1 /*
2 * Copyright (c) 1997, 2010, 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, 3) 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, 3) RShiftINode(dividend, phase->intcon(N - 1)));
145 // Mask sign bit to the low sign bits
146 Node *round = phase->transform(new (phase->C, 3) URShiftINode(sign, phase->intcon(N - l)));
147 // Round up before shifting
148 dividend = phase->transform(new (phase->C, 3) AddINode(dividend, round));
149 }
150
151 // Shift for division
152 q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l));
153
154 if (!d_pos) {
155 q = new (phase->C, 3) 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, 2) ConvI2LNode(dividend));
168
169 // Compute the high half of the dividend x magic multiplication
170 Node *mul_hi = phase->transform(new (phase->C, 3) MulLNode(dividend_long, magic));
171
172 if (magic_const < 0) {
173 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N)));
174 mul_hi = phase->transform(new (phase->C, 2) 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, 3) AddINode(dividend, mul_hi));
180
181 // Shift over the (adjusted) mulhi
182 if (shift_const != 0) {
183 mul_hi = phase->transform(new (phase->C, 3) 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, 3) RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
188 mul_hi = phase->transform(new (phase->C, 2) 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, 3) 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, 3) 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, 3) 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 // u0 = u & 0xFFFFFFFF; u1 = u >> 32;
288 Node* u0 = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
289 Node* u1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2)));
290
291 // v0 = v & 0xFFFFFFFF; v1 = v >> 32;
292 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF);
293 Node* v1 = phase->longcon(magic_const >> (N / 2));
294
295 // w0 = u0*v0;
296 Node* w0 = phase->transform(new (phase->C, 3) MulLNode(u0, v0));
297
298 // t = u1*v0 + (w0 >> 32);
299 Node* u1v0 = phase->transform(new (phase->C, 3) MulLNode(u1, v0));
300 Node* temp = phase->transform(new (phase->C, 3) URShiftLNode(w0, phase->intcon(N / 2)));
301 Node* t = phase->transform(new (phase->C, 3) AddLNode(u1v0, temp));
302
303 // w1 = t & 0xFFFFFFFF;
304 Node* w1 = new (phase->C, 3) AndLNode(t, phase->longcon(0xFFFFFFFF));
305
306 // w2 = t >> 32;
307 Node* w2 = new (phase->C, 3) RShiftLNode(t, phase->intcon(N / 2));
308
309 // 6732154: Construct both w1 and w2 before transforming, so t
310 // doesn't go dead prematurely.
311 // 6837011: We need to transform w2 before w1 because the
312 // transformation of w1 could return t.
313 w2 = phase->transform(w2);
314 w1 = phase->transform(w1);
315
316 // w1 = u0*v1 + w1;
317 Node* u0v1 = phase->transform(new (phase->C, 3) MulLNode(u0, v1));
318 w1 = phase->transform(new (phase->C, 3) AddLNode(u0v1, w1));
319
320 // return u1*v1 + w2 + (w1 >> 32);
321 Node* u1v1 = phase->transform(new (phase->C, 3) MulLNode(u1, v1));
322 Node* temp1 = phase->transform(new (phase->C, 3) AddLNode(u1v1, w2));
323 Node* temp2 = phase->transform(new (phase->C, 3) RShiftLNode(w1, phase->intcon(N / 2)));
324
325 return new (phase->C, 3) AddLNode(temp1, temp2);
326 }
327
328
329 //--------------------------transform_long_divide------------------------------
330 // Convert a division by constant divisor into an alternate Ideal graph.
331 // Return NULL if no transformation occurs.
332 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
333 // Check for invalid divisors
334 assert( divisor != 0L && divisor != min_jlong,
335 "bad divisor for transforming to long multiply" );
336
337 bool d_pos = divisor >= 0;
338 jlong d = d_pos ? divisor : -divisor;
339 const int N = 64;
340
341 // Result
342 Node *q = NULL;
343
344 if (d == 1) {
345 // division by +/- 1
346 if (!d_pos) {
347 // Just negate the value
348 q = new (phase->C, 3) SubLNode(phase->longcon(0), dividend);
349 }
350 } else if ( is_power_of_2_long(d) ) {
351
352 // division by +/- a power of 2
353
354 // See if we can simply do a shift without rounding
355 bool needs_rounding = true;
356 const Type *dt = phase->type(dividend);
357 const TypeLong *dtl = dt->isa_long();
358
359 if (dtl && dtl->_lo > 0) {
360 // we don't need to round a positive dividend
361 needs_rounding = false;
362 } else if( dividend->Opcode() == Op_AndL ) {
363 // An AND mask of sufficient size clears the low bits and
364 // I can avoid rounding.
