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,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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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/divnode.hpp"
30 #include "opto/machnode.hpp"
31 #include "opto/matcher.hpp"
32 #include "opto/mulnode.hpp"
33 #include "opto/phaseX.hpp"
34 #include "opto/subnode.hpp"
35
36 // Portions of code courtesy of Clifford Click
37
38 // Optimization - Graph Style
39
40 #include <math.h>
41
42 //----------------------magic_int_divide_constants-----------------------------
43 // Compute magic multiplier and shift constant for converting a 32 bit divide
44 // by constant into a multiply/shift/add series. Return false if calculations
45 // fail.
46 //
47 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
48 // minor type name and parameter changes.
49 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
50 int32_t p;
51 uint32_t ad, anc, delta, q1, r1, q2, r2, t;
52 const uint32_t two31 = 0x80000000L; // 2**31.
53
54 ad = ABS(d);
55 if (d == 0 || d == 1) return false;
56 t = two31 + ((uint32_t)d >> 31);
57 anc = t - 1 - t%ad; // Absolute value of nc.
58 p = 31; // Init. p.
59 q1 = two31/anc; // Init. q1 = 2**p/|nc|.
60 r1 = two31 - q1*anc; // Init. r1 = rem(2**p, |nc|).
61 q2 = two31/ad; // Init. q2 = 2**p/|d|.
62 r2 = two31 - q2*ad; // Init. r2 = rem(2**p, |d|).
63 do {
64 p = p + 1;
65 q1 = 2*q1; // Update q1 = 2**p/|nc|.
66 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
67 if (r1 >= anc) { // (Must be an unsigned
68 q1 = q1 + 1; // comparison here).
69 r1 = r1 - anc;
70 }
71 q2 = 2*q2; // Update q2 = 2**p/|d|.
72 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
73 if (r2 >= ad) { // (Must be an unsigned
74 q2 = q2 + 1; // comparison here).
75 r2 = r2 - ad;
76 }
77 delta = ad - r2;
78 } while (q1 < delta || (q1 == delta && r1 == 0));
79
80 M = q2 + 1;
81 if (d < 0) M = -M; // Magic number and
82 s = p - 32; // shift amount to return.
83
84 return true;
85 }
86
87 //--------------------------transform_int_divide-------------------------------
88 // Convert a division by constant divisor into an alternate Ideal graph.
89 // Return NULL if no transformation occurs.
90 static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) {
91
92 // Check for invalid divisors
93 assert( divisor != 0 && divisor != min_jint,
94 "bad divisor for transforming to long multiply" );
95
96 bool d_pos = divisor >= 0;
97 jint d = d_pos ? divisor : -divisor;
98 const int N = 32;
99
100 // Result
101 Node *q = NULL;
102
103 if (d == 1) {
104 // division by +/- 1
105 if (!d_pos) {
106 // Just negate the value
107 q = new (phase->C) SubINode(phase->intcon(0), dividend);
108 }
109 } else if ( is_power_of_2(d) ) {
110 // division by +/- a power of 2
111
112 // See if we can simply do a shift without rounding
113 bool needs_rounding = true;
114 const Type *dt = phase->type(dividend);
115 const TypeInt *dti = dt->isa_int();
116 if (dti && dti->_lo >= 0) {
117 // we don't need to round a positive dividend
118 needs_rounding = false;
119 } else if( dividend->Opcode() == Op_AndI ) {
120 // An AND mask of sufficient size clears the low bits and
121 // I can avoid rounding.
122 const TypeInt *andconi_t = phase->type( dividend->in(2) )->isa_int();
123 if( andconi_t && andconi_t->is_con() ) {
124 jint andconi = andconi_t->get_con();
125 if( andconi < 0 && is_power_of_2(-andconi) && (-andconi) >= d ) {
126 if( (-andconi) == d ) // Remove AND if it clears bits which will be shifted
127 dividend = dividend->in(1);
128 needs_rounding = false;
129 }
130 }
131 }
132
133 // Add rounding to the shift to handle the sign bit
134 int l = log2_intptr(d-1)+1;
135 if (needs_rounding) {
136 // Divide-by-power-of-2 can be made into a shift, but you have to do
137 // more math for the rounding. You need to add 0 for positive
138 // numbers, and "i-1" for negative numbers. Example: i=4, so the
139 // shift is by 2. You need to add 3 to negative dividends and 0 to
140 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
141 // (-2+3)>>2 becomes 0, etc.
142
143 // Compute 0 or -1, based on sign bit
144 Node *sign = phase->transform(new (phase->C) RShiftINode(dividend, phase->intcon(N - 1)));
145 // Mask sign bit to the low sign bits
146 Node *round = phase->transform(new (phase->C) URShiftINode(sign, phase->intcon(N - l)));
147 // Round up before shifting
148 dividend = phase->transform(new (phase->C) AddINode(dividend, round));
149 }
150
151 // Shift for division
152 q = new (phase->C) RShiftINode(dividend, phase->intcon(l));
153
154 if (!d_pos) {
155 q = new (phase->C) SubINode(phase->intcon(0), phase->transform(q));
156 }
157 } else {
158 // Attempt the jint constant divide -> multiply transform found in
159 // "Division by Invariant Integers using Multiplication"
160 // by Granlund and Montgomery
161 // See also "Hacker's Delight", chapter 10 by Warren.
162
163 jint magic_const;
164 jint shift_const;
165 if (magic_int_divide_constants(d, magic_const, shift_const)) {
166 Node *magic = phase->longcon(magic_const);
167 Node *dividend_long = phase->transform(new (phase->C) ConvI2LNode(dividend));
168
169 // Compute the high half of the dividend x magic multiplication
170 Node *mul_hi = phase->transform(new (phase->C) MulLNode(dividend_long, magic));
171
172 if (magic_const < 0) {
173 mul_hi = phase->transform(new (phase->C) RShiftLNode(mul_hi, phase->intcon(N)));
174 mul_hi = phase->transform(new (phase->C) ConvL2INode(mul_hi));
175
176 // The magic multiplier is too large for a 32 bit constant. We've adjusted
177 // it down by 2^32, but have to add 1 dividend back in after the multiplication.
