504 if( phase->eqv( in(1), in(2) ) )
505 return TypeInt::ONE;
506
507 // Either input is BOTTOM ==> the result is the local BOTTOM
508 const Type *bot = bottom_type();
509 if( (t1 == bot) || (t2 == bot) ||
510 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
511 return bot;
512
513 // Divide the two numbers. We approximate.
514 // If divisor is a constant and not zero
515 const TypeInt *i1 = t1->is_int();
516 const TypeInt *i2 = t2->is_int();
517 int widen = MAX2(i1->_widen, i2->_widen);
518
519 if( i2->is_con() && i2->get_con() != 0 ) {
520 int32_t d = i2->get_con(); // Divisor
521 jint lo, hi;
522 if( d >= 0 ) {
523 lo = i1->_lo/d;
524 hi = i1->_hi/d;
525 } else {
526 if( d == -1 && i1->_lo == min_jint ) {
527 // 'min_jint/-1' throws arithmetic exception during compilation
528 lo = min_jint;
529 // do not support holes, 'hi' must go to either min_jint or max_jint:
530 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
531 hi = i1->_hi == min_jint ? min_jint : max_jint;
532 } else {
533 lo = i1->_hi/d;
534 hi = i1->_lo/d;
535 }
536 }
537 return TypeInt::make(lo, hi, widen);
538 }
539
540 // If the dividend is a constant
541 if( i1->is_con() ) {
542 int32_t d = i1->get_con();
543 if( d < 0 ) {
544 if( d == min_jint ) {
545 // (-min_jint) == min_jint == (min_jint / -1)
546 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
547 } else {
548 return TypeInt::make(d, -d, widen);
549 }
550 }
551 return TypeInt::make(-d, d, widen);
552 }
553
554 // Otherwise we give up all hope
555 return TypeInt::INT;
556 }
557
558
559 //=============================================================================
560 //------------------------------Identity---------------------------------------
561 // If the divisor is 1, we are an identity on the dividend.
562 Node *DivLNode::Identity( PhaseTransform *phase ) {
563 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
564 }
565
566 //------------------------------Idealize---------------------------------------
567 // Dividing by a power of 2 is a shift.
568 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
569 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
570 // Don't bother trying to transform a dead node
571 if( in(0) && in(0)->is_top() ) return NULL;
572
573 const Type *t = phase->type( in(2) );
574 if( t == TypeLong::ONE ) // Identity?
575 return NULL; // Skip it
576
577 const TypeLong *tl = t->isa_long();
578 if( !tl ) return NULL;
579 if( !tl->is_con() ) return NULL;
580 jlong l = tl->get_con(); // Get divisor
581
582 if (l == 0) return NULL; // Dividing by zero constant does not idealize
583
584 if (in(0) != NULL) {
585 phase->igvn_rehash_node_delayed(this);
586 set_req(0, NULL); // Dividing by a not-zero constant; no faulting
587 }
588
589 // Dividing by MINLONG does not optimize as a power-of-2 shift.
590 if( l == min_jlong ) return NULL;
591
592 return transform_long_divide( phase, in(1), l );
593 }
594
595 //------------------------------Value------------------------------------------
596 // A DivLNode divides its inputs. The third input is a Control input, used to
597 // prevent hoisting the divide above an unsafe test.
598 const Type *DivLNode::Value( PhaseTransform *phase ) const {
599 // Either input is TOP ==> the result is TOP
600 const Type *t1 = phase->type( in(1) );
601 const Type *t2 = phase->type( in(2) );
602 if( t1 == Type::TOP ) return Type::TOP;
603 if( t2 == Type::TOP ) return Type::TOP;
604
605 // x/x == 1 since we always generate the dynamic divisor check for 0.
606 if( phase->eqv( in(1), in(2) ) )
607 return TypeLong::ONE;
608
609 // Either input is BOTTOM ==> the result is the local BOTTOM
610 const Type *bot = bottom_type();
611 if( (t1 == bot) || (t2 == bot) ||
612 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
613 return bot;
614
615 // Divide the two numbers. We approximate.