365 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long();
366 if( andconl_t && andconl_t->is_con() ) {
367 jlong andconl = andconl_t->get_con();
368 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) {
369 if( (-andconl) == d ) // Remove AND if it clears bits which will be shifted
370 dividend = dividend->in(1);
371 needs_rounding = false;
372 }
373 }
374 }
375
376 // Add rounding to the shift to handle the sign bit
377 int l = log2_long(d-1)+1;
378 if (needs_rounding) {
379 // Divide-by-power-of-2 can be made into a shift, but you have to do
380 // more math for the rounding. You need to add 0 for positive
381 // numbers, and "i-1" for negative numbers. Example: i=4, so the
382 // shift is by 2. You need to add 3 to negative dividends and 0 to
383 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
384 // (-2+3)>>2 becomes 0, etc.
385
386 // Compute 0 or -1, based on sign bit
387 Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N - 1)));
388 // Mask sign bit to the low sign bits
389 Node *round = phase->transform(new (phase->C, 3) URShiftLNode(sign, phase->intcon(N - l)));
390 // Round up before shifting
391 dividend = phase->transform(new (phase->C, 3) AddLNode(dividend, round));
392 }
393
394 // Shift for division
395 q = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(l));
396
397 if (!d_pos) {
398 q = new (phase->C, 3) SubLNode(phase->longcon(0), phase->transform(q));
399 }
400 } else {
401 // Attempt the jlong constant divide -> multiply transform found in
402 // "Division by Invariant Integers using Multiplication"
403 // by Granlund and Montgomery
404 // See also "Hacker's Delight", chapter 10 by Warren.
405
406 jlong magic_const;
407 jint shift_const;
408 if (magic_long_divide_constants(d, magic_const, shift_const)) {
409 // Compute the high half of the dividend x magic multiplication
410 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
411
412 // The high half of the 128-bit multiply is computed.
413 if (magic_const < 0) {
414 // The magic multiplier is too large for a 64 bit constant. We've adjusted
415 // it down by 2^64, but have to add 1 dividend back in after the multiplication.
416 // This handles the "overflow" case described by Granlund and Montgomery.
417 mul_hi = phase->transform(new (phase->C, 3) AddLNode(dividend, mul_hi));
418 }
419
420 // Shift over the (adjusted) mulhi
421 if (shift_const != 0) {
422 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(shift_const)));
423 }
424
425 // Get a 0 or -1 from the sign of the dividend.
426 Node *addend0 = mul_hi;
427 Node *addend1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N-1)));
428
429 // If the divisor is negative, swap the order of the input addends;
430 // this has the effect of negating the quotient.
431 if (!d_pos) {
432 Node *temp = addend0; addend0 = addend1; addend1 = temp;
433 }
434
435 // Adjust the final quotient by subtracting -1 (adding 1)
436 // from the mul_hi.
437 q = new (phase->C, 3) SubLNode(addend0, addend1);
438 }
439 }
440
441 return q;
442 }
443
444 //=============================================================================
445 //------------------------------Identity---------------------------------------
446 // If the divisor is 1, we are an identity on the dividend.
447 Node *DivINode::Identity( PhaseTransform *phase ) {
448 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
449 }
450
451 //------------------------------Idealize---------------------------------------
452 // Divides can be changed to multiplies and/or shifts
453 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
454 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
455 // Don't bother trying to transform a dead node
456 if( in(0) && in(0)->is_top() ) return NULL;
457
458 const Type *t = phase->type( in(2) );
459 if( t == TypeInt::ONE ) // Identity?
460 return NULL; // Skip it
461
462 const TypeInt *ti = t->isa_int();
463 if( !ti ) return NULL;
464 if( !ti->is_con() ) return NULL;
465 jint i = ti->get_con(); // Get divisor
466
467 if (i == 0) return NULL; // Dividing by zero constant does not idealize
468
469 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
470
471 // Dividing by MININT does not optimize as a power-of-2 shift.
472 if( i == min_jint ) return NULL;
473
474 return transform_int_divide( phase, in(1), i );
475 }
476
477 //------------------------------Value------------------------------------------
478 // A DivINode divides its inputs. The third input is a Control input, used to
479 // prevent hoisting the divide above an unsafe test.
480 const Type *DivINode::Value( PhaseTransform *phase ) const {
481 // Either input is TOP ==> the result is TOP
482 const Type *t1 = phase->type( in(1) );
483 const Type *t2 = phase->type( in(2) );
484 if( t1 == Type::TOP ) return Type::TOP;
485 if( t2 == Type::TOP ) return Type::TOP;
486
487 // x/x == 1 since we always generate the dynamic divisor check for 0.
