1 /*
2 * Copyright (c) 1997, 2012, 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,
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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 = 0x8000000000000000LL; // 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 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
483
484 // Dividing by MININT does not optimize as a power-of-2 shift.
485 if( i == min_jint ) return NULL;
486
487 return transform_int_divide( phase, in(1), i );
488 }
489
490 //------------------------------Value------------------------------------------
491 // A DivINode divides its inputs. The third input is a Control input, used to
492 // prevent hoisting the divide above an unsafe test.
493 const Type *DivINode::Value( PhaseTransform *phase ) const {
494 // Either input is TOP ==> the result is TOP
495 const Type *t1 = phase->type( in(1) );
496 const Type *t2 = phase->type( in(2) );
497 if( t1 == Type::TOP ) return Type::TOP;
498 if( t2 == Type::TOP ) return Type::TOP;
499
500 // x/x == 1 since we always generate the dynamic divisor check for 0.
501 if( phase->eqv( in(1), in(2) ) )
502 return TypeInt::ONE;
503
504 // Either input is BOTTOM ==> the result is the local BOTTOM
505 const Type *bot = bottom_type();
506 if( (t1 == bot) || (t2 == bot) ||
507 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
508 return bot;
509
510 // Divide the two numbers. We approximate.
511 // If divisor is a constant and not zero
512 const TypeInt *i1 = t1->is_int();
513 const TypeInt *i2 = t2->is_int();
514 int widen = MAX2(i1->_widen, i2->_widen);
515
516 if( i2->is_con() && i2->get_con() != 0 ) {
517 int32 d = i2->get_con(); // Divisor
518 jint lo, hi;
519 if( d >= 0 ) {
520 lo = i1->_lo/d;
521 hi = i1->_hi/d;
522 } else {
523 if( d == -1 && i1->_lo == min_jint ) {
524 // 'min_jint/-1' throws arithmetic exception during compilation
525 lo = min_jint;
526 // do not support holes, 'hi' must go to either min_jint or max_jint:
527 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
528 hi = i1->_hi == min_jint ? min_jint : max_jint;
529 } else {
530 lo = i1->_hi/d;
531 hi = i1->_lo/d;
532 }
533 }
534 return TypeInt::make(lo, hi, widen);
535 }
536
537 // If the dividend is a constant
538 if( i1->is_con() ) {
539 int32 d = i1->get_con();
540 if( d < 0 ) {
541 if( d == min_jint ) {
542 // (-min_jint) == min_jint == (min_jint / -1)
543 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
544 } else {
545 return TypeInt::make(d, -d, widen);
546 }
547 }
548 return TypeInt::make(-d, d, widen);
549 }
550
551 // Otherwise we give up all hope
552 return TypeInt::INT;
553 }
554
555
556 //=============================================================================
557 //------------------------------Identity---------------------------------------
558 // If the divisor is 1, we are an identity on the dividend.
559 Node *DivLNode::Identity( PhaseTransform *phase ) {
560 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
561 }
562
563 //------------------------------Idealize---------------------------------------
564 // Dividing by a power of 2 is a shift.
565 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
566 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
567 // Don't bother trying to transform a dead node
568 if( in(0) && in(0)->is_top() ) return NULL;
569
570 const Type *t = phase->type( in(2) );
571 if( t == TypeLong::ONE ) // Identity?
572 return NULL; // Skip it
573
574 const TypeLong *tl = t->isa_long();
575 if( !tl ) return NULL;
576 if( !tl->is_con() ) return NULL;
577 jlong l = tl->get_con(); // Get divisor
578
579 if (l == 0) return NULL; // Dividing by zero constant does not idealize
580
581 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
582
583 // Dividing by MINLONG does not optimize as a power-of-2 shift.
584 if( l == min_jlong ) return NULL;
585
586 return transform_long_divide( phase, in(1), l );
587 }
588
589 //------------------------------Value------------------------------------------
590 // A DivLNode divides its inputs. The third input is a Control input, used to
591 // prevent hoisting the divide above an unsafe test.
592 const Type *DivLNode::Value( PhaseTransform *phase ) const {
593 // Either input is TOP ==> the result is TOP
594 const Type *t1 = phase->type( in(1) );
595 const Type *t2 = phase->type( in(2) );
596 if( t1 == Type::TOP ) return Type::TOP;
597 if( t2 == Type::TOP ) return Type::TOP;
598
599 // x/x == 1 since we always generate the dynamic divisor check for 0.