616 // If divisor is a constant and not zero
617 const TypeLong *i1 = t1->is_long();
618 const TypeLong *i2 = t2->is_long();
619 int widen = MAX2(i1->_widen, i2->_widen);
620
621 if( i2->is_con() && i2->get_con() != 0 ) {
622 jlong d = i2->get_con(); // Divisor
623 jlong lo, hi;
624 if( d >= 0 ) {
625 lo = i1->_lo/d;
626 hi = i1->_hi/d;
627 } else {
628 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
629 // 'min_jlong/-1' throws arithmetic exception during compilation
630 lo = min_jlong;
631 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
632 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
633 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
634 } else {
635 lo = i1->_hi/d;
636 hi = i1->_lo/d;
637 }
638 }
639 return TypeLong::make(lo, hi, widen);
640 }
641
642 // If the dividend is a constant
643 if( i1->is_con() ) {
644 jlong d = i1->get_con();
645 if( d < 0 ) {
646 if( d == min_jlong ) {
647 // (-min_jlong) == min_jlong == (min_jlong / -1)
648 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
649 } else {
650 return TypeLong::make(d, -d, widen);
651 }
652 }
653 return TypeLong::make(-d, d, widen);
654 }
655
656 // Otherwise we give up all hope
657 return TypeLong::LONG;
658 }
659
660
661 //=============================================================================
662 //------------------------------Value------------------------------------------
663 // An DivFNode divides its inputs. The third input is a Control input, used to
664 // prevent hoisting the divide above an unsafe test.
665 const Type *DivFNode::Value( PhaseTransform *phase ) const {
666 // Either input is TOP ==> the result is TOP
667 const Type *t1 = phase->type( in(1) );
668 const Type *t2 = phase->type( in(2) );
669 if( t1 == Type::TOP ) return Type::TOP;
670 if( t2 == Type::TOP ) return Type::TOP;
671
672 // Either input is BOTTOM ==> the result is the local BOTTOM
673 const Type *bot = bottom_type();
674 if( (t1 == bot) || (t2 == bot) ||
675 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
676 return bot;
677
678 // x/x == 1, we ignore 0/0.
679 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
680 // Does not work for variables because of NaN's
681 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
682 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
683 return TypeF::ONE;
684
685 if( t2 == TypeF::ONE )
686 return t1;
687
688 // If divisor is a constant and not zero, divide them numbers
689 if( t1->base() == Type::FloatCon &&
690 t2->base() == Type::FloatCon &&
691 t2->getf() != 0.0 ) // could be negative zero
692 return TypeF::make( t1->getf()/t2->getf() );
693
694 // If the dividend is a constant zero
695 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
696 // Test TypeF::ZERO is not sufficient as it could be negative zero
697
698 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
699 return TypeF::ZERO;
700
701 // Otherwise we give up all hope
702 return Type::FLOAT;
703 }
704
705 //------------------------------isA_Copy---------------------------------------
706 // Dividing by self is 1.
707 // If the divisor is 1, we are an identity on the dividend.
708 Node *DivFNode::Identity( PhaseTransform *phase ) {
709 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
710 }
711
712
713 //------------------------------Idealize---------------------------------------
714 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
715 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
716 // Don't bother trying to transform a dead node
717 if( in(0) && in(0)->is_top() ) return NULL;
718
719 const Type *t2 = phase->type( in(2) );
720 if( t2 == TypeF::ONE ) // Identity?
721 return NULL; // Skip it
722
723 const TypeF *tf = t2->isa_float_constant();
724 if( !tf ) return NULL;
725 if( tf->base() != Type::FloatCon ) return NULL;
726
727 // Check for out of range values
728 if( tf->is_nan() || !tf->is_finite() ) return NULL;
729
730 // Get the value
731 float f = tf->getf();
732 int exp;
733
734 // Only for special case of dividing by a power of 2
735 if( frexp((double)f, &exp) != 0.5 ) return NULL;
736
737 // Limit the range of acceptable exponents
738 if( exp < -126 || exp > 126 ) return NULL;
739
740 // Compute the reciprocal
741 float reciprocal = ((float)1.0) / f;
742
743 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
744
745 // return multiplication by the reciprocal
746 return (new MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
747 }
748
749 //=============================================================================
750 //------------------------------Value------------------------------------------
751 // An DivDNode divides its inputs. The third input is a Control input, used to
752 // prevent hoisting the divide above an unsafe test.
