Fri, 11 Jul 2008 01:14:44 -0700
Merge
1 /*
2 * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 // Portions of code courtesy of Clifford Click
27 // Optimization - Graph Style
29 #include "incls/_precompiled.incl"
30 #include "incls/_divnode.cpp.incl"
31 #include <math.h>
33 //----------------------magic_int_divide_constants-----------------------------
34 // Compute magic multiplier and shift constant for converting a 32 bit divide
35 // by constant into a multiply/shift/add series. Return false if calculations
36 // fail.
37 //
38 // Borrowed almost verbatum from Hacker's Delight by Henry S. Warren, Jr. with
39 // minor type name and parameter changes.
40 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
41 int32_t p;
42 uint32_t ad, anc, delta, q1, r1, q2, r2, t;
43 const uint32_t two31 = 0x80000000L; // 2**31.
45 ad = ABS(d);
46 if (d == 0 || d == 1) return false;
47 t = two31 + ((uint32_t)d >> 31);
48 anc = t - 1 - t%ad; // Absolute value of nc.
49 p = 31; // Init. p.
50 q1 = two31/anc; // Init. q1 = 2**p/|nc|.
51 r1 = two31 - q1*anc; // Init. r1 = rem(2**p, |nc|).
52 q2 = two31/ad; // Init. q2 = 2**p/|d|.
53 r2 = two31 - q2*ad; // Init. r2 = rem(2**p, |d|).
54 do {
55 p = p + 1;
56 q1 = 2*q1; // Update q1 = 2**p/|nc|.
57 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
58 if (r1 >= anc) { // (Must be an unsigned
59 q1 = q1 + 1; // comparison here).
60 r1 = r1 - anc;
61 }
62 q2 = 2*q2; // Update q2 = 2**p/|d|.
63 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
64 if (r2 >= ad) { // (Must be an unsigned
65 q2 = q2 + 1; // comparison here).
66 r2 = r2 - ad;
67 }
68 delta = ad - r2;
69 } while (q1 < delta || (q1 == delta && r1 == 0));
71 M = q2 + 1;
72 if (d < 0) M = -M; // Magic number and
73 s = p - 32; // shift amount to return.
75 return true;
76 }
78 //--------------------------transform_int_divide-------------------------------
79 // Convert a division by constant divisor into an alternate Ideal graph.
80 // Return NULL if no transformation occurs.
81 static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) {
83 // Check for invalid divisors
84 assert( divisor != 0 && divisor != min_jint,
85 "bad divisor for transforming to long multiply" );
87 bool d_pos = divisor >= 0;
88 jint d = d_pos ? divisor : -divisor;
89 const int N = 32;
91 // Result
92 Node *q = NULL;
94 if (d == 1) {
95 // division by +/- 1
96 if (!d_pos) {
97 // Just negate the value
98 q = new (phase->C, 3) SubINode(phase->intcon(0), dividend);
99 }
100 } else if ( is_power_of_2(d) ) {
101 // division by +/- a power of 2
103 // See if we can simply do a shift without rounding
104 bool needs_rounding = true;
105 const Type *dt = phase->type(dividend);
106 const TypeInt *dti = dt->isa_int();
107 if (dti && dti->_lo >= 0) {
108 // we don't need to round a positive dividend
109 needs_rounding = false;
110 } else if( dividend->Opcode() == Op_AndI ) {
111 // An AND mask of sufficient size clears the low bits and
112 // I can avoid rounding.
113 const TypeInt *andconi = phase->type( dividend->in(2) )->isa_int();
114 if( andconi && andconi->is_con(-d) ) {
115 dividend = dividend->in(1);
116 needs_rounding = false;
117 }
118 }
120 // Add rounding to the shift to handle the sign bit
121 int l = log2_intptr(d-1)+1;
122 if (needs_rounding) {
123 // Divide-by-power-of-2 can be made into a shift, but you have to do
124 // more math for the rounding. You need to add 0 for positive
125 // numbers, and "i-1" for negative numbers. Example: i=4, so the
126 // shift is by 2. You need to add 3 to negative dividends and 0 to
127 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
128 // (-2+3)>>2 becomes 0, etc.
130 // Compute 0 or -1, based on sign bit
131 Node *sign = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N - 1)));
132 // Mask sign bit to the low sign bits
133 Node *round = phase->transform(new (phase->C, 3) URShiftINode(sign, phase->intcon(N - l)));
134 // Round up before shifting
135 dividend = phase->transform(new (phase->C, 3) AddINode(dividend, round));
136 }
138 // Shift for division
139 q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l));
141 if (!d_pos) {
142 q = new (phase->C, 3) SubINode(phase->intcon(0), phase->transform(q));
143 }
144 } else {
145 // Attempt the jint constant divide -> multiply transform found in
146 // "Division by Invariant Integers using Multiplication"
147 // by Granlund and Montgomery
148 // See also "Hacker's Delight", chapter 10 by Warren.