600 if( phase->eqv( in(1), in(2) ) )
601 return TypeLong::ONE;
602
603 // Either input is BOTTOM ==> the result is the local BOTTOM
604 const Type *bot = bottom_type();
605 if( (t1 == bot) || (t2 == bot) ||
606 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
607 return bot;
608
609 // Divide the two numbers. We approximate.
610 // If divisor is a constant and not zero
611 const TypeLong *i1 = t1->is_long();
612 const TypeLong *i2 = t2->is_long();
613 int widen = MAX2(i1->_widen, i2->_widen);
614
615 if( i2->is_con() && i2->get_con() != 0 ) {
616 jlong d = i2->get_con(); // Divisor
617 jlong lo, hi;
618 if( d >= 0 ) {
619 lo = i1->_lo/d;
620 hi = i1->_hi/d;
621 } else {
622 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
623 // 'min_jlong/-1' throws arithmetic exception during compilation
624 lo = min_jlong;
625 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
626 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
627 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
628 } else {
629 lo = i1->_hi/d;
630 hi = i1->_lo/d;
631 }
632 }
633 return TypeLong::make(lo, hi, widen);
634 }
635
636 // If the dividend is a constant
637 if( i1->is_con() ) {
638 jlong d = i1->get_con();
639 if( d < 0 ) {
640 if( d == min_jlong ) {
641 // (-min_jlong) == min_jlong == (min_jlong / -1)
642 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
643 } else {
644 return TypeLong::make(d, -d, widen);
645 }
646 }
647 return TypeLong::make(-d, d, widen);
648 }
649
650 // Otherwise we give up all hope
651 return TypeLong::LONG;
652 }
653
654
655 //=============================================================================
656 //------------------------------Value------------------------------------------
657 // An DivFNode divides its inputs. The third input is a Control input, used to
658 // prevent hoisting the divide above an unsafe test.
659 const Type *DivFNode::Value( PhaseTransform *phase ) const {
660 // Either input is TOP ==> the result is TOP
661 const Type *t1 = phase->type( in(1) );
662 const Type *t2 = phase->type( in(2) );
663 if( t1 == Type::TOP ) return Type::TOP;
664 if( t2 == Type::TOP ) return Type::TOP;
665
666 // Either input is BOTTOM ==> the result is the local BOTTOM
667 const Type *bot = bottom_type();
668 if( (t1 == bot) || (t2 == bot) ||
669 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
670 return bot;
671
672 // x/x == 1, we ignore 0/0.
673 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
674 // Does not work for variables because of NaN's
675 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
676 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
677 return TypeF::ONE;
678
679 if( t2 == TypeF::ONE )
680 return t1;
681
682 // If divisor is a constant and not zero, divide them numbers
683 if( t1->base() == Type::FloatCon &&
684 t2->base() == Type::FloatCon &&
685 t2->getf() != 0.0 ) // could be negative zero
686 return TypeF::make( t1->getf()/t2->getf() );
687
688 // If the dividend is a constant zero
689 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
690 // Test TypeF::ZERO is not sufficient as it could be negative zero
691
692 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
693 return TypeF::ZERO;
694
695 // Otherwise we give up all hope
696 return Type::FLOAT;
697 }
698
699 //------------------------------isA_Copy---------------------------------------
700 // Dividing by self is 1.
701 // If the divisor is 1, we are an identity on the dividend.
702 Node *DivFNode::Identity( PhaseTransform *phase ) {
703 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
704 }
705
706
707 //------------------------------Idealize---------------------------------------
708 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
709 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
710 // Don't bother trying to transform a dead node
711 if( in(0) && in(0)->is_top() ) return NULL;
712
713 const Type *t2 = phase->type( in(2) );
714 if( t2 == TypeF::ONE ) // Identity?