753 const Type *DivDNode::Value( PhaseTransform *phase ) const {
754 // Either input is TOP ==> the result is TOP
755 const Type *t1 = phase->type( in(1) );
756 const Type *t2 = phase->type( in(2) );
757 if( t1 == Type::TOP ) return Type::TOP;
758 if( t2 == Type::TOP ) return Type::TOP;
759
760 // Either input is BOTTOM ==> the result is the local BOTTOM
761 const Type *bot = bottom_type();
762 if( (t1 == bot) || (t2 == bot) ||
763 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
764 return bot;
765
766 // x/x == 1, we ignore 0/0.
767 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
768 // Does not work for variables because of NaN's
769 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
770 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
771 return TypeD::ONE;
772
773 if( t2 == TypeD::ONE )
774 return t1;
775
776 #if defined(IA32)
777 if (!phase->C->method()->is_strict())
778 // Can't trust native compilers to properly fold strict double
779 // division with round-to-zero on this platform.
780 #endif
781 {
782 // If divisor is a constant and not zero, divide them numbers
783 if( t1->base() == Type::DoubleCon &&
784 t2->base() == Type::DoubleCon &&
785 t2->getd() != 0.0 ) // could be negative zero
786 return TypeD::make( t1->getd()/t2->getd() );
787 }
788
789 // If the dividend is a constant zero
790 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
791 // Test TypeF::ZERO is not sufficient as it could be negative zero
792 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
793 return TypeD::ZERO;
794
795 // Otherwise we give up all hope
796 return Type::DOUBLE;
797 }
798
799
800 //------------------------------isA_Copy---------------------------------------
801 // Dividing by self is 1.
802 // If the divisor is 1, we are an identity on the dividend.
803 Node *DivDNode::Identity( PhaseTransform *phase ) {
804 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
805 }
806
807 //------------------------------Idealize---------------------------------------
808 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
809 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
810 // Don't bother trying to transform a dead node
811 if( in(0) && in(0)->is_top() ) return NULL;
812
813 const Type *t2 = phase->type( in(2) );
814 if( t2 == TypeD::ONE ) // Identity?
815 return NULL; // Skip it
816
817 const TypeD *td = t2->isa_double_constant();
818 if( !td ) return NULL;
819 if( td->base() != Type::DoubleCon ) return NULL;
820
821 // Check for out of range values
822 if( td->is_nan() || !td->is_finite() ) return NULL;
823
824 // Get the value
825 double d = td->getd();
826 int exp;
827
828 // Only for special case of dividing by a power of 2
829 if( frexp(d, &exp) != 0.5 ) return NULL;
830
831 // Limit the range of acceptable exponents
832 if( exp < -1021 || exp > 1022 ) return NULL;
833
834 // Compute the reciprocal
835 double reciprocal = 1.0 / d;
836
837 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
838
839 // return multiplication by the reciprocal
840 return (new MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
841 }
842
843 //=============================================================================
844 //------------------------------Idealize---------------------------------------
845 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
846 // Check for dead control input
847 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
848 // Don't bother trying to transform a dead node
849 if( in(0) && in(0)->is_top() ) return NULL;
850
851 // Get the modulus
852 const Type *t = phase->type( in(2) );
853 if( t == Type::TOP ) return NULL;
854 const TypeInt *ti = t->is_int();
855
856 // Check for useless control input
857 // Check for excluding mod-zero case
858 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
859 set_req(0, NULL); // Yank control input
860 return this;
861 }
862
863 // See if we are MOD'ing by 2^k or 2^k-1.
864 if( !ti->is_con() ) return NULL;
865 jint con = ti->get_con();
866
867 Node *hook = new Node(1);
868
869 // First, special check for modulo 2^k-1
870 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
871 uint k = exact_log2(con+1); // Extract k
872
873 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
874 static int unroll_factor[] = { 999, 999, 29, 14, 9, 7, 5, 4, 4, 3, 3, 2, 2, 2, 2, 2, 1 /*past here we assume 1 forever*/};
875 int trip_count = 1;
876 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
877
878 // If the unroll factor is not too large, and if conditional moves are
879 // ok, then use this case
880 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
881 Node *x = in(1); // Value being mod'd
882 Node *divisor = in(2); // Also is mask
883
884 hook->init_req(0, x); // Add a use to x to prevent him from dying
885 // Generate code to reduce X rapidly to nearly 2^k-1.