488 if( phase->eqv( in(1), in(2) ) )
489 return TypeInt::ONE;
490
491 // Either input is BOTTOM ==> the result is the local BOTTOM
492 const Type *bot = bottom_type();
493 if( (t1 == bot) || (t2 == bot) ||
494 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
495 return bot;
496
497 // Divide the two numbers. We approximate.
498 // If divisor is a constant and not zero
499 const TypeInt *i1 = t1->is_int();
500 const TypeInt *i2 = t2->is_int();
501 int widen = MAX2(i1->_widen, i2->_widen);
502
503 if( i2->is_con() && i2->get_con() != 0 ) {
504 int32 d = i2->get_con(); // Divisor
505 jint lo, hi;
506 if( d >= 0 ) {
507 lo = i1->_lo/d;
508 hi = i1->_hi/d;
509 } else {
510 if( d == -1 && i1->_lo == min_jint ) {
511 // 'min_jint/-1' throws arithmetic exception during compilation
512 lo = min_jint;
513 // do not support holes, 'hi' must go to either min_jint or max_jint:
514 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
515 hi = i1->_hi == min_jint ? min_jint : max_jint;
516 } else {
517 lo = i1->_hi/d;
518 hi = i1->_lo/d;
519 }
520 }
521 return TypeInt::make(lo, hi, widen);
522 }
523
524 // If the dividend is a constant
525 if( i1->is_con() ) {
526 int32 d = i1->get_con();
527 if( d < 0 ) {
528 if( d == min_jint ) {
529 // (-min_jint) == min_jint == (min_jint / -1)
530 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
531 } else {
532 return TypeInt::make(d, -d, widen);
533 }
534 }
535 return TypeInt::make(-d, d, widen);
536 }
537
538 // Otherwise we give up all hope
539 return TypeInt::INT;
540 }
541
542
543 //=============================================================================
544 //------------------------------Identity---------------------------------------
545 // If the divisor is 1, we are an identity on the dividend.
546 Node *DivLNode::Identity( PhaseTransform *phase ) {
547 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
548 }
549
550 //------------------------------Idealize---------------------------------------
551 // Dividing by a power of 2 is a shift.
552 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
553 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
554 // Don't bother trying to transform a dead node
555 if( in(0) && in(0)->is_top() ) return NULL;
556
557 const Type *t = phase->type( in(2) );
558 if( t == TypeLong::ONE ) // Identity?
559 return NULL; // Skip it
560
561 const TypeLong *tl = t->isa_long();
562 if( !tl ) return NULL;
563 if( !tl->is_con() ) return NULL;
564 jlong l = tl->get_con(); // Get divisor
565
566 if (l == 0) return NULL; // Dividing by zero constant does not idealize
567
568 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
569
570 // Dividing by MININT does not optimize as a power-of-2 shift.
571 if( l == min_jlong ) return NULL;
572
573 return transform_long_divide( phase, in(1), l );
574 }
575
576 //------------------------------Value------------------------------------------
577 // A DivLNode divides its inputs. The third input is a Control input, used to
578 // prevent hoisting the divide above an unsafe test.
579 const Type *DivLNode::Value( PhaseTransform *phase ) const {
580 // Either input is TOP ==> the result is TOP
581 const Type *t1 = phase->type( in(1) );
582 const Type *t2 = phase->type( in(2) );
583 if( t1 == Type::TOP ) return Type::TOP;
584 if( t2 == Type::TOP ) return Type::TOP;
585
586 // x/x == 1 since we always generate the dynamic divisor check for 0.
587 if( phase->eqv( in(1), in(2) ) )
588 return TypeLong::ONE;
589
590 // Either input is BOTTOM ==> the result is the local BOTTOM
591 const Type *bot = bottom_type();
592 if( (t1 == bot) || (t2 == bot) ||
593 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
594 return bot;
595
596 // Divide the two numbers. We approximate.