150 jint magic_const;
151 jint shift_const;
152 if (magic_int_divide_constants(d, magic_const, shift_const)) {
153 Node *magic = phase->longcon(magic_const);
154 Node *dividend_long = phase->transform(new (phase->C, 2) ConvI2LNode(dividend));
156 // Compute the high half of the dividend x magic multiplication
157 Node *mul_hi = phase->transform(new (phase->C, 3) MulLNode(dividend_long, magic));
159 if (magic_const < 0) {
160 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N)));
161 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
163 // The magic multiplier is too large for a 32 bit constant. We've adjusted
164 // it down by 2^32, but have to add 1 dividend back in after the multiplication.
165 // This handles the "overflow" case described by Granlund and Montgomery.
166 mul_hi = phase->transform(new (phase->C, 3) AddINode(dividend, mul_hi));
168 // Shift over the (adjusted) mulhi
169 if (shift_const != 0) {
170 mul_hi = phase->transform(new (phase->C, 3) RShiftINode(mul_hi, phase->intcon(shift_const)));
171 }
172 } else {
173 // No add is required, we can merge the shifts together.
174 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
175 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
176 }
178 // Get a 0 or -1 from the sign of the dividend.
179 Node *addend0 = mul_hi;
180 Node *addend1 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1)));
182 // If the divisor is negative, swap the order of the input addends;
183 // this has the effect of negating the quotient.
184 if (!d_pos) {
185 Node *temp = addend0; addend0 = addend1; addend1 = temp;
186 }
188 // Adjust the final quotient by subtracting -1 (adding 1)
189 // from the mul_hi.
190 q = new (phase->C, 3) SubINode(addend0, addend1);
191 }
192 }
194 return q;
195 }
197 //---------------------magic_long_divide_constants-----------------------------
198 // Compute magic multiplier and shift constant for converting a 64 bit divide
199 // by constant into a multiply/shift/add series. Return false if calculations
200 // fail.
201 //
202 // Borrowed almost verbatum from Hacker's Delight by Henry S. Warren, Jr. with
203 // minor type name and parameter changes. Adjusted to 64 bit word width.
204 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) {
205 int64_t p;
206 uint64_t ad, anc, delta, q1, r1, q2, r2, t;
207 const uint64_t two63 = 0x8000000000000000LL; // 2**63.
209 ad = ABS(d);
210 if (d == 0 || d == 1) return false;
211 t = two63 + ((uint64_t)d >> 63);
212 anc = t - 1 - t%ad; // Absolute value of nc.
213 p = 63; // Init. p.
214 q1 = two63/anc; // Init. q1 = 2**p/|nc|.
215 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|).
216 q2 = two63/ad; // Init. q2 = 2**p/|d|.
217 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|).
218 do {
219 p = p + 1;
220 q1 = 2*q1; // Update q1 = 2**p/|nc|.
221 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
222 if (r1 >= anc) { // (Must be an unsigned
223 q1 = q1 + 1; // comparison here).
224 r1 = r1 - anc;
225 }
226 q2 = 2*q2; // Update q2 = 2**p/|d|.
227 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
228 if (r2 >= ad) { // (Must be an unsigned
229 q2 = q2 + 1; // comparison here).
230 r2 = r2 - ad;
231 }
232 delta = ad - r2;
233 } while (q1 < delta || (q1 == delta && r1 == 0));
235 M = q2 + 1;
236 if (d < 0) M = -M; // Magic number and
237 s = p - 64; // shift amount to return.
239 return true;
240 }
242 //---------------------long_by_long_mulhi--------------------------------------
243 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication
244 static Node *long_by_long_mulhi( PhaseGVN *phase, Node *dividend, jlong magic_const) {
245 // If the architecture supports a 64x64 mulhi, there is
246 // no need to synthesize it in ideal nodes.