178 // This handles the "overflow" case described by Granlund and Montgomery.
179 mul_hi = phase->transform(new (phase->C) AddINode(dividend, mul_hi));
180
181 // Shift over the (adjusted) mulhi
182 if (shift_const != 0) {
183 mul_hi = phase->transform(new (phase->C) RShiftINode(mul_hi, phase->intcon(shift_const)));
184 }
185 } else {
186 // No add is required, we can merge the shifts together.
187 mul_hi = phase->transform(new (phase->C) RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
188 mul_hi = phase->transform(new (phase->C) ConvL2INode(mul_hi));
189 }
190
191 // Get a 0 or -1 from the sign of the dividend.
192 Node *addend0 = mul_hi;
193 Node *addend1 = phase->transform(new (phase->C) RShiftINode(dividend, phase->intcon(N-1)));
194
195 // If the divisor is negative, swap the order of the input addends;
196 // this has the effect of negating the quotient.
197 if (!d_pos) {
198 Node *temp = addend0; addend0 = addend1; addend1 = temp;
199 }
200
201 // Adjust the final quotient by subtracting -1 (adding 1)
202 // from the mul_hi.
203 q = new (phase->C) SubINode(addend0, addend1);
204 }
205 }
206
207 return q;
208 }
209
210 //---------------------magic_long_divide_constants-----------------------------
211 // Compute magic multiplier and shift constant for converting a 64 bit divide
212 // by constant into a multiply/shift/add series. Return false if calculations
213 // fail.
214 //
215 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
216 // minor type name and parameter changes. Adjusted to 64 bit word width.
217 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) {
218 int64_t p;
219 uint64_t ad, anc, delta, q1, r1, q2, r2, t;
220 const uint64_t two63 = 0x8000000000000000LL; // 2**63.
221
222 ad = ABS(d);
223 if (d == 0 || d == 1) return false;
224 t = two63 + ((uint64_t)d >> 63);
225 anc = t - 1 - t%ad; // Absolute value of nc.
226 p = 63; // Init. p.
227 q1 = two63/anc; // Init. q1 = 2**p/|nc|.
228 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|).
229 q2 = two63/ad; // Init. q2 = 2**p/|d|.
230 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|).
231 do {
232 p = p + 1;
233 q1 = 2*q1; // Update q1 = 2**p/|nc|.
234 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
235 if (r1 >= anc) { // (Must be an unsigned
236 q1 = q1 + 1; // comparison here).
237 r1 = r1 - anc;
238 }
239 q2 = 2*q2; // Update q2 = 2**p/|d|.
240 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
241 if (r2 >= ad) { // (Must be an unsigned
242 q2 = q2 + 1; // comparison here).
243 r2 = r2 - ad;
244 }
245 delta = ad - r2;
246 } while (q1 < delta || (q1 == delta && r1 == 0));
247
248 M = q2 + 1;
249 if (d < 0) M = -M; // Magic number and
250 s = p - 64; // shift amount to return.
251
252 return true;
253 }
254
255 //---------------------long_by_long_mulhi--------------------------------------
256 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication
257 static Node* long_by_long_mulhi(PhaseGVN* phase, Node* dividend, jlong magic_const) {
258 // If the architecture supports a 64x64 mulhi, there is
259 // no need to synthesize it in ideal nodes.
260 if (Matcher::has_match_rule(Op_MulHiL)) {
261 Node* v = phase->longcon(magic_const);
262 return new (phase->C) MulHiLNode(dividend, v);
263 }
264
265 // Taken from Hacker's Delight, Fig. 8-2. Multiply high signed.
266 // (http://www.hackersdelight.org/HDcode/mulhs.c)
267 //
268 // int mulhs(int u, int v) {
269 // unsigned u0, v0, w0;
270 // int u1, v1, w1, w2, t;
271 //
272 // u0 = u & 0xFFFF; u1 = u >> 16;
273 // v0 = v & 0xFFFF; v1 = v >> 16;
274 // w0 = u0*v0;
275 // t = u1*v0 + (w0 >> 16);
276 // w1 = t & 0xFFFF;
277 // w2 = t >> 16;
278 // w1 = u0*v1 + w1;
279 // return u1*v1 + w2 + (w1 >> 16);
280 // }
281 //
282 // Note: The version above is for 32x32 multiplications, while the
283 // following inline comments are adapted to 64x64.
284
285 const int N = 64;
286
287 // Dummy node to keep intermediate nodes alive during construction
288 Node* hook = new (phase->C) Node(4);
289
290 // u0 = u & 0xFFFFFFFF; u1 = u >> 32;
291 Node* u0 = phase->transform(new (phase->C) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
292 Node* u1 = phase->transform(new (phase->C) RShiftLNode(dividend, phase->intcon(N / 2)));
293 hook->init_req(0, u0);
294 hook->init_req(1, u1);
295
296 // v0 = v & 0xFFFFFFFF; v1 = v >> 32;
297 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF);
298 Node* v1 = phase->longcon(magic_const >> (N / 2));
299
300 // w0 = u0*v0;
301 Node* w0 = phase->transform(new (phase->C) MulLNode(u0, v0));
302
303 // t = u1*v0 + (w0 >> 32);
304 Node* u1v0 = phase->transform(new (phase->C) MulLNode(u1, v0));
305 Node* temp = phase->transform(new (phase->C) URShiftLNode(w0, phase->intcon(N / 2)));
306 Node* t = phase->transform(new (phase->C) AddLNode(u1v0, temp));
307 hook->init_req(2, t);
308
309 // w1 = t & 0xFFFFFFFF;
310 Node* w1 = phase->transform(new (phase->C) AndLNode(t, phase->longcon(0xFFFFFFFF)));
311 hook->init_req(3, w1);
312
313 // w2 = t >> 32;
314 Node* w2 = phase->transform(new (phase->C) RShiftLNode(t, phase->intcon(N / 2)));
315
316 // w1 = u0*v1 + w1;
317 Node* u0v1 = phase->transform(new (phase->C) MulLNode(u0, v1));
318 w1 = phase->transform(new (phase->C) AddLNode(u0v1, w1));
319
320 // return u1*v1 + w2 + (w1 >> 32);
321 Node* u1v1 = phase->transform(new (phase->C) MulLNode(u1, v1));
322 Node* temp1 = phase->transform(new (phase->C) AddLNode(u1v1, w2));
323 Node* temp2 = phase->transform(new (phase->C) RShiftLNode(w1, phase->intcon(N / 2)));
324
325 // Remove the bogus extra edges used to keep things alive
326 PhaseIterGVN* igvn = phase->is_IterGVN();
327 if (igvn != NULL) {
328 igvn->remove_dead_node(hook);
329 } else {
330 for (int i = 0; i < 4; i++) {
331 hook->set_req(i, NULL);
332 }
333 }
334
335 return new (phase->C) AddLNode(temp1, temp2);
336 }
337
338
339 //--------------------------transform_long_divide------------------------------
340 // Convert a division by constant divisor into an alternate Ideal graph.