597 // If divisor is a constant and not zero
598 const TypeLong *i1 = t1->is_long();
599 const TypeLong *i2 = t2->is_long();
600 int widen = MAX2(i1->_widen, i2->_widen);
601
602 if( i2->is_con() && i2->get_con() != 0 ) {
603 jlong d = i2->get_con(); // Divisor
604 jlong lo, hi;
605 if( d >= 0 ) {
606 lo = i1->_lo/d;
607 hi = i1->_hi/d;
608 } else {
609 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
610 // 'min_jlong/-1' throws arithmetic exception during compilation
611 lo = min_jlong;
612 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
613 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
614 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
615 } else {
616 lo = i1->_hi/d;
617 hi = i1->_lo/d;
618 }
619 }
620 return TypeLong::make(lo, hi, widen);
621 }
622
623 // If the dividend is a constant
624 if( i1->is_con() ) {
625 jlong d = i1->get_con();
626 if( d < 0 ) {
627 if( d == min_jlong ) {
628 // (-min_jlong) == min_jlong == (min_jlong / -1)
629 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
630 } else {
631 return TypeLong::make(d, -d, widen);
632 }
633 }
634 return TypeLong::make(-d, d, widen);
635 }
636
637 // Otherwise we give up all hope
638 return TypeLong::LONG;
639 }
640
641
642 //=============================================================================
643 //------------------------------Value------------------------------------------
644 // An DivFNode divides its inputs. The third input is a Control input, used to
645 // prevent hoisting the divide above an unsafe test.
646 const Type *DivFNode::Value( PhaseTransform *phase ) const {
647 // Either input is TOP ==> the result is TOP
648 const Type *t1 = phase->type( in(1) );
649 const Type *t2 = phase->type( in(2) );
650 if( t1 == Type::TOP ) return Type::TOP;
651 if( t2 == Type::TOP ) return Type::TOP;
652
653 // Either input is BOTTOM ==> the result is the local BOTTOM
654 const Type *bot = bottom_type();
655 if( (t1 == bot) || (t2 == bot) ||
656 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
657 return bot;
658
659 // x/x == 1, we ignore 0/0.
660 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
661 // Does not work for variables because of NaN's
662 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
663 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
664 return TypeF::ONE;
665
666 if( t2 == TypeF::ONE )
667 return t1;
668
669 // If divisor is a constant and not zero, divide them numbers
670 if( t1->base() == Type::FloatCon &&
671 t2->base() == Type::FloatCon &&
672 t2->getf() != 0.0 ) // could be negative zero
673 return TypeF::make( t1->getf()/t2->getf() );
674
675 // If the dividend is a constant zero
676 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
677 // Test TypeF::ZERO is not sufficient as it could be negative zero
678
679 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
680 return TypeF::ZERO;
681
682 // Otherwise we give up all hope
683 return Type::FLOAT;
684 }
685
686 //------------------------------isA_Copy---------------------------------------
687 // Dividing by self is 1.
688 // If the divisor is 1, we are an identity on the dividend.
689 Node *DivFNode::Identity( PhaseTransform *phase ) {
690 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
691 }
692
693
694 //------------------------------Idealize---------------------------------------
695 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
696 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
697 // Don't bother trying to transform a dead node
698 if( in(0) && in(0)->is_top() ) return NULL;
699
700 const Type *t2 = phase->type( in(2) );
701 if( t2 == TypeF::ONE ) // Identity?
702 return NULL; // Skip it
703
704 const TypeF *tf = t2->isa_float_constant();
705 if( !tf ) return NULL;
706 if( tf->base() != Type::FloatCon ) return NULL;
707
708 // Check for out of range values
709 if( tf->is_nan() || !tf->is_finite() ) return NULL;
710
711 // Get the value
712 float f = tf->getf();
713 int exp;
714
715 // Only for special case of dividing by a power of 2
716 if( frexp((double)f, &exp) != 0.5 ) return NULL;
717
718 // Limit the range of acceptable exponents
719 if( exp < -126 || exp > 126 ) return NULL;
720
721 // Compute the reciprocal
722 float reciprocal = ((float)1.0) / f;
723
724 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
725
726 // return multiplication by the reciprocal
727 return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
728 }
729
730 //=============================================================================
731 //------------------------------Value------------------------------------------
732 // An DivDNode divides its inputs. The third input is a Control input, used to
733 // prevent hoisting the divide above an unsafe test.
734 const Type *DivDNode::Value( PhaseTransform *phase ) const {
735 // Either input is TOP ==> the result is TOP
736 const Type *t1 = phase->type( in(1) );
737 const Type *t2 = phase->type( in(2) );
738 if( t1 == Type::TOP ) return Type::TOP;
739 if( t2 == Type::TOP ) return Type::TOP;
740
741 // Either input is BOTTOM ==> the result is the local BOTTOM
742 const Type *bot = bottom_type();
743 if( (t1 == bot) || (t2 == bot) ||
744 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
745 return bot;
746
747 // x/x == 1, we ignore 0/0.
748 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
749 // Does not work for variables because of NaN's
750 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
751 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
752 return TypeD::ONE;
753
754 if( t2 == TypeD::ONE )
755 return t1;
756
757 #if defined(IA32)
758 if (!phase->C->method()->is_strict())
759 // Can't trust native compilers to properly fold strict double
760 // division with round-to-zero on this platform.