247 if (Matcher::has_match_rule(Op_MulHiL)) {
248 Node *v = phase->longcon(magic_const);
249 return new (phase->C, 3) MulHiLNode(dividend, v);
250 }
252 const int N = 64;
254 Node *u_hi = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2)));
255 Node *u_lo = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
257 Node *v_hi = phase->longcon(magic_const >> N/2);
258 Node *v_lo = phase->longcon(magic_const & 0XFFFFFFFF);
260 Node *hihi_product = phase->transform(new (phase->C, 3) MulLNode(u_hi, v_hi));
261 Node *hilo_product = phase->transform(new (phase->C, 3) MulLNode(u_hi, v_lo));
262 Node *lohi_product = phase->transform(new (phase->C, 3) MulLNode(u_lo, v_hi));
263 Node *lolo_product = phase->transform(new (phase->C, 3) MulLNode(u_lo, v_lo));
265 Node *t1 = phase->transform(new (phase->C, 3) URShiftLNode(lolo_product, phase->intcon(N / 2)));
266 Node *t2 = phase->transform(new (phase->C, 3) AddLNode(hilo_product, t1));
267 Node *t3 = phase->transform(new (phase->C, 3) RShiftLNode(t2, phase->intcon(N / 2)));
268 Node *t4 = phase->transform(new (phase->C, 3) AndLNode(t2, phase->longcon(0xFFFFFFFF)));
269 Node *t5 = phase->transform(new (phase->C, 3) AddLNode(t4, lohi_product));
270 Node *t6 = phase->transform(new (phase->C, 3) RShiftLNode(t5, phase->intcon(N / 2)));
271 Node *t7 = phase->transform(new (phase->C, 3) AddLNode(t3, hihi_product));
273 return new (phase->C, 3) AddLNode(t7, t6);
274 }
277 //--------------------------transform_long_divide------------------------------
278 // Convert a division by constant divisor into an alternate Ideal graph.
279 // Return NULL if no transformation occurs.
280 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
281 // Check for invalid divisors
282 assert( divisor != 0L && divisor != min_jlong,
283 "bad divisor for transforming to long multiply" );
285 bool d_pos = divisor >= 0;
286 jlong d = d_pos ? divisor : -divisor;
287 const int N = 64;
289 // Result
290 Node *q = NULL;
292 if (d == 1) {
293 // division by +/- 1
294 if (!d_pos) {
295 // Just negate the value
296 q = new (phase->C, 3) SubLNode(phase->longcon(0), dividend);
297 }
298 } else if ( is_power_of_2_long(d) ) {
300 // division by +/- a power of 2
302 // See if we can simply do a shift without rounding
303 bool needs_rounding = true;
304 const Type *dt = phase->type(dividend);
305 const TypeLong *dtl = dt->isa_long();
307 if (dtl && dtl->_lo > 0) {
308 // we don't need to round a positive dividend
309 needs_rounding = false;
310 } else if( dividend->Opcode() == Op_AndL ) {
311 // An AND mask of sufficient size clears the low bits and
312 // I can avoid rounding.
313 const TypeLong *andconl = phase->type( dividend->in(2) )->isa_long();
314 if( andconl && andconl->is_con(-d)) {
315 dividend = dividend->in(1);
316 needs_rounding = false;
317 }
318 }
320 // Add rounding to the shift to handle the sign bit
321 int l = log2_long(d-1)+1;
322 if (needs_rounding) {
323 // Divide-by-power-of-2 can be made into a shift, but you have to do
324 // more math for the rounding. You need to add 0 for positive
325 // numbers, and "i-1" for negative numbers. Example: i=4, so the
326 // shift is by 2. You need to add 3 to negative dividends and 0 to
327 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
328 // (-2+3)>>2 becomes 0, etc.
330 // Compute 0 or -1, based on sign bit
331 Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N - 1)));
332 // Mask sign bit to the low sign bits
333 Node *round = phase->transform(new (phase->C, 3) URShiftLNode(sign, phase->intcon(N - l)));
334 // Round up before shifting
335 dividend = phase->transform(new (phase->C, 3) AddLNode(dividend, round));
336 }
338 // Shift for division
339 q = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(l));
341 if (!d_pos) {
342 q = new (phase->C, 3) SubLNode(phase->longcon(0), phase->transform(q));
343 }
344 } else {
345 // Attempt the jlong constant divide -> multiply transform found in
346 // "Division by Invariant Integers using Multiplication"
347 // by Granlund and Montgomery
348 // See also "Hacker's Delight", chapter 10 by Warren.
350 jlong magic_const;
351 jint shift_const;
352 if (magic_long_divide_constants(d, magic_const, shift_const)) {
353 // Compute the high half of the dividend x magic multiplication
354 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
356 // The high half of the 128-bit multiply is computed.
357 if (magic_const < 0) {
358 // The magic multiplier is too large for a 64 bit constant. We've adjusted
359 // it down by 2^64, but have to add 1 dividend back in after the multiplication.
360 // This handles the "overflow" case described by Granlund and Montgomery.
361 mul_hi = phase->transform(new (phase->C, 3) AddLNode(dividend, mul_hi));
362 }
364 // Shift over the (adjusted) mulhi
365 if (shift_const != 0) {
366 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(shift_const)));
367 }
369 // Get a 0 or -1 from the sign of the dividend.