341 // Return NULL if no transformation occurs.
342 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
343 // Check for invalid divisors
344 assert( divisor != 0L && divisor != min_jlong,
345 "bad divisor for transforming to long multiply" );
346
347 bool d_pos = divisor >= 0;
348 jlong d = d_pos ? divisor : -divisor;
349 const int N = 64;
350
351 // Result
352 Node *q = NULL;
353
354 if (d == 1) {
355 // division by +/- 1
356 if (!d_pos) {
357 // Just negate the value
358 q = new (phase->C) SubLNode(phase->longcon(0), dividend);
359 }
360 } else if ( is_power_of_2_long(d) ) {
361
362 // division by +/- a power of 2
363
364 // See if we can simply do a shift without rounding
365 bool needs_rounding = true;
366 const Type *dt = phase->type(dividend);
367 const TypeLong *dtl = dt->isa_long();
368
369 if (dtl && dtl->_lo > 0) {
370 // we don't need to round a positive dividend
371 needs_rounding = false;
372 } else if( dividend->Opcode() == Op_AndL ) {
373 // An AND mask of sufficient size clears the low bits and
374 // I can avoid rounding.
375 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long();
376 if( andconl_t && andconl_t->is_con() ) {
377 jlong andconl = andconl_t->get_con();
378 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) {
379 if( (-andconl) == d ) // Remove AND if it clears bits which will be shifted
380 dividend = dividend->in(1);
381 needs_rounding = false;
382 }
383 }
384 }
385
386 // Add rounding to the shift to handle the sign bit
387 int l = log2_long(d-1)+1;
388 if (needs_rounding) {
389 // Divide-by-power-of-2 can be made into a shift, but you have to do
390 // more math for the rounding. You need to add 0 for positive
391 // numbers, and "i-1" for negative numbers. Example: i=4, so the
392 // shift is by 2. You need to add 3 to negative dividends and 0 to
393 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
394 // (-2+3)>>2 becomes 0, etc.
395
396 // Compute 0 or -1, based on sign bit
397 Node *sign = phase->transform(new (phase->C) RShiftLNode(dividend, phase->intcon(N - 1)));
398 // Mask sign bit to the low sign bits
399 Node *round = phase->transform(new (phase->C) URShiftLNode(sign, phase->intcon(N - l)));
400 // Round up before shifting
401 dividend = phase->transform(new (phase->C) AddLNode(dividend, round));
402 }
403
404 // Shift for division
405 q = new (phase->C) RShiftLNode(dividend, phase->intcon(l));
406
407 if (!d_pos) {
408 q = new (phase->C) SubLNode(phase->longcon(0), phase->transform(q));
409 }
410 } else if ( !Matcher::use_asm_for_ldiv_by_con(d) ) { // Use hardware DIV instruction when
411 // it is faster than code generated below.
412 // Attempt the jlong constant divide -> multiply transform found in
413 // "Division by Invariant Integers using Multiplication"
414 // by Granlund and Montgomery
415 // See also "Hacker's Delight", chapter 10 by Warren.
416
417 jlong magic_const;
418 jint shift_const;
419 if (magic_long_divide_constants(d, magic_const, shift_const)) {
420 // Compute the high half of the dividend x magic multiplication
421 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
422
423 // The high half of the 128-bit multiply is computed.
424 if (magic_const < 0) {
425 // The magic multiplier is too large for a 64 bit constant. We've adjusted
426 // it down by 2^64, but have to add 1 dividend back in after the multiplication.
427 // This handles the "overflow" case described by Granlund and Montgomery.
428 mul_hi = phase->transform(new (phase->C) AddLNode(dividend, mul_hi));
429 }
430
431 // Shift over the (adjusted) mulhi
432 if (shift_const != 0) {
433 mul_hi = phase->transform(new (phase->C) RShiftLNode(mul_hi, phase->intcon(shift_const)));
434 }
435
436 // Get a 0 or -1 from the sign of the dividend.
437 Node *addend0 = mul_hi;
438 Node *addend1 = phase->transform(new (phase->C) RShiftLNode(dividend, phase->intcon(N-1)));
439
440 // If the divisor is negative, swap the order of the input addends;
441 // this has the effect of negating the quotient.
442 if (!d_pos) {
443 Node *temp = addend0; addend0 = addend1; addend1 = temp;
444 }
445
446 // Adjust the final quotient by subtracting -1 (adding 1)
447 // from the mul_hi.
448 q = new (phase->C) SubLNode(addend0, addend1);
449 }
450 }
451
452 return q;
453 }
454
455 //=============================================================================
456 //------------------------------Identity---------------------------------------
457 // If the divisor is 1, we are an identity on the dividend.
458 Node *DivINode::Identity( PhaseTransform *phase ) {
459 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
460 }
461
462 //------------------------------Idealize---------------------------------------
463 // Divides can be changed to multiplies and/or shifts
464 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
465 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
466 // Don't bother trying to transform a dead node
467 if( in(0) && in(0)->is_top() ) return NULL;
468
469 const Type *t = phase->type( in(2) );
470 if( t == TypeInt::ONE ) // Identity?
471 return NULL; // Skip it
472
473 const TypeInt *ti = t->isa_int();
474 if( !ti ) return NULL;
475 if( !ti->is_con() ) return NULL;
476 jint i = ti->get_con(); // Get divisor
477
478 if (i == 0) return NULL; // Dividing by zero constant does not idealize
479
480 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
481
482 // Dividing by MININT does not optimize as a power-of-2 shift.