886 for( int i = 0; i < trip_count; i++ ) {
887 Node *xl = phase->transform( new AndINode(x,divisor) );
888 Node *xh = phase->transform( new RShiftINode(x,phase->intcon(k)) ); // Must be signed
889 x = phase->transform( new AddINode(xh,xl) );
890 hook->set_req(0, x);
891 }
892
893 // Generate sign-fixup code. Was original value positive?
894 // int hack_res = (i >= 0) ? divisor : 1;
895 Node *cmp1 = phase->transform( new CmpINode( in(1), phase->intcon(0) ) );
896 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) );
897 Node *cmov1= phase->transform( new CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
898 // if( x >= hack_res ) x -= divisor;
899 Node *sub = phase->transform( new SubINode( x, divisor ) );
900 Node *cmp2 = phase->transform( new CmpINode( x, cmov1 ) );
901 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) );
902 // Convention is to not transform the return value of an Ideal
903 // since Ideal is expected to return a modified 'this' or a new node.
904 Node *cmov2= new CMoveINode(bol2, x, sub, TypeInt::INT);
905 // cmov2 is now the mod
906
907 // Now remove the bogus extra edges used to keep things alive
908 if (can_reshape) {
909 phase->is_IterGVN()->remove_dead_node(hook);
910 } else {
911 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
912 }
913 return cmov2;
914 }
915 }
916
917 // Fell thru, the unroll case is not appropriate. Transform the modulo
918 // into a long multiply/int multiply/subtract case
919
920 // Cannot handle mod 0, and min_jint isn't handled by the transform
921 if( con == 0 || con == min_jint ) return NULL;
922
923 // Get the absolute value of the constant; at this point, we can use this
924 jint pos_con = (con >= 0) ? con : -con;
925
926 // integer Mod 1 is always 0
927 if( pos_con == 1 ) return new ConINode(TypeInt::ZERO);
928
929 int log2_con = -1;
930
931 // If this is a power of two, they maybe we can mask it
932 if( is_power_of_2(pos_con) ) {
933 log2_con = log2_intptr((intptr_t)pos_con);
934
935 const Type *dt = phase->type(in(1));
936 const TypeInt *dti = dt->isa_int();
937
938 // See if this can be masked, if the dividend is non-negative
939 if( dti && dti->_lo >= 0 )
940 return ( new AndINode( in(1), phase->intcon( pos_con-1 ) ) );
941 }
942
943 // Save in(1) so that it cannot be changed or deleted
944 hook->init_req(0, in(1));
945
946 // Divide using the transform from DivI to MulL
947 Node *result = transform_int_divide( phase, in(1), pos_con );
948 if (result != NULL) {
949 Node *divide = phase->transform(result);
950
951 // Re-multiply, using a shift if this is a power of two
952 Node *mult = NULL;
953
954 if( log2_con >= 0 )
955 mult = phase->transform( new LShiftINode( divide, phase->intcon( log2_con ) ) );
956 else
957 mult = phase->transform( new MulINode( divide, phase->intcon( pos_con ) ) );
958
959 // Finally, subtract the multiplied divided value from the original
960 result = new SubINode( in(1), mult );
961 }
962
963 // Now remove the bogus extra edges used to keep things alive
964 if (can_reshape) {
965 phase->is_IterGVN()->remove_dead_node(hook);
966 } else {
967 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
968 }
969
970 // return the value
971 return result;
972 }
973
974 //------------------------------Value------------------------------------------
975 const Type *ModINode::Value( PhaseTransform *phase ) const {
976 // Either input is TOP ==> the result is TOP
977 const Type *t1 = phase->type( in(1) );
978 const Type *t2 = phase->type( in(2) );
979 if( t1 == Type::TOP ) return Type::TOP;
980 if( t2 == Type::TOP ) return Type::TOP;
981
982 // We always generate the dynamic check for 0.