761 #endif
762 {
763 // If divisor is a constant and not zero, divide them numbers
764 if( t1->base() == Type::DoubleCon &&
765 t2->base() == Type::DoubleCon &&
766 t2->getd() != 0.0 ) // could be negative zero
767 return TypeD::make( t1->getd()/t2->getd() );
768 }
769
770 // If the dividend is a constant zero
771 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
772 // Test TypeF::ZERO is not sufficient as it could be negative zero
773 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
774 return TypeD::ZERO;
775
776 // Otherwise we give up all hope
777 return Type::DOUBLE;
778 }
779
780
781 //------------------------------isA_Copy---------------------------------------
782 // Dividing by self is 1.
783 // If the divisor is 1, we are an identity on the dividend.
784 Node *DivDNode::Identity( PhaseTransform *phase ) {
785 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
786 }
787
788 //------------------------------Idealize---------------------------------------
789 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
790 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
791 // Don't bother trying to transform a dead node
792 if( in(0) && in(0)->is_top() ) return NULL;
793
794 const Type *t2 = phase->type( in(2) );
795 if( t2 == TypeD::ONE ) // Identity?
796 return NULL; // Skip it
797
798 const TypeD *td = t2->isa_double_constant();
799 if( !td ) return NULL;
800 if( td->base() != Type::DoubleCon ) return NULL;
801
802 // Check for out of range values
803 if( td->is_nan() || !td->is_finite() ) return NULL;
804
805 // Get the value
806 double d = td->getd();
807 int exp;
808
809 // Only for special case of dividing by a power of 2
810 if( frexp(d, &exp) != 0.5 ) return NULL;
811
812 // Limit the range of acceptable exponents
813 if( exp < -1021 || exp > 1022 ) return NULL;
814
815 // Compute the reciprocal
816 double reciprocal = 1.0 / d;
817
818 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
819
820 // return multiplication by the reciprocal
821 return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
822 }
823
824 //=============================================================================
825 //------------------------------Idealize---------------------------------------
826 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
827 // Check for dead control input
828 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
829 // Don't bother trying to transform a dead node
830 if( in(0) && in(0)->is_top() ) return NULL;
831
832 // Get the modulus
833 const Type *t = phase->type( in(2) );
834 if( t == Type::TOP ) return NULL;
835 const TypeInt *ti = t->is_int();
836
837 // Check for useless control input
838 // Check for excluding mod-zero case
839 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
840 set_req(0, NULL); // Yank control input
841 return this;
842 }
843
844 // See if we are MOD'ing by 2^k or 2^k-1.
845 if( !ti->is_con() ) return NULL;
846 jint con = ti->get_con();
847
848 Node *hook = new (phase->C, 1) Node(1);
849
850 // First, special check for modulo 2^k-1
851 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
852 uint k = exact_log2(con+1); // Extract k
853
854 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
855 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*/};
856 int trip_count = 1;
857 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
858
859 // If the unroll factor is not too large, and if conditional moves are
860 // ok, then use this case
861 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
862 Node *x = in(1); // Value being mod'd
863 Node *divisor = in(2); // Also is mask
864
865 hook->init_req(0, x); // Add a use to x to prevent him from dying
866 // Generate code to reduce X rapidly to nearly 2^k-1.
867 for( int i = 0; i < trip_count; i++ ) {
868 Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) );
869 Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed
870 x = phase->transform( new (phase->C, 3) AddINode(xh,xl) );
871 hook->set_req(0, x);
872 }
873
874 // Generate sign-fixup code. Was original value positive?
875 // int hack_res = (i >= 0) ? divisor : 1;
876 Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) );
877 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
878 Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
879 // if( x >= hack_res ) x -= divisor;
880 Node *sub = phase->transform( new (phase->C, 3) SubINode( x, divisor ) );
881 Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) );
882 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
883 // Convention is to not transform the return value of an Ideal
884 // since Ideal is expected to return a modified 'this' or a new node.