483 if( i == min_jint ) return NULL;
484
485 return transform_int_divide( phase, in(1), i );
486 }
487
488 //------------------------------Value------------------------------------------
489 // A DivINode divides its inputs. The third input is a Control input, used to
490 // prevent hoisting the divide above an unsafe test.
491 const Type *DivINode::Value( PhaseTransform *phase ) const {
492 // Either input is TOP ==> the result is TOP
493 const Type *t1 = phase->type( in(1) );
494 const Type *t2 = phase->type( in(2) );
495 if( t1 == Type::TOP ) return Type::TOP;
496 if( t2 == Type::TOP ) return Type::TOP;
497
498 // x/x == 1 since we always generate the dynamic divisor check for 0.
499 if( phase->eqv( in(1), in(2) ) )
500 return TypeInt::ONE;
501
502 // Either input is BOTTOM ==> the result is the local BOTTOM
503 const Type *bot = bottom_type();
504 if( (t1 == bot) || (t2 == bot) ||
505 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
506 return bot;
507
508 // Divide the two numbers. We approximate.
509 // If divisor is a constant and not zero
510 const TypeInt *i1 = t1->is_int();
511 const TypeInt *i2 = t2->is_int();
512 int widen = MAX2(i1->_widen, i2->_widen);
513
514 if( i2->is_con() && i2->get_con() != 0 ) {
515 int32 d = i2->get_con(); // Divisor
516 jint lo, hi;
517 if( d >= 0 ) {
518 lo = i1->_lo/d;
519 hi = i1->_hi/d;
520 } else {
521 if( d == -1 && i1->_lo == min_jint ) {
522 // 'min_jint/-1' throws arithmetic exception during compilation
523 lo = min_jint;
524 // do not support holes, 'hi' must go to either min_jint or max_jint:
525 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
526 hi = i1->_hi == min_jint ? min_jint : max_jint;
527 } else {
528 lo = i1->_hi/d;
529 hi = i1->_lo/d;
530 }
531 }
532 return TypeInt::make(lo, hi, widen);
533 }
534
535 // If the dividend is a constant
536 if( i1->is_con() ) {
537 int32 d = i1->get_con();
538 if( d < 0 ) {
539 if( d == min_jint ) {
540 // (-min_jint) == min_jint == (min_jint / -1)
541 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
542 } else {
543 return TypeInt::make(d, -d, widen);
544 }
545 }
546 return TypeInt::make(-d, d, widen);
547 }
548
549 // Otherwise we give up all hope
550 return TypeInt::INT;
551 }
552
553
554 //=============================================================================
555 //------------------------------Identity---------------------------------------
556 // If the divisor is 1, we are an identity on the dividend.
557 Node *DivLNode::Identity( PhaseTransform *phase ) {
558 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
559 }
560
561 //------------------------------Idealize---------------------------------------
562 // Dividing by a power of 2 is a shift.
563 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
564 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
565 // Don't bother trying to transform a dead node
566 if( in(0) && in(0)->is_top() ) return NULL;
567
568 const Type *t = phase->type( in(2) );
569 if( t == TypeLong::ONE ) // Identity?
570 return NULL; // Skip it
571
572 const TypeLong *tl = t->isa_long();
573 if( !tl ) return NULL;
574 if( !tl->is_con() ) return NULL;
575 jlong l = tl->get_con(); // Get divisor
576
577 if (l == 0) return NULL; // Dividing by zero constant does not idealize
578
579 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
580
581 // Dividing by MINLONG does not optimize as a power-of-2 shift.
582 if( l == min_jlong ) return NULL;
583
584 return transform_long_divide( phase, in(1), l );
585 }
586
587 //------------------------------Value------------------------------------------
588 // A DivLNode divides its inputs. The third input is a Control input, used to
589 // prevent hoisting the divide above an unsafe test.
590 const Type *DivLNode::Value( PhaseTransform *phase ) const {
591 // Either input is TOP ==> the result is TOP
592 const Type *t1 = phase->type( in(1) );
593 const Type *t2 = phase->type( in(2) );
594 if( t1 == Type::TOP ) return Type::TOP;
595 if( t2 == Type::TOP ) return Type::TOP;
596
597 // x/x == 1 since we always generate the dynamic divisor check for 0.
598 if( phase->eqv( in(1), in(2) ) )
599 return TypeLong::ONE;
600
601 // Either input is BOTTOM ==> the result is the local BOTTOM
602 const Type *bot = bottom_type();
603 if( (t1 == bot) || (t2 == bot) ||
604 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
605 return bot;
606
607 // Divide the two numbers. We approximate.
608 // If divisor is a constant and not zero
609 const TypeLong *i1 = t1->is_long();
610 const TypeLong *i2 = t2->is_long();
611 int widen = MAX2(i1->_widen, i2->_widen);
612
613 if( i2->is_con() && i2->get_con() != 0 ) {
614 jlong d = i2->get_con(); // Divisor
615 jlong lo, hi;
616 if( d >= 0 ) {
617 lo = i1->_lo/d;
618 hi = i1->_hi/d;
619 } else {
620 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
621 // 'min_jlong/-1' throws arithmetic exception during compilation
622 lo = min_jlong;
623 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
624 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
625 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
626 } else {
627 lo = i1->_hi/d;
628 hi = i1->_lo/d;
629 }
630 }
631 return TypeLong::make(lo, hi, widen);
632 }
633
634 // If the dividend is a constant
635 if( i1->is_con() ) {
636 jlong d = i1->get_con();
637 if( d < 0 ) {
638 if( d == min_jlong ) {
639 // (-min_jlong) == min_jlong == (min_jlong / -1)
640 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
641 } else {
642 return TypeLong::make(d, -d, widen);
643 }
644 }
645 return TypeLong::make(-d, d, widen);
646 }
647
648 // Otherwise we give up all hope
649 return TypeLong::LONG;
650 }
651
652
653 //=============================================================================
654 //------------------------------Value------------------------------------------
655 // An DivFNode divides its inputs. The third input is a Control input, used to
656 // prevent hoisting the divide above an unsafe test.