983 // 0 MOD X is 0
984 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
985 // X MOD X is 0
986 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
987
988 // Either input is BOTTOM ==> the result is the local BOTTOM
989 const Type *bot = bottom_type();
990 if( (t1 == bot) || (t2 == bot) ||
991 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
992 return bot;
993
994 const TypeInt *i1 = t1->is_int();
995 const TypeInt *i2 = t2->is_int();
996 if( !i1->is_con() || !i2->is_con() ) {
997 if( i1->_lo >= 0 && i2->_lo >= 0 )
998 return TypeInt::POS;
999 // If both numbers are not constants, we know little.
1000 return TypeInt::INT;
1001 }
1002 // Mod by zero? Throw exception at runtime!
1003 if( !i2->get_con() ) return TypeInt::POS;
1004
1005 // We must be modulo'ing 2 float constants.
1006 // Check for min_jint % '-1', result is defined to be '0'.
1007 if( i1->get_con() == min_jint && i2->get_con() == -1 )
1008 return TypeInt::ZERO;
1009
1010 return TypeInt::make( i1->get_con() % i2->get_con() );
1011 }
1012
1013
1014 //=============================================================================
1015 //------------------------------Idealize---------------------------------------
1016 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1017 // Check for dead control input
1018 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
1019 // Don't bother trying to transform a dead node
1020 if( in(0) && in(0)->is_top() ) return NULL;
1021
1022 // Get the modulus
1023 const Type *t = phase->type( in(2) );
1024 if( t == Type::TOP ) return NULL;
1025 const TypeLong *tl = t->is_long();
1026
1027 // Check for useless control input
1028 // Check for excluding mod-zero case
1029 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
1030 set_req(0, NULL); // Yank control input
1031 return this;
1032 }
1033
1034 // See if we are MOD'ing by 2^k or 2^k-1.
1035 if( !tl->is_con() ) return NULL;
1036 jlong con = tl->get_con();
1037
1038 Node *hook = new Node(1);
1039
1040 // Expand mod
1041 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
1042 uint k = exact_log2_long(con+1); // Extract k
1043
1044 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
1045 // Used to help a popular random number generator which does a long-mod
1046 // of 2^31-1 and shows up in SpecJBB and SciMark.
1047 static int unroll_factor[] = { 999, 999, 61, 30, 20, 15, 12, 10, 8, 7, 6, 6, 5, 5, 4, 4, 4, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1 /*past here we assume 1 forever*/};
1048 int trip_count = 1;
1049 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
1050
1051 // If the unroll factor is not too large, and if conditional moves are
1052 // ok, then use this case
1053 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
1054 Node *x = in(1); // Value being mod'd
1055 Node *divisor = in(2); // Also is mask
1056
1057 hook->init_req(0, x); // Add a use to x to prevent him from dying
1058 // Generate code to reduce X rapidly to nearly 2^k-1.
1059 for( int i = 0; i < trip_count; i++ ) {
1060 Node *xl = phase->transform( new AndLNode(x,divisor) );
1061 Node *xh = phase->transform( new RShiftLNode(x,phase->intcon(k)) ); // Must be signed
1062 x = phase->transform( new AddLNode(xh,xl) );
1063 hook->set_req(0, x); // Add a use to x to prevent him from dying
1064 }
1065
1066 // Generate sign-fixup code. Was original value positive?
1067 // long hack_res = (i >= 0) ? divisor : CONST64(1);
1068 Node *cmp1 = phase->transform( new CmpLNode( in(1), phase->longcon(0) ) );
1069 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) );
1070 Node *cmov1= phase->transform( new CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
1071 // if( x >= hack_res ) x -= divisor;
1072 Node *sub = phase->transform( new SubLNode( x, divisor ) );
1073 Node *cmp2 = phase->transform( new CmpLNode( x, cmov1 ) );
1074 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) );
1075 // Convention is to not transform the return value of an Ideal
1076 // since Ideal is expected to return a modified 'this' or a new node.