885 Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT);
886 // cmov2 is now the mod
887
888 // Now remove the bogus extra edges used to keep things alive
889 if (can_reshape) {
890 phase->is_IterGVN()->remove_dead_node(hook);
891 } else {
892 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
893 }
894 return cmov2;
895 }
896 }
897
898 // Fell thru, the unroll case is not appropriate. Transform the modulo
899 // into a long multiply/int multiply/subtract case
900
901 // Cannot handle mod 0, and min_jint isn't handled by the transform
902 if( con == 0 || con == min_jint ) return NULL;
903
904 // Get the absolute value of the constant; at this point, we can use this
905 jint pos_con = (con >= 0) ? con : -con;
906
907 // integer Mod 1 is always 0
908 if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO);
909
910 int log2_con = -1;
911
912 // If this is a power of two, they maybe we can mask it
913 if( is_power_of_2(pos_con) ) {
914 log2_con = log2_intptr((intptr_t)pos_con);
915
916 const Type *dt = phase->type(in(1));
917 const TypeInt *dti = dt->isa_int();
918
919 // See if this can be masked, if the dividend is non-negative
920 if( dti && dti->_lo >= 0 )
921 return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) );
922 }
923
924 // Save in(1) so that it cannot be changed or deleted
925 hook->init_req(0, in(1));
926
927 // Divide using the transform from DivI to MulL
928 Node *result = transform_int_divide( phase, in(1), pos_con );
929 if (result != NULL) {
930 Node *divide = phase->transform(result);
931
932 // Re-multiply, using a shift if this is a power of two
933 Node *mult = NULL;
934
935 if( log2_con >= 0 )
936 mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) );
937 else
938 mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) );
939
940 // Finally, subtract the multiplied divided value from the original
941 result = new (phase->C, 3) SubINode( in(1), mult );
942 }
943
944 // Now remove the bogus extra edges used to keep things alive
945 if (can_reshape) {
946 phase->is_IterGVN()->remove_dead_node(hook);
947 } else {
948 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
949 }
950
951 // return the value
952 return result;
953 }
954
955 //------------------------------Value------------------------------------------
956 const Type *ModINode::Value( PhaseTransform *phase ) const {
957 // Either input is TOP ==> the result is TOP
958 const Type *t1 = phase->type( in(1) );
959 const Type *t2 = phase->type( in(2) );
960 if( t1 == Type::TOP ) return Type::TOP;
961 if( t2 == Type::TOP ) return Type::TOP;
962
963 // We always generate the dynamic check for 0.
964 // 0 MOD X is 0
965 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
966 // X MOD X is 0
967 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
968
969 // Either input is BOTTOM ==> the result is the local BOTTOM
970 const Type *bot = bottom_type();
971 if( (t1 == bot) || (t2 == bot) ||
972 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
973 return bot;
974
975 const TypeInt *i1 = t1->is_int();
976 const TypeInt *i2 = t2->is_int();
977 if( !i1->is_con() || !i2->is_con() ) {
978 if( i1->_lo >= 0 && i2->_lo >= 0 )
979 return TypeInt::POS;
980 // If both numbers are not constants, we know little.
981 return TypeInt::INT;
982 }
983 // Mod by zero? Throw exception at runtime!
984 if( !i2->get_con() ) return TypeInt::POS;
985
986 // We must be modulo'ing 2 float constants.
987 // Check for min_jint % '-1', result is defined to be '0'.
988 if( i1->get_con() == min_jint && i2->get_con() == -1 )
989 return TypeInt::ZERO;
990
991 return TypeInt::make( i1->get_con() % i2->get_con() );
992 }
993
994
995 //=============================================================================
996 //------------------------------Idealize---------------------------------------
997 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
998 // Check for dead control input
999 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
1000 // Don't bother trying to transform a dead node
1001 if( in(0) && in(0)->is_top() ) return NULL;
1002
1003 // Get the modulus
1004 const Type *t = phase->type( in(2) );
1005 if( t == Type::TOP ) return NULL;
1006 const TypeLong *tl = t->is_long();
1007
1008 // Check for useless control input
1009 // Check for excluding mod-zero case
1010 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
1011 set_req(0, NULL); // Yank control input
1012 return this;
1013 }
1014
1015 // See if we are MOD'ing by 2^k or 2^k-1.
1016 if( !tl->is_con() ) return NULL;
1017 jlong con = tl->get_con();
1018
1019 Node *hook = new (phase->C, 1) Node(1);
1020
1021 // Expand mod
1022 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
1023 uint k = exact_log2_long(con+1); // Extract k
1024
1025 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
1026 // Used to help a popular random number generator which does a long-mod
1027 // of 2^31-1 and shows up in SpecJBB and SciMark.
1028 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*/};
1029 int trip_count = 1;
1030 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
1031
1032 // If the unroll factor is not too large, and if conditional moves are
1033 // ok, then use this case
1034 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
1035 Node *x = in(1); // Value being mod'd
1036 Node *divisor = in(2); // Also is mask
1037
1038 hook->init_req(0, x); // Add a use to x to prevent him from dying
1039 // Generate code to reduce X rapidly to nearly 2^k-1.