715 return NULL; // Skip it
716
717 const TypeF *tf = t2->isa_float_constant();
718 if( !tf ) return NULL;
719 if( tf->base() != Type::FloatCon ) return NULL;
720
721 // Check for out of range values
722 if( tf->is_nan() || !tf->is_finite() ) return NULL;
723
724 // Get the value
725 float f = tf->getf();
726 int exp;
727
728 // Only for special case of dividing by a power of 2
729 if( frexp((double)f, &exp) != 0.5 ) return NULL;
730
731 // Limit the range of acceptable exponents
732 if( exp < -126 || exp > 126 ) return NULL;
733
734 // Compute the reciprocal
735 float reciprocal = ((float)1.0) / f;
736
737 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
738
739 // return multiplication by the reciprocal
740 return (new MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
741 }
742
743 //=============================================================================
744 //------------------------------Value------------------------------------------
745 // An DivDNode divides its inputs. The third input is a Control input, used to
746 // prevent hoisting the divide above an unsafe test.
747 const Type *DivDNode::Value( PhaseTransform *phase ) const {
748 // Either input is TOP ==> the result is TOP
749 const Type *t1 = phase->type( in(1) );
750 const Type *t2 = phase->type( in(2) );
751 if( t1 == Type::TOP ) return Type::TOP;
752 if( t2 == Type::TOP ) return Type::TOP;
753
754 // Either input is BOTTOM ==> the result is the local BOTTOM
755 const Type *bot = bottom_type();
756 if( (t1 == bot) || (t2 == bot) ||
757 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
758 return bot;
759
760 // x/x == 1, we ignore 0/0.
761 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
762 // Does not work for variables because of NaN's
763 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
764 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
765 return TypeD::ONE;
766
767 if( t2 == TypeD::ONE )
768 return t1;
769
770 #if defined(IA32)
771 if (!phase->C->method()->is_strict())
772 // Can't trust native compilers to properly fold strict double
773 // division with round-to-zero on this platform.
774 #endif
775 {
776 // If divisor is a constant and not zero, divide them numbers
777 if( t1->base() == Type::DoubleCon &&
778 t2->base() == Type::DoubleCon &&
779 t2->getd() != 0.0 ) // could be negative zero
780 return TypeD::make( t1->getd()/t2->getd() );
781 }
782
783 // If the dividend is a constant zero
784 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
785 // Test TypeF::ZERO is not sufficient as it could be negative zero
786 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
787 return TypeD::ZERO;
788
789 // Otherwise we give up all hope
790 return Type::DOUBLE;
791 }
792
793
794 //------------------------------isA_Copy---------------------------------------
795 // Dividing by self is 1.
796 // If the divisor is 1, we are an identity on the dividend.
797 Node *DivDNode::Identity( PhaseTransform *phase ) {
798 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
799 }
800
801 //------------------------------Idealize---------------------------------------
802 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
803 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
804 // Don't bother trying to transform a dead node
805 if( in(0) && in(0)->is_top() ) return NULL;
806
807 const Type *t2 = phase->type( in(2) );
808 if( t2 == TypeD::ONE ) // Identity?
809 return NULL; // Skip it
810
811 const TypeD *td = t2->isa_double_constant();
812 if( !td ) return NULL;
813 if( td->base() != Type::DoubleCon ) return NULL;
814
815 // Check for out of range values
816 if( td->is_nan() || !td->is_finite() ) return NULL;
817
818 // Get the value
819 double d = td->getd();
820 int exp;
821
822 // Only for special case of dividing by a power of 2
823 if( frexp(d, &exp) != 0.5 ) return NULL;
824
825 // Limit the range of acceptable exponents
826 if( exp < -1021 || exp > 1022 ) return NULL;
827
828 // Compute the reciprocal
829 double reciprocal = 1.0 / d;
830
831 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
832
833 // return multiplication by the reciprocal
834 return (new MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
835 }
836
837 //=============================================================================
838 //------------------------------Idealize---------------------------------------
839 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
840 // Check for dead control input
841 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
842 // Don't bother trying to transform a dead node
843 if( in(0) && in(0)->is_top() ) return NULL;
844
845 // Get the modulus
846 const Type *t = phase->type( in(2) );
847 if( t == Type::TOP ) return NULL;
848 const TypeInt *ti = t->is_int();
849
850 // Check for useless control input
851 // Check for excluding mod-zero case
852 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
853 set_req(0, NULL); // Yank control input
854 return this;
855 }
856
857 // See if we are MOD'ing by 2^k or 2^k-1.