657 const Type *DivFNode::Value( PhaseTransform *phase ) const {
658 // Either input is TOP ==> the result is TOP
659 const Type *t1 = phase->type( in(1) );
660 const Type *t2 = phase->type( in(2) );
661 if( t1 == Type::TOP ) return Type::TOP;
662 if( t2 == Type::TOP ) return Type::TOP;
663
664 // Either input is BOTTOM ==> the result is the local BOTTOM
665 const Type *bot = bottom_type();
666 if( (t1 == bot) || (t2 == bot) ||
667 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
668 return bot;
669
670 // x/x == 1, we ignore 0/0.
671 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
672 // Does not work for variables because of NaN's
673 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
674 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
675 return TypeF::ONE;
676
677 if( t2 == TypeF::ONE )
678 return t1;
679
680 // If divisor is a constant and not zero, divide them numbers
681 if( t1->base() == Type::FloatCon &&
682 t2->base() == Type::FloatCon &&
683 t2->getf() != 0.0 ) // could be negative zero
684 return TypeF::make( t1->getf()/t2->getf() );
685
686 // If the dividend is a constant zero
687 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
688 // Test TypeF::ZERO is not sufficient as it could be negative zero
689
690 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
691 return TypeF::ZERO;
692
693 // Otherwise we give up all hope
694 return Type::FLOAT;
695 }
696
697 //------------------------------isA_Copy---------------------------------------
698 // Dividing by self is 1.
699 // If the divisor is 1, we are an identity on the dividend.
700 Node *DivFNode::Identity( PhaseTransform *phase ) {
701 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
702 }
703
704
705 //------------------------------Idealize---------------------------------------
706 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
707 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
708 // Don't bother trying to transform a dead node
709 if( in(0) && in(0)->is_top() ) return NULL;
710
711 const Type *t2 = phase->type( in(2) );
712 if( t2 == TypeF::ONE ) // Identity?
713 return NULL; // Skip it
714
715 const TypeF *tf = t2->isa_float_constant();
716 if( !tf ) return NULL;
717 if( tf->base() != Type::FloatCon ) return NULL;
718
719 // Check for out of range values
720 if( tf->is_nan() || !tf->is_finite() ) return NULL;
721
722 // Get the value
723 float f = tf->getf();
724 int exp;
725
726 // Only for special case of dividing by a power of 2
727 if( frexp((double)f, &exp) != 0.5 ) return NULL;
728
729 // Limit the range of acceptable exponents
730 if( exp < -126 || exp > 126 ) return NULL;
731
732 // Compute the reciprocal
733 float reciprocal = ((float)1.0) / f;
734
735 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
736
737 // return multiplication by the reciprocal
738 return (new (phase->C) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
739 }
740
741 //=============================================================================
742 //------------------------------Value------------------------------------------
743 // An DivDNode divides its inputs. The third input is a Control input, used to
744 // prevent hoisting the divide above an unsafe test.
745 const Type *DivDNode::Value( PhaseTransform *phase ) const {
746 // Either input is TOP ==> the result is TOP
747 const Type *t1 = phase->type( in(1) );
748 const Type *t2 = phase->type( in(2) );
749 if( t1 == Type::TOP ) return Type::TOP;
750 if( t2 == Type::TOP ) return Type::TOP;
751
752 // Either input is BOTTOM ==> the result is the local BOTTOM
753 const Type *bot = bottom_type();
754 if( (t1 == bot) || (t2 == bot) ||
755 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
756 return bot;
757
758 // x/x == 1, we ignore 0/0.
759 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
760 // Does not work for variables because of NaN's
761 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
762 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
763 return TypeD::ONE;
764
765 if( t2 == TypeD::ONE )
766 return t1;
767
768 #if defined(IA32)
769 if (!phase->C->method()->is_strict())
770 // Can't trust native compilers to properly fold strict double
771 // division with round-to-zero on this platform.
772 #endif
773 {
774 // If divisor is a constant and not zero, divide them numbers
775 if( t1->base() == Type::DoubleCon &&
776 t2->base() == Type::DoubleCon &&
777 t2->getd() != 0.0 ) // could be negative zero
778 return TypeD::make( t1->getd()/t2->getd() );
779 }
780
781 // If the dividend is a constant zero
782 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
783 // Test TypeF::ZERO is not sufficient as it could be negative zero
784 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
785 return TypeD::ZERO;
786
787 // Otherwise we give up all hope
788 return Type::DOUBLE;
789 }
790
791
792 //------------------------------isA_Copy---------------------------------------
793 // Dividing by self is 1.
794 // If the divisor is 1, we are an identity on the dividend.
795 Node *DivDNode::Identity( PhaseTransform *phase ) {
796 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
797 }
798
799 //------------------------------Idealize---------------------------------------
800 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
801 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
802 // Don't bother trying to transform a dead node
803 if( in(0) && in(0)->is_top() ) return NULL;
804
805 const Type *t2 = phase->type( in(2) );
806 if( t2 == TypeD::ONE ) // Identity?
807 return NULL; // Skip it
808
809 const TypeD *td = t2->isa_double_constant();
810 if( !td ) return NULL;
811 if( td->base() != Type::DoubleCon ) return NULL;
812
813 // Check for out of range values
814 if( td->is_nan() || !td->is_finite() ) return NULL;
815
816 // Get the value
817 double d = td->getd();
818 int exp;
819
820 // Only for special case of dividing by a power of 2
821 if( frexp(d, &exp) != 0.5 ) return NULL;
822
823 // Limit the range of acceptable exponents
824 if( exp < -1021 || exp > 1022 ) return NULL;
825
826 // Compute the reciprocal
827 double reciprocal = 1.0 / d;
828
829 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
830
831 // return multiplication by the reciprocal
832 return (new (phase->C) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
833 }
834
835 //=============================================================================
836 //------------------------------Idealize---------------------------------------
837 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
838 // Check for dead control input
839 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
840 // Don't bother trying to transform a dead node
841 if( in(0) && in(0)->is_top() ) return NULL;
842
843 // Get the modulus
844 const Type *t = phase->type( in(2) );
845 if( t == Type::TOP ) return NULL;
846 const TypeInt *ti = t->is_int();
847
848 // Check for useless control input
849 // Check for excluding mod-zero case
850 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
851 set_req(0, NULL); // Yank control input
852 return this;
853 }
854
855 // See if we are MOD'ing by 2^k or 2^k-1.