1040 for( int i = 0; i < trip_count; i++ ) {
1041 Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) );
1042 Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed
1043 x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) );
1044 hook->set_req(0, x); // Add a use to x to prevent him from dying
1045 }
1046
1047 // Generate sign-fixup code. Was original value positive?
1048 // long hack_res = (i >= 0) ? divisor : CONST64(1);
1049 Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) );
1050 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
1051 Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
1052 // if( x >= hack_res ) x -= divisor;
1053 Node *sub = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) );
1054 Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) );
1055 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
1056 // Convention is to not transform the return value of an Ideal
1057 // since Ideal is expected to return a modified 'this' or a new node.
1058 Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG);
1059 // cmov2 is now the mod
1060
1061 // Now remove the bogus extra edges used to keep things alive
1062 if (can_reshape) {
1063 phase->is_IterGVN()->remove_dead_node(hook);
1064 } else {
1065 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1066 }
1067 return cmov2;
1068 }
1069 }
1070
1071 // Fell thru, the unroll case is not appropriate. Transform the modulo
1072 // into a long multiply/int multiply/subtract case
1073
1074 // Cannot handle mod 0, and min_jint isn't handled by the transform
1075 if( con == 0 || con == min_jlong ) return NULL;
1076
1077 // Get the absolute value of the constant; at this point, we can use this
1078 jlong pos_con = (con >= 0) ? con : -con;
1079
1080 // integer Mod 1 is always 0
1081 if( pos_con == 1 ) return new (phase->C, 1) ConLNode(TypeLong::ZERO);
1082
1083 int log2_con = -1;
1084
1085 // If this is a power of two, then maybe we can mask it
1086 if( is_power_of_2_long(pos_con) ) {
1087 log2_con = log2_long(pos_con);
1088
1089 const Type *dt = phase->type(in(1));
1090 const TypeLong *dtl = dt->isa_long();
1091
1092 // See if this can be masked, if the dividend is non-negative
1093 if( dtl && dtl->_lo >= 0 )
1094 return ( new (phase->C, 3) AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1095 }
1096
1097 // Save in(1) so that it cannot be changed or deleted
1098 hook->init_req(0, in(1));
1099
1100 // Divide using the transform from DivI to MulL
1101 Node *result = transform_long_divide( phase, in(1), pos_con );
1102 if (result != NULL) {
1103 Node *divide = phase->transform(result);
1104
1105 // Re-multiply, using a shift if this is a power of two
1106 Node *mult = NULL;
1107
1108 if( log2_con >= 0 )
1109 mult = phase->transform( new (phase->C, 3) LShiftLNode( divide, phase->intcon( log2_con ) ) );
1110 else
1111 mult = phase->transform( new (phase->C, 3) MulLNode( divide, phase->longcon( pos_con ) ) );
1112
1113 // Finally, subtract the multiplied divided value from the original
1114 result = new (phase->C, 3) SubLNode( in(1), mult );
1115 }
1116
1117 // Now remove the bogus extra edges used to keep things alive
1118 if (can_reshape) {
1119 phase->is_IterGVN()->remove_dead_node(hook);
1120 } else {
1121 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1122 }
1123
1124 // return the value
1125 return result;
1126 }
1127
1128 //------------------------------Value------------------------------------------
1129 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1130 // Either input is TOP ==> the result is TOP
1131 const Type *t1 = phase->type( in(1) );
1132 const Type *t2 = phase->type( in(2) );
1133 if( t1 == Type::TOP ) return Type::TOP;
1134 if( t2 == Type::TOP ) return Type::TOP;
1135
1136 // We always generate the dynamic check for 0.
1137 // 0 MOD X is 0
1138 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1139 // X MOD X is 0
1140 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1141
1142 // Either input is BOTTOM ==> the result is the local BOTTOM
1143 const Type *bot = bottom_type();
1144 if( (t1 == bot) || (t2 == bot) ||
1145 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1146 return bot;
1147
1148 const TypeLong *i1 = t1->is_long();
1149 const TypeLong *i2 = t2->is_long();
1150 if( !i1->is_con() || !i2->is_con() ) {
1151 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1152 return TypeLong::POS;
1153 // If both numbers are not constants, we know little.
1154 return TypeLong::LONG;
1155 }
1156 // Mod by zero? Throw exception at runtime!
1157 if( !i2->get_con() ) return TypeLong::POS;
1158
1159 // We must be modulo'ing 2 float constants.
1160 // Check for min_jint % '-1', result is defined to be '0'.