858 if( !ti->is_con() ) return NULL;
859 jint con = ti->get_con();
860
861 Node *hook = new Node(1);
862
863 // First, special check for modulo 2^k-1
864 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
865 uint k = exact_log2(con+1); // Extract k
866
867 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
868 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*/};
869 int trip_count = 1;
870 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
871
872 // If the unroll factor is not too large, and if conditional moves are
873 // ok, then use this case
874 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
875 Node *x = in(1); // Value being mod'd
876 Node *divisor = in(2); // Also is mask
877
878 hook->init_req(0, x); // Add a use to x to prevent him from dying
879 // Generate code to reduce X rapidly to nearly 2^k-1.
880 for( int i = 0; i < trip_count; i++ ) {
881 Node *xl = phase->transform( new AndINode(x,divisor) );
882 Node *xh = phase->transform( new RShiftINode(x,phase->intcon(k)) ); // Must be signed
883 x = phase->transform( new AddINode(xh,xl) );
884 hook->set_req(0, x);
885 }
886
887 // Generate sign-fixup code. Was original value positive?
888 // int hack_res = (i >= 0) ? divisor : 1;
889 Node *cmp1 = phase->transform( new CmpINode( in(1), phase->intcon(0) ) );
890 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) );
891 Node *cmov1= phase->transform( new CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
892 // if( x >= hack_res ) x -= divisor;
893 Node *sub = phase->transform( new SubINode( x, divisor ) );
894 Node *cmp2 = phase->transform( new CmpINode( x, cmov1 ) );
895 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) );
896 // Convention is to not transform the return value of an Ideal
897 // since Ideal is expected to return a modified 'this' or a new node.
898 Node *cmov2= new CMoveINode(bol2, x, sub, TypeInt::INT);
899 // cmov2 is now the mod
900
901 // Now remove the bogus extra edges used to keep things alive
902 if (can_reshape) {
903 phase->is_IterGVN()->remove_dead_node(hook);
904 } else {
905 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
906 }
907 return cmov2;
908 }
909 }
910
911 // Fell thru, the unroll case is not appropriate. Transform the modulo
912 // into a long multiply/int multiply/subtract case
913
914 // Cannot handle mod 0, and min_jint isn't handled by the transform
915 if( con == 0 || con == min_jint ) return NULL;
916
917 // Get the absolute value of the constant; at this point, we can use this
918 jint pos_con = (con >= 0) ? con : -con;
919
920 // integer Mod 1 is always 0
921 if( pos_con == 1 ) return new ConINode(TypeInt::ZERO);
922
923 int log2_con = -1;
924
925 // If this is a power of two, they maybe we can mask it
926 if( is_power_of_2(pos_con) ) {
927 log2_con = log2_intptr((intptr_t)pos_con);
928
929 const Type *dt = phase->type(in(1));
930 const TypeInt *dti = dt->isa_int();
931
932 // See if this can be masked, if the dividend is non-negative
933 if( dti && dti->_lo >= 0 )
934 return ( new AndINode( in(1), phase->intcon( pos_con-1 ) ) );
935 }
936
937 // Save in(1) so that it cannot be changed or deleted
938 hook->init_req(0, in(1));
939
940 // Divide using the transform from DivI to MulL
941 Node *result = transform_int_divide( phase, in(1), pos_con );
942 if (result != NULL) {
943 Node *divide = phase->transform(result);
944
945 // Re-multiply, using a shift if this is a power of two
946 Node *mult = NULL;
947
948 if( log2_con >= 0 )
949 mult = phase->transform( new LShiftINode( divide, phase->intcon( log2_con ) ) );
950 else
951 mult = phase->transform( new MulINode( divide, phase->intcon( pos_con ) ) );
952
953 // Finally, subtract the multiplied divided value from the original
954 result = new SubINode( in(1), mult );
955 }
956
957 // Now remove the bogus extra edges used to keep things alive
958 if (can_reshape) {
959 phase->is_IterGVN()->remove_dead_node(hook);
960 } else {
961 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
962 }
963
964 // return the value
965 return result;
966 }
967
968 //------------------------------Value------------------------------------------
969 const Type *ModINode::Value( PhaseTransform *phase ) const {
970 // Either input is TOP ==> the result is TOP
971 const Type *t1 = phase->type( in(1) );
972 const Type *t2 = phase->type( in(2) );
973 if( t1 == Type::TOP ) return Type::TOP;
974 if( t2 == Type::TOP ) return Type::TOP;
975
976 // We always generate the dynamic check for 0.