856 if( !ti->is_con() ) return NULL;
857 jint con = ti->get_con();
858
859 Node *hook = new (phase->C) Node(1);
860
861 // First, special check for modulo 2^k-1
862 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
863 uint k = exact_log2(con+1); // Extract k
864
865 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
866 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*/};
867 int trip_count = 1;
868 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
869
870 // If the unroll factor is not too large, and if conditional moves are
871 // ok, then use this case
872 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
873 Node *x = in(1); // Value being mod'd
874 Node *divisor = in(2); // Also is mask
875
876 hook->init_req(0, x); // Add a use to x to prevent him from dying
877 // Generate code to reduce X rapidly to nearly 2^k-1.
878 for( int i = 0; i < trip_count; i++ ) {
879 Node *xl = phase->transform( new (phase->C) AndINode(x,divisor) );
880 Node *xh = phase->transform( new (phase->C) RShiftINode(x,phase->intcon(k)) ); // Must be signed
881 x = phase->transform( new (phase->C) AddINode(xh,xl) );
882 hook->set_req(0, x);
883 }
884
885 // Generate sign-fixup code. Was original value positive?
886 // int hack_res = (i >= 0) ? divisor : 1;
887 Node *cmp1 = phase->transform( new (phase->C) CmpINode( in(1), phase->intcon(0) ) );
888 Node *bol1 = phase->transform( new (phase->C) BoolNode( cmp1, BoolTest::ge ) );
889 Node *cmov1= phase->transform( new (phase->C) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
890 // if( x >= hack_res ) x -= divisor;
891 Node *sub = phase->transform( new (phase->C) SubINode( x, divisor ) );
892 Node *cmp2 = phase->transform( new (phase->C) CmpINode( x, cmov1 ) );
893 Node *bol2 = phase->transform( new (phase->C) BoolNode( cmp2, BoolTest::ge ) );
894 // Convention is to not transform the return value of an Ideal
895 // since Ideal is expected to return a modified 'this' or a new node.
896 Node *cmov2= new (phase->C) CMoveINode(bol2, x, sub, TypeInt::INT);
897 // cmov2 is now the mod
898
899 // Now remove the bogus extra edges used to keep things alive
900 if (can_reshape) {
901 phase->is_IterGVN()->remove_dead_node(hook);
902 } else {
903 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
904 }
905 return cmov2;
906 }
907 }
908
909 // Fell thru, the unroll case is not appropriate. Transform the modulo
910 // into a long multiply/int multiply/subtract case
911
912 // Cannot handle mod 0, and min_jint isn't handled by the transform
913 if( con == 0 || con == min_jint ) return NULL;
914
915 // Get the absolute value of the constant; at this point, we can use this
916 jint pos_con = (con >= 0) ? con : -con;
917
918 // integer Mod 1 is always 0
919 if( pos_con == 1 ) return new (phase->C) ConINode(TypeInt::ZERO);
920
921 int log2_con = -1;
922
923 // If this is a power of two, they maybe we can mask it
924 if( is_power_of_2(pos_con) ) {
925 log2_con = log2_intptr((intptr_t)pos_con);
926
927 const Type *dt = phase->type(in(1));
928 const TypeInt *dti = dt->isa_int();
929
930 // See if this can be masked, if the dividend is non-negative
931 if( dti && dti->_lo >= 0 )
932 return ( new (phase->C) AndINode( in(1), phase->intcon( pos_con-1 ) ) );
933 }
934
935 // Save in(1) so that it cannot be changed or deleted
936 hook->init_req(0, in(1));
937
938 // Divide using the transform from DivI to MulL
939 Node *result = transform_int_divide( phase, in(1), pos_con );
940 if (result != NULL) {
941 Node *divide = phase->transform(result);
942
943 // Re-multiply, using a shift if this is a power of two
944 Node *mult = NULL;
945
946 if( log2_con >= 0 )
947 mult = phase->transform( new (phase->C) LShiftINode( divide, phase->intcon( log2_con ) ) );
948 else
949 mult = phase->transform( new (phase->C) MulINode( divide, phase->intcon( pos_con ) ) );
950
951 // Finally, subtract the multiplied divided value from the original
952 result = new (phase->C) SubINode( in(1), mult );
953 }
954
955 // Now remove the bogus extra edges used to keep things alive
956 if (can_reshape) {
957 phase->is_IterGVN()->remove_dead_node(hook);
958 } else {
959 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
960 }
961
962 // return the value
963 return result;
964 }
965
966 //------------------------------Value------------------------------------------
967 const Type *ModINode::Value( PhaseTransform *phase ) const {
968 // Either input is TOP ==> the result is TOP
969 const Type *t1 = phase->type( in(1) );
970 const Type *t2 = phase->type( in(2) );
971 if( t1 == Type::TOP ) return Type::TOP;
972 if( t2 == Type::TOP ) return Type::TOP;
973
974 // We always generate the dynamic check for 0.
975 // 0 MOD X is 0
976 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
977 // X MOD X is 0
978 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
979
980 // Either input is BOTTOM ==> the result is the local BOTTOM
981 const Type *bot = bottom_type();
982 if( (t1 == bot) || (t2 == bot) ||
983 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
984 return bot;
985
986 const TypeInt *i1 = t1->is_int();
987 const TypeInt *i2 = t2->is_int();
988 if( !i1->is_con() || !i2->is_con() ) {
989 if( i1->_lo >= 0 && i2->_lo >= 0 )
990 return TypeInt::POS;
991 // If both numbers are not constants, we know little.
992 return TypeInt::INT;
993 }
994 // Mod by zero? Throw exception at runtime!
995 if( !i2->get_con() ) return TypeInt::POS;
996
997 // We must be modulo'ing 2 float constants.
998 // Check for min_jint % '-1', result is defined to be '0'.