1077 Node *cmov2= new CMoveLNode(bol2, x, sub, TypeLong::LONG);
1078 // cmov2 is now the mod
1079
1080 // Now remove the bogus extra edges used to keep things alive
1081 if (can_reshape) {
1082 phase->is_IterGVN()->remove_dead_node(hook);
1083 } else {
1084 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1085 }
1086 return cmov2;
1087 }
1088 }
1089
1090 // Fell thru, the unroll case is not appropriate. Transform the modulo
1091 // into a long multiply/int multiply/subtract case
1092
1093 // Cannot handle mod 0, and min_jlong isn't handled by the transform
1094 if( con == 0 || con == min_jlong ) return NULL;
1095
1096 // Get the absolute value of the constant; at this point, we can use this
1097 jlong pos_con = (con >= 0) ? con : -con;
1098
1099 // integer Mod 1 is always 0
1100 if( pos_con == 1 ) return new ConLNode(TypeLong::ZERO);
1101
1102 int log2_con = -1;
1103
1104 // If this is a power of two, then maybe we can mask it
1105 if( is_power_of_2_long(pos_con) ) {
1106 log2_con = exact_log2_long(pos_con);
1107
1108 const Type *dt = phase->type(in(1));
1109 const TypeLong *dtl = dt->isa_long();
1110
1111 // See if this can be masked, if the dividend is non-negative
1112 if( dtl && dtl->_lo >= 0 )
1113 return ( new AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1114 }
1115
1116 // Save in(1) so that it cannot be changed or deleted
1117 hook->init_req(0, in(1));
1118
1119 // Divide using the transform from DivL to MulL
1120 Node *result = transform_long_divide( phase, in(1), pos_con );
1121 if (result != NULL) {
1122 Node *divide = phase->transform(result);
1123
1124 // Re-multiply, using a shift if this is a power of two
1125 Node *mult = NULL;
1126
1127 if( log2_con >= 0 )
1128 mult = phase->transform( new LShiftLNode( divide, phase->intcon( log2_con ) ) );
1129 else
1130 mult = phase->transform( new MulLNode( divide, phase->longcon( pos_con ) ) );
1131
1132 // Finally, subtract the multiplied divided value from the original
1133 result = new SubLNode( in(1), mult );
1134 }
1135
1136 // Now remove the bogus extra edges used to keep things alive
1137 if (can_reshape) {
1138 phase->is_IterGVN()->remove_dead_node(hook);
1139 } else {
1140 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1141 }
1142
1143 // return the value
1144 return result;
1145 }
1146
1147 //------------------------------Value------------------------------------------
1148 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1149 // Either input is TOP ==> the result is TOP
1150 const Type *t1 = phase->type( in(1) );
1151 const Type *t2 = phase->type( in(2) );
1152 if( t1 == Type::TOP ) return Type::TOP;
1153 if( t2 == Type::TOP ) return Type::TOP;
1154
1155 // We always generate the dynamic check for 0.
1156 // 0 MOD X is 0
1157 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1158 // X MOD X is 0
1159 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1160
1161 // Either input is BOTTOM ==> the result is the local BOTTOM
1162 const Type *bot = bottom_type();
1163 if( (t1 == bot) || (t2 == bot) ||
1164 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1165 return bot;
1166
1167 const TypeLong *i1 = t1->is_long();
1168 const TypeLong *i2 = t2->is_long();
1169 if( !i1->is_con() || !i2->is_con() ) {
1170 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1171 return TypeLong::POS;
1172 // If both numbers are not constants, we know little.
1173 return TypeLong::LONG;
1174 }
1175 // Mod by zero? Throw exception at runtime!
1176 if( !i2->get_con() ) return TypeLong::POS;
1177
1178 // We must be modulo'ing 2 float constants.
1179 // Check for min_jint % '-1', result is defined to be '0'.
1180 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1181 return TypeLong::ZERO;
1182
1183 return TypeLong::make( i1->get_con() % i2->get_con() );
1184 }
1185
1186
1187 //=============================================================================
1188 //------------------------------Value------------------------------------------
1189 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1190 // Either input is TOP ==> the result is TOP
1191 const Type *t1 = phase->type( in(1) );
1192 const Type *t2 = phase->type( in(2) );
1193 if( t1 == Type::TOP ) return Type::TOP;
1194 if( t2 == Type::TOP ) return Type::TOP;
1195
1196 // Either input is BOTTOM ==> the result is the local BOTTOM
1197 const Type *bot = bottom_type();
1198 if( (t1 == bot) || (t2 == bot) ||
1199 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1200 return bot;
1201
1202 // If either number is not a constant, we know nothing.