977 // 0 MOD X is 0
978 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
979 // X MOD X is 0
980 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
981
982 // Either input is BOTTOM ==> the result is the local BOTTOM
983 const Type *bot = bottom_type();
984 if( (t1 == bot) || (t2 == bot) ||
985 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
986 return bot;
987
988 const TypeInt *i1 = t1->is_int();
989 const TypeInt *i2 = t2->is_int();
990 if( !i1->is_con() || !i2->is_con() ) {
991 if( i1->_lo >= 0 && i2->_lo >= 0 )
992 return TypeInt::POS;
993 // If both numbers are not constants, we know little.
994 return TypeInt::INT;
995 }
996 // Mod by zero? Throw exception at runtime!
997 if( !i2->get_con() ) return TypeInt::POS;
998
999 // We must be modulo'ing 2 float constants.
1000 // Check for min_jint % '-1', result is defined to be '0'.
1001 if( i1->get_con() == min_jint && i2->get_con() == -1 )
1002 return TypeInt::ZERO;
1003
1004 return TypeInt::make( i1->get_con() % i2->get_con() );
1005 }
1006
1007
1008 //=============================================================================
1009 //------------------------------Idealize---------------------------------------
1010 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1011 // Check for dead control input
1012 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
1013 // Don't bother trying to transform a dead node
1014 if( in(0) && in(0)->is_top() ) return NULL;
1015
1016 // Get the modulus
1017 const Type *t = phase->type( in(2) );
1018 if( t == Type::TOP ) return NULL;
1019 const TypeLong *tl = t->is_long();
1020
1021 // Check for useless control input
1022 // Check for excluding mod-zero case
1023 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
1024 set_req(0, NULL); // Yank control input
1025 return this;
1026 }
1027
1028 // See if we are MOD'ing by 2^k or 2^k-1.
1029 if( !tl->is_con() ) return NULL;
1030 jlong con = tl->get_con();
1031
1032 Node *hook = new Node(1);
1033
1034 // Expand mod
1035 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
1036 uint k = exact_log2_long(con+1); // Extract k
1037
1038 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
1039 // Used to help a popular random number generator which does a long-mod
1040 // of 2^31-1 and shows up in SpecJBB and SciMark.
1041 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*/};
1042 int trip_count = 1;
1043 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
1044
1045 // If the unroll factor is not too large, and if conditional moves are
1046 // ok, then use this case
1047 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
1048 Node *x = in(1); // Value being mod'd
1049 Node *divisor = in(2); // Also is mask
1050
1051 hook->init_req(0, x); // Add a use to x to prevent him from dying
1052 // Generate code to reduce X rapidly to nearly 2^k-1.
1053 for( int i = 0; i < trip_count; i++ ) {
1054 Node *xl = phase->transform( new AndLNode(x,divisor) );
1055 Node *xh = phase->transform( new RShiftLNode(x,phase->intcon(k)) ); // Must be signed
1056 x = phase->transform( new AddLNode(xh,xl) );
1057 hook->set_req(0, x); // Add a use to x to prevent him from dying
1058 }
1059
1060 // Generate sign-fixup code. Was original value positive?
1061 // long hack_res = (i >= 0) ? divisor : CONST64(1);
1062 Node *cmp1 = phase->transform( new CmpLNode( in(1), phase->longcon(0) ) );
1063 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) );
1064 Node *cmov1= phase->transform( new CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
1065 // if( x >= hack_res ) x -= divisor;
1066 Node *sub = phase->transform( new SubLNode( x, divisor ) );
1067 Node *cmp2 = phase->transform( new CmpLNode( x, cmov1 ) );
1068 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) );
1069 // Convention is to not transform the return value of an Ideal
1070 // since Ideal is expected to return a modified 'this' or a new node.