999 if( i1->get_con() == min_jint && i2->get_con() == -1 )
1000 return TypeInt::ZERO;
1001
1002 return TypeInt::make( i1->get_con() % i2->get_con() );
1003 }
1004
1005
1006 //=============================================================================
1007 //------------------------------Idealize---------------------------------------
1008 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1009 // Check for dead control input
1010 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
1011 // Don't bother trying to transform a dead node
1012 if( in(0) && in(0)->is_top() ) return NULL;
1013
1014 // Get the modulus
1015 const Type *t = phase->type( in(2) );
1016 if( t == Type::TOP ) return NULL;
1017 const TypeLong *tl = t->is_long();
1018
1019 // Check for useless control input
1020 // Check for excluding mod-zero case
1021 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
1022 set_req(0, NULL); // Yank control input
1023 return this;
1024 }
1025
1026 // See if we are MOD'ing by 2^k or 2^k-1.
1027 if( !tl->is_con() ) return NULL;
1028 jlong con = tl->get_con();
1029
1030 Node *hook = new (phase->C) Node(1);
1031
1032 // Expand mod
1033 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
1034 uint k = exact_log2_long(con+1); // Extract k
1035
1036 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
1037 // Used to help a popular random number generator which does a long-mod
1038 // of 2^31-1 and shows up in SpecJBB and SciMark.
1039 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*/};
1040 int trip_count = 1;
1041 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
1042
1043 // If the unroll factor is not too large, and if conditional moves are
1044 // ok, then use this case
1045 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
1046 Node *x = in(1); // Value being mod'd
1047 Node *divisor = in(2); // Also is mask
1048
1049 hook->init_req(0, x); // Add a use to x to prevent him from dying
1050 // Generate code to reduce X rapidly to nearly 2^k-1.
1051 for( int i = 0; i < trip_count; i++ ) {
1052 Node *xl = phase->transform( new (phase->C) AndLNode(x,divisor) );
1053 Node *xh = phase->transform( new (phase->C) RShiftLNode(x,phase->intcon(k)) ); // Must be signed
1054 x = phase->transform( new (phase->C) AddLNode(xh,xl) );
1055 hook->set_req(0, x); // Add a use to x to prevent him from dying
1056 }
1057
1058 // Generate sign-fixup code. Was original value positive?
1059 // long hack_res = (i >= 0) ? divisor : CONST64(1);
1060 Node *cmp1 = phase->transform( new (phase->C) CmpLNode( in(1), phase->longcon(0) ) );
1061 Node *bol1 = phase->transform( new (phase->C) BoolNode( cmp1, BoolTest::ge ) );
1062 Node *cmov1= phase->transform( new (phase->C) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
1063 // if( x >= hack_res ) x -= divisor;
1064 Node *sub = phase->transform( new (phase->C) SubLNode( x, divisor ) );
1065 Node *cmp2 = phase->transform( new (phase->C) CmpLNode( x, cmov1 ) );
1066 Node *bol2 = phase->transform( new (phase->C) BoolNode( cmp2, BoolTest::ge ) );
1067 // Convention is to not transform the return value of an Ideal
1068 // since Ideal is expected to return a modified 'this' or a new node.
1069 Node *cmov2= new (phase->C) CMoveLNode(bol2, x, sub, TypeLong::LONG);
1070 // cmov2 is now the mod
1071
1072 // Now remove the bogus extra edges used to keep things alive
1073 if (can_reshape) {
1074 phase->is_IterGVN()->remove_dead_node(hook);
1075 } else {
1076 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1077 }
1078 return cmov2;
1079 }
1080 }
1081
1082 // Fell thru, the unroll case is not appropriate. Transform the modulo
1083 // into a long multiply/int multiply/subtract case
1084
1085 // Cannot handle mod 0, and min_jlong isn't handled by the transform
1086 if( con == 0 || con == min_jlong ) return NULL;
1087
1088 // Get the absolute value of the constant; at this point, we can use this
1089 jlong pos_con = (con >= 0) ? con : -con;
1090
1091 // integer Mod 1 is always 0
1092 if( pos_con == 1 ) return new (phase->C) ConLNode(TypeLong::ZERO);
1093
1094 int log2_con = -1;
1095
1096 // If this is a power of two, then maybe we can mask it
1097 if( is_power_of_2_long(pos_con) ) {
1098 log2_con = exact_log2_long(pos_con);
1099
1100 const Type *dt = phase->type(in(1));
1101 const TypeLong *dtl = dt->isa_long();
1102
1103 // See if this can be masked, if the dividend is non-negative
1104 if( dtl && dtl->_lo >= 0 )
1105 return ( new (phase->C) AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1106 }
1107
1108 // Save in(1) so that it cannot be changed or deleted
1109 hook->init_req(0, in(1));
1110
1111 // Divide using the transform from DivL to MulL
1112 Node *result = transform_long_divide( phase, in(1), pos_con );
1113 if (result != NULL) {
1114 Node *divide = phase->transform(result);
1115
1116 // Re-multiply, using a shift if this is a power of two
1117 Node *mult = NULL;
1118
1119 if( log2_con >= 0 )
1120 mult = phase->transform( new (phase->C) LShiftLNode( divide, phase->intcon( log2_con ) ) );
1121 else
1122 mult = phase->transform( new (phase->C) MulLNode( divide, phase->longcon( pos_con ) ) );
1123
1124 // Finally, subtract the multiplied divided value from the original
1125 result = new (phase->C) SubLNode( in(1), mult );
1126 }
1127
1128 // Now remove the bogus extra edges used to keep things alive
1129 if (can_reshape) {
1130 phase->is_IterGVN()->remove_dead_node(hook);
1131 } else {
1132 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1133 }
1134
1135 // return the value
1136 return result;
1137 }
1138
1139 //------------------------------Value------------------------------------------
1140 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1141 // Either input is TOP ==> the result is TOP
1142 const Type *t1 = phase->type( in(1) );
1143 const Type *t2 = phase->type( in(2) );
1144 if( t1 == Type::TOP ) return Type::TOP;
1145 if( t2 == Type::TOP ) return Type::TOP;
1146
1147 // We always generate the dynamic check for 0.