1203 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1204 return Type::FLOAT; // note: x%x can be either NaN or 0
1205 }
1206
1207 float f1 = t1->getf();
1208 float f2 = t2->getf();
1209 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1210 jint x2 = jint_cast(f2);
1211
1212 // If either is a NaN, return an input NaN
1213 if (g_isnan(f1)) return t1;
1214 if (g_isnan(f2)) return t2;
1215
1216 // If an operand is infinity or the divisor is +/- zero, punt.
1217 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1218 return Type::FLOAT;
1219
1220 // We must be modulo'ing 2 float constants.
1221 // Make sure that the sign of the fmod is equal to the sign of the dividend
1222 jint xr = jint_cast(fmod(f1, f2));
1223 if ((x1 ^ xr) < 0) {
1224 xr ^= min_jint;
1225 }
1226
1227 return TypeF::make(jfloat_cast(xr));
1228 }
1229
1230
1231 //=============================================================================
1232 //------------------------------Value------------------------------------------
1233 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1234 // Either input is TOP ==> the result is TOP
1235 const Type *t1 = phase->type( in(1) );
1236 const Type *t2 = phase->type( in(2) );
1237 if( t1 == Type::TOP ) return Type::TOP;
1238 if( t2 == Type::TOP ) return Type::TOP;
1239
1240 // Either input is BOTTOM ==> the result is the local BOTTOM
1241 const Type *bot = bottom_type();
1242 if( (t1 == bot) || (t2 == bot) ||
1243 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1244 return bot;
1245
1246 // If either number is not a constant, we know nothing.
1247 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1248 return Type::DOUBLE; // note: x%x can be either NaN or 0
1249 }
1250
1251 double f1 = t1->getd();
1252 double f2 = t2->getd();
1253 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1254 jlong x2 = jlong_cast(f2);
1255
1256 // If either is a NaN, return an input NaN
1257 if (g_isnan(f1)) return t1;
1258 if (g_isnan(f2)) return t2;
1259
1260 // If an operand is infinity or the divisor is +/- zero, punt.
1261 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1262 return Type::DOUBLE;
1263
1264 // We must be modulo'ing 2 double constants.
1265 // Make sure that the sign of the fmod is equal to the sign of the dividend
1266 jlong xr = jlong_cast(fmod(f1, f2));
1267 if ((x1 ^ xr) < 0) {
1268 xr ^= min_jlong;
1269 }
1270
1271 return TypeD::make(jdouble_cast(xr));
1272 }
1273
1274 //=============================================================================
1275
1276 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1277 init_req(0, c);
1278 init_req(1, dividend);
1279 init_req(2, divisor);
1280 }
1281
1282 //------------------------------make------------------------------------------
1283 DivModINode* DivModINode::make(Node* div_or_mod) {
1284 Node* n = div_or_mod;
1285 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1286 "only div or mod input pattern accepted");
1287
1288 DivModINode* divmod = new DivModINode(n->in(0), n->in(1), n->in(2));
1289 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num);
1290 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num);
1291 return divmod;
1292 }
1293
1294 //------------------------------make------------------------------------------
1295 DivModLNode* DivModLNode::make(Node* div_or_mod) {
1296 Node* n = div_or_mod;
1297 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1298 "only div or mod input pattern accepted");
1299
1300 DivModLNode* divmod = new DivModLNode(n->in(0), n->in(1), n->in(2));
1301 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num);
1302 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num);
1303 return divmod;
1304 }
1305
1306 //------------------------------match------------------------------------------
1307 // return result(s) along with their RegMask info
1308 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1309 uint ideal_reg = proj->ideal_reg();
1310 RegMask rm;
1311 if (proj->_con == div_proj_num) {
1312 rm = match->divI_proj_mask();
1313 } else {
1314 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1315 rm = match->modI_proj_mask();
1316 }
1317 return new MachProjNode(this, proj->_con, rm, ideal_reg);
1318 }
1319
1320
1321 //------------------------------match------------------------------------------
1322 // return result(s) along with their RegMask info
1323 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1324 uint ideal_reg = proj->ideal_reg();
1325 RegMask rm;
1326 if (proj->_con == div_proj_num) {
1327 rm = match->divL_proj_mask();
1328 } else {
1329 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1330 rm = match->modL_proj_mask();
1331 }
1332 return new MachProjNode(this, proj->_con, rm, ideal_reg);
1333 }