1161 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1162 return TypeLong::ZERO;
1163
1164 return TypeLong::make( i1->get_con() % i2->get_con() );
1165 }
1166
1167
1168 //=============================================================================
1169 //------------------------------Value------------------------------------------
1170 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1171 // Either input is TOP ==> the result is TOP
1172 const Type *t1 = phase->type( in(1) );
1173 const Type *t2 = phase->type( in(2) );
1174 if( t1 == Type::TOP ) return Type::TOP;
1175 if( t2 == Type::TOP ) return Type::TOP;
1176
1177 // Either input is BOTTOM ==> the result is the local BOTTOM
1178 const Type *bot = bottom_type();
1179 if( (t1 == bot) || (t2 == bot) ||
1180 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1181 return bot;
1182
1183 // If either number is not a constant, we know nothing.
1184 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1185 return Type::FLOAT; // note: x%x can be either NaN or 0
1186 }
1187
1188 float f1 = t1->getf();
1189 float f2 = t2->getf();
1190 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1191 jint x2 = jint_cast(f2);
1192
1193 // If either is a NaN, return an input NaN
1194 if (g_isnan(f1)) return t1;
1195 if (g_isnan(f2)) return t2;
1196
1197 // If an operand is infinity or the divisor is +/- zero, punt.
1198 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1199 return Type::FLOAT;
1200
1201 // We must be modulo'ing 2 float constants.
1202 // Make sure that the sign of the fmod is equal to the sign of the dividend
1203 jint xr = jint_cast(fmod(f1, f2));
1204 if ((x1 ^ xr) < 0) {
1205 xr ^= min_jint;
1206 }
1207
1208 return TypeF::make(jfloat_cast(xr));
1209 }
1210
1211
1212 //=============================================================================
1213 //------------------------------Value------------------------------------------
1214 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1215 // Either input is TOP ==> the result is TOP
1216 const Type *t1 = phase->type( in(1) );
1217 const Type *t2 = phase->type( in(2) );
1218 if( t1 == Type::TOP ) return Type::TOP;
1219 if( t2 == Type::TOP ) return Type::TOP;
1220
1221 // Either input is BOTTOM ==> the result is the local BOTTOM
1222 const Type *bot = bottom_type();
1223 if( (t1 == bot) || (t2 == bot) ||
1224 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1225 return bot;
1226
1227 // If either number is not a constant, we know nothing.
1228 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1229 return Type::DOUBLE; // note: x%x can be either NaN or 0
1230 }
1231
1232 double f1 = t1->getd();
1233 double f2 = t2->getd();
1234 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1235 jlong x2 = jlong_cast(f2);
1236
1237 // If either is a NaN, return an input NaN
1238 if (g_isnan(f1)) return t1;
1239 if (g_isnan(f2)) return t2;
1240
1241 // If an operand is infinity or the divisor is +/- zero, punt.
1242 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1243 return Type::DOUBLE;
1244
1245 // We must be modulo'ing 2 double constants.
1246 // Make sure that the sign of the fmod is equal to the sign of the dividend
1247 jlong xr = jlong_cast(fmod(f1, f2));
1248 if ((x1 ^ xr) < 0) {
1249 xr ^= min_jlong;
1250 }
1251
1252 return TypeD::make(jdouble_cast(xr));
1253 }
1254
1255 //=============================================================================
1256
1257 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1258 init_req(0, c);
1259 init_req(1, dividend);
1260 init_req(2, divisor);
1261 }
1262
1263 //------------------------------make------------------------------------------
1264 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
1265 Node* n = div_or_mod;
1266 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1267 "only div or mod input pattern accepted");
1268
1269 DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2));
1270 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1271 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1272 return divmod;
1273 }
1274
1275 //------------------------------make------------------------------------------
1276 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
1277 Node* n = div_or_mod;
1278 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1279 "only div or mod input pattern accepted");
1280
1281 DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2));
1282 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1283 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1284 return divmod;
1285 }
1286
1287 //------------------------------match------------------------------------------
1288 // return result(s) along with their RegMask info
1289 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1290 uint ideal_reg = proj->ideal_reg();
1291 RegMask rm;
1292 if (proj->_con == div_proj_num) {
1293 rm = match->divI_proj_mask();
1294 } else {
1295 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1296 rm = match->modI_proj_mask();
1297 }
1298 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1299 }
1300
1301
1302 //------------------------------match------------------------------------------
1303 // return result(s) along with their RegMask info
1304 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1305 uint ideal_reg = proj->ideal_reg();
1306 RegMask rm;
1307 if (proj->_con == div_proj_num) {
1308 rm = match->divL_proj_mask();
1309 } else {
1310 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1311 rm = match->modL_proj_mask();
1312 }
1313 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1314 }