1148 // 0 MOD X is 0
1149 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1150 // X MOD X is 0
1151 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1152
1153 // Either input is BOTTOM ==> the result is the local BOTTOM
1154 const Type *bot = bottom_type();
1155 if( (t1 == bot) || (t2 == bot) ||
1156 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1157 return bot;
1158
1159 const TypeLong *i1 = t1->is_long();
1160 const TypeLong *i2 = t2->is_long();
1161 if( !i1->is_con() || !i2->is_con() ) {
1162 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1163 return TypeLong::POS;
1164 // If both numbers are not constants, we know little.
1165 return TypeLong::LONG;
1166 }
1167 // Mod by zero? Throw exception at runtime!
1168 if( !i2->get_con() ) return TypeLong::POS;
1169
1170 // We must be modulo'ing 2 float constants.
1171 // Check for min_jint % '-1', result is defined to be '0'.
1172 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1173 return TypeLong::ZERO;
1174
1175 return TypeLong::make( i1->get_con() % i2->get_con() );
1176 }
1177
1178
1179 //=============================================================================
1180 //------------------------------Value------------------------------------------
1181 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1182 // Either input is TOP ==> the result is TOP
1183 const Type *t1 = phase->type( in(1) );
1184 const Type *t2 = phase->type( in(2) );
1185 if( t1 == Type::TOP ) return Type::TOP;
1186 if( t2 == Type::TOP ) return Type::TOP;
1187
1188 // Either input is BOTTOM ==> the result is the local BOTTOM
1189 const Type *bot = bottom_type();
1190 if( (t1 == bot) || (t2 == bot) ||
1191 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1192 return bot;
1193
1194 // If either number is not a constant, we know nothing.
1195 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1196 return Type::FLOAT; // note: x%x can be either NaN or 0
1197 }
1198
1199 float f1 = t1->getf();
1200 float f2 = t2->getf();
1201 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1202 jint x2 = jint_cast(f2);
1203
1204 // If either is a NaN, return an input NaN
1205 if (g_isnan(f1)) return t1;
1206 if (g_isnan(f2)) return t2;
1207
1208 // If an operand is infinity or the divisor is +/- zero, punt.
1209 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1210 return Type::FLOAT;
1211
1212 // We must be modulo'ing 2 float constants.
1213 // Make sure that the sign of the fmod is equal to the sign of the dividend
1214 jint xr = jint_cast(fmod(f1, f2));
1215 if ((x1 ^ xr) < 0) {
1216 xr ^= min_jint;
1217 }
1218
1219 return TypeF::make(jfloat_cast(xr));
1220 }
1221
1222
1223 //=============================================================================
1224 //------------------------------Value------------------------------------------
1225 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1226 // Either input is TOP ==> the result is TOP
1227 const Type *t1 = phase->type( in(1) );
1228 const Type *t2 = phase->type( in(2) );
1229 if( t1 == Type::TOP ) return Type::TOP;
1230 if( t2 == Type::TOP ) return Type::TOP;
1231
1232 // Either input is BOTTOM ==> the result is the local BOTTOM
1233 const Type *bot = bottom_type();
1234 if( (t1 == bot) || (t2 == bot) ||
1235 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1236 return bot;
1237
1238 // If either number is not a constant, we know nothing.
1239 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1240 return Type::DOUBLE; // note: x%x can be either NaN or 0
1241 }
1242
1243 double f1 = t1->getd();
1244 double f2 = t2->getd();
1245 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1246 jlong x2 = jlong_cast(f2);
1247
1248 // If either is a NaN, return an input NaN
1249 if (g_isnan(f1)) return t1;
1250 if (g_isnan(f2)) return t2;
1251
1252 // If an operand is infinity or the divisor is +/- zero, punt.
1253 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1254 return Type::DOUBLE;
1255
1256 // We must be modulo'ing 2 double constants.
1257 // Make sure that the sign of the fmod is equal to the sign of the dividend
1258 jlong xr = jlong_cast(fmod(f1, f2));
1259 if ((x1 ^ xr) < 0) {
1260 xr ^= min_jlong;
1261 }
1262
1263 return TypeD::make(jdouble_cast(xr));
1264 }
1265
1266 //=============================================================================
1267
1268 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1269 init_req(0, c);
1270 init_req(1, dividend);
1271 init_req(2, divisor);
1272 }
1273
1274 //------------------------------make------------------------------------------
1275 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
1276 Node* n = div_or_mod;
1277 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1278 "only div or mod input pattern accepted");
1279
1280 DivModINode* divmod = new (C) DivModINode(n->in(0), n->in(1), n->in(2));
1281 Node* dproj = new (C) ProjNode(divmod, DivModNode::div_proj_num);
1282 Node* mproj = new (C) ProjNode(divmod, DivModNode::mod_proj_num);
1283 return divmod;
1284 }
1285
1286 //------------------------------make------------------------------------------
1287 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
1288 Node* n = div_or_mod;
1289 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1290 "only div or mod input pattern accepted");
1291
1292 DivModLNode* divmod = new (C) DivModLNode(n->in(0), n->in(1), n->in(2));
1293 Node* dproj = new (C) ProjNode(divmod, DivModNode::div_proj_num);
1294 Node* mproj = new (C) ProjNode(divmod, DivModNode::mod_proj_num);
1295 return divmod;
1296 }
1297
1298 //------------------------------match------------------------------------------
1299 // return result(s) along with their RegMask info
1300 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1301 uint ideal_reg = proj->ideal_reg();
1302 RegMask rm;
1303 if (proj->_con == div_proj_num) {
1304 rm = match->divI_proj_mask();
1305 } else {
1306 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1307 rm = match->modI_proj_mask();
1308 }
1309 return new (match->C)MachProjNode(this, proj->_con, rm, ideal_reg);
1310 }
1311
1312
1313 //------------------------------match------------------------------------------
1314 // return result(s) along with their RegMask info
1315 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1316 uint ideal_reg = proj->ideal_reg();
1317 RegMask rm;
1318 if (proj->_con == div_proj_num) {
1319 rm = match->divL_proj_mask();
1320 } else {
1321 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1322 rm = match->modL_proj_mask();
1323 }
1324 return new (match->C)MachProjNode(this, proj->_con, rm, ideal_reg);
1325 }