1071 Node *cmov2= new CMoveLNode(bol2, x, sub, TypeLong::LONG);
1072 // cmov2 is now the mod
1073
1074 // Now remove the bogus extra edges used to keep things alive
1075 if (can_reshape) {
1076 phase->is_IterGVN()->remove_dead_node(hook);
1077 } else {
1078 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1079 }
1080 return cmov2;
1081 }
1082 }
1083
1084 // Fell thru, the unroll case is not appropriate. Transform the modulo
1085 // into a long multiply/int multiply/subtract case
1086
1087 // Cannot handle mod 0, and min_jlong isn't handled by the transform
1088 if( con == 0 || con == min_jlong ) return NULL;
1089
1090 // Get the absolute value of the constant; at this point, we can use this
1091 jlong pos_con = (con >= 0) ? con : -con;
1092
1093 // integer Mod 1 is always 0
1094 if( pos_con == 1 ) return new ConLNode(TypeLong::ZERO);
1095
1096 int log2_con = -1;
1097
1098 // If this is a power of two, then maybe we can mask it
1099 if( is_power_of_2_long(pos_con) ) {
1100 log2_con = exact_log2_long(pos_con);
1101
1102 const Type *dt = phase->type(in(1));
1103 const TypeLong *dtl = dt->isa_long();
1104
1105 // See if this can be masked, if the dividend is non-negative
1106 if( dtl && dtl->_lo >= 0 )
1107 return ( new AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1108 }
1109
1110 // Save in(1) so that it cannot be changed or deleted
1111 hook->init_req(0, in(1));
1112
1113 // Divide using the transform from DivL to MulL
1114 Node *result = transform_long_divide( phase, in(1), pos_con );
1115 if (result != NULL) {
1116 Node *divide = phase->transform(result);
1117
1118 // Re-multiply, using a shift if this is a power of two
1119 Node *mult = NULL;
1120
1121 if( log2_con >= 0 )
1122 mult = phase->transform( new LShiftLNode( divide, phase->intcon( log2_con ) ) );
1123 else
1124 mult = phase->transform( new MulLNode( divide, phase->longcon( pos_con ) ) );
1125
1126 // Finally, subtract the multiplied divided value from the original
1127 result = new SubLNode( in(1), mult );
1128 }
1129
1130 // Now remove the bogus extra edges used to keep things alive
1131 if (can_reshape) {
1132 phase->is_IterGVN()->remove_dead_node(hook);
1133 } else {
1134 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1135 }
1136
1137 // return the value
1138 return result;
1139 }
1140
1141 //------------------------------Value------------------------------------------
1142 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1143 // Either input is TOP ==> the result is TOP
1144 const Type *t1 = phase->type( in(1) );
1145 const Type *t2 = phase->type( in(2) );
1146 if( t1 == Type::TOP ) return Type::TOP;
1147 if( t2 == Type::TOP ) return Type::TOP;
1148
1149 // We always generate the dynamic check for 0.
1150 // 0 MOD X is 0
1151 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1152 // X MOD X is 0
1153 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1154
1155 // Either input is BOTTOM ==> the result is the local BOTTOM
1156 const Type *bot = bottom_type();
1157 if( (t1 == bot) || (t2 == bot) ||
1158 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1159 return bot;
1160
1161 const TypeLong *i1 = t1->is_long();
1162 const TypeLong *i2 = t2->is_long();
1163 if( !i1->is_con() || !i2->is_con() ) {
1164 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1165 return TypeLong::POS;
1166 // If both numbers are not constants, we know little.
1167 return TypeLong::LONG;
1168 }
1169 // Mod by zero? Throw exception at runtime!
1170 if( !i2->get_con() ) return TypeLong::POS;
1171
1172 // We must be modulo'ing 2 float constants.
1173 // Check for min_jint % '-1', result is defined to be '0'.
1174 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1175 return TypeLong::ZERO;
1176
1177 return TypeLong::make( i1->get_con() % i2->get_con() );
1178 }
1179
1180
1181 //=============================================================================
1182 //------------------------------Value------------------------------------------
1183 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1184 // Either input is TOP ==> the result is TOP
1185 const Type *t1 = phase->type( in(1) );
1186 const Type *t2 = phase->type( in(2) );
1187 if( t1 == Type::TOP ) return Type::TOP;
1188 if( t2 == Type::TOP ) return Type::TOP;
1189
1190 // Either input is BOTTOM ==> the result is the local BOTTOM
1191 const Type *bot = bottom_type();
1192 if( (t1 == bot) || (t2 == bot) ||
1193 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1194 return bot;
1195
1196 // If either number is not a constant, we know nothing.
1197 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1198 return Type::FLOAT; // note: x%x can be either NaN or 0
1199 }
1200
1201 float f1 = t1->getf();
1202 float f2 = t2->getf();
1203 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1204 jint x2 = jint_cast(f2);
1205
1206 // If either is a NaN, return an input NaN
1207 if (g_isnan(f1)) return t1;
1208 if (g_isnan(f2)) return t2;
1209
1210 // If an operand is infinity or the divisor is +/- zero, punt.
1211 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1212 return Type::FLOAT;
1213
1214 // We must be modulo'ing 2 float constants.
1215 // Make sure that the sign of the fmod is equal to the sign of the dividend
1216 jint xr = jint_cast(fmod(f1, f2));
1217 if ((x1 ^ xr) < 0) {
1218 xr ^= min_jint;
1219 }
1220
1221 return TypeF::make(jfloat_cast(xr));
1222 }
1223
1224
1225 //=============================================================================
1226 //------------------------------Value------------------------------------------
1227 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1228 // Either input is TOP ==> the result is TOP
1229 const Type *t1 = phase->type( in(1) );
1230 const Type *t2 = phase->type( in(2) );
1231 if( t1 == Type::TOP ) return Type::TOP;
1232 if( t2 == Type::TOP ) return Type::TOP;
1233
1234 // Either input is BOTTOM ==> the result is the local BOTTOM
1235 const Type *bot = bottom_type();
1236 if( (t1 == bot) || (t2 == bot) ||
1237 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1238 return bot;
1239
1240 // If either number is not a constant, we know nothing.
1241 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1242 return Type::DOUBLE; // note: x%x can be either NaN or 0
1243 }
1244
1245 double f1 = t1->getd();
1246 double f2 = t2->getd();
1247 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1248 jlong x2 = jlong_cast(f2);
1249
1250 // If either is a NaN, return an input NaN
1251 if (g_isnan(f1)) return t1;
1252 if (g_isnan(f2)) return t2;
1253
1254 // If an operand is infinity or the divisor is +/- zero, punt.
1255 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1256 return Type::DOUBLE;
1257
1258 // We must be modulo'ing 2 double constants.
1259 // Make sure that the sign of the fmod is equal to the sign of the dividend
1260 jlong xr = jlong_cast(fmod(f1, f2));
1261 if ((x1 ^ xr) < 0) {
1262 xr ^= min_jlong;
1263 }
1264
1265 return TypeD::make(jdouble_cast(xr));
1266 }
1267
1268 //=============================================================================
1269
1270 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1271 init_req(0, c);
1272 init_req(1, dividend);
1273 init_req(2, divisor);
1274 }
1275
1276 //------------------------------make------------------------------------------
1277 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
1278 Node* n = div_or_mod;
1279 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1280 "only div or mod input pattern accepted");
1281
1282 DivModINode* divmod = new DivModINode(n->in(0), n->in(1), n->in(2));
1283 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num);
1284 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num);
1285 return divmod;
1286 }
1287
1288 //------------------------------make------------------------------------------
1289 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
1290 Node* n = div_or_mod;
1291 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1292 "only div or mod input pattern accepted");
1293
1294 DivModLNode* divmod = new DivModLNode(n->in(0), n->in(1), n->in(2));
1295 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num);
1296 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num);
1297 return divmod;
1298 }
1299
1300 //------------------------------match------------------------------------------
1301 // return result(s) along with their RegMask info
1302 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1303 uint ideal_reg = proj->ideal_reg();
1304 RegMask rm;
1305 if (proj->_con == div_proj_num) {
1306 rm = match->divI_proj_mask();
1307 } else {
1308 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1309 rm = match->modI_proj_mask();
1310 }
1311 return new MachProjNode(this, proj->_con, rm, ideal_reg);
1312 }
1313
1314
1315 //------------------------------match------------------------------------------
1316 // return result(s) along with their RegMask info
1317 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1318 uint ideal_reg = proj->ideal_reg();
1319 RegMask rm;
1320 if (proj->_con == div_proj_num) {
1321 rm = match->divL_proj_mask();
1322 } else {
1323 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1324 rm = match->modL_proj_mask();
1325 }
1326 return new MachProjNode(this, proj->_con, rm, ideal_reg);
1327 }