370 Node *addend0 = mul_hi;
371 Node *addend1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N-1)));
373 // If the divisor is negative, swap the order of the input addends;
374 // this has the effect of negating the quotient.
375 if (!d_pos) {
376 Node *temp = addend0; addend0 = addend1; addend1 = temp;
377 }
379 // Adjust the final quotient by subtracting -1 (adding 1)
380 // from the mul_hi.
381 q = new (phase->C, 3) SubLNode(addend0, addend1);
382 }
383 }
385 return q;
386 }
388 //=============================================================================
389 //------------------------------Identity---------------------------------------
390 // If the divisor is 1, we are an identity on the dividend.
391 Node *DivINode::Identity( PhaseTransform *phase ) {
392 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
393 }
395 //------------------------------Idealize---------------------------------------
396 // Divides can be changed to multiplies and/or shifts
397 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
398 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
400 const Type *t = phase->type( in(2) );
401 if( t == TypeInt::ONE ) // Identity?
402 return NULL; // Skip it
404 const TypeInt *ti = t->isa_int();
405 if( !ti ) return NULL;
406 if( !ti->is_con() ) return NULL;
407 jint i = ti->get_con(); // Get divisor
409 if (i == 0) return NULL; // Dividing by zero constant does not idealize
411 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
413 // Dividing by MININT does not optimize as a power-of-2 shift.
414 if( i == min_jint ) return NULL;
416 return transform_int_divide( phase, in(1), i );
417 }
419 //------------------------------Value------------------------------------------
420 // A DivINode divides its inputs. The third input is a Control input, used to
421 // prevent hoisting the divide above an unsafe test.
422 const Type *DivINode::Value( PhaseTransform *phase ) const {
423 // Either input is TOP ==> the result is TOP
424 const Type *t1 = phase->type( in(1) );
425 const Type *t2 = phase->type( in(2) );
426 if( t1 == Type::TOP ) return Type::TOP;
427 if( t2 == Type::TOP ) return Type::TOP;
429 // x/x == 1 since we always generate the dynamic divisor check for 0.
430 if( phase->eqv( in(1), in(2) ) )
431 return TypeInt::ONE;
433 // Either input is BOTTOM ==> the result is the local BOTTOM
434 const Type *bot = bottom_type();
435 if( (t1 == bot) || (t2 == bot) ||
436 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
437 return bot;
439 // Divide the two numbers. We approximate.
440 // If divisor is a constant and not zero
441 const TypeInt *i1 = t1->is_int();
442 const TypeInt *i2 = t2->is_int();
443 int widen = MAX2(i1->_widen, i2->_widen);
445 if( i2->is_con() && i2->get_con() != 0 ) {
446 int32 d = i2->get_con(); // Divisor
447 jint lo, hi;
448 if( d >= 0 ) {
449 lo = i1->_lo/d;
450 hi = i1->_hi/d;
451 } else {
452 if( d == -1 && i1->_lo == min_jint ) {
453 // 'min_jint/-1' throws arithmetic exception during compilation
454 lo = min_jint;
455 // do not support holes, 'hi' must go to either min_jint or max_jint:
456 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
457 hi = i1->_hi == min_jint ? min_jint : max_jint;
458 } else {
459 lo = i1->_hi/d;
460 hi = i1->_lo/d;
461 }
462 }
463 return TypeInt::make(lo, hi, widen);
464 }
466 // If the dividend is a constant
467 if( i1->is_con() ) {
468 int32 d = i1->get_con();
469 if( d < 0 ) {
470 if( d == min_jint ) {
471 // (-min_jint) == min_jint == (min_jint / -1)
472 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
473 } else {
474 return TypeInt::make(d, -d, widen);
475 }
476 }
477 return TypeInt::make(-d, d, widen);
478 }
480 // Otherwise we give up all hope
481 return TypeInt::INT;
482 }
485 //=============================================================================
486 //------------------------------Identity---------------------------------------
487 // If the divisor is 1, we are an identity on the dividend.
488 Node *DivLNode::Identity( PhaseTransform *phase ) {
489 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
490 }
492 //------------------------------Idealize---------------------------------------
493 // Dividing by a power of 2 is a shift.
494 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
495 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
497 const Type *t = phase->type( in(2) );
498 if( t == TypeLong::ONE ) // Identity?
499 return NULL; // Skip it
501 const TypeLong *tl = t->isa_long();
502 if( !tl ) return NULL;
503 if( !tl->is_con() ) return NULL;
504 jlong l = tl->get_con(); // Get divisor
506 if (l == 0) return NULL; // Dividing by zero constant does not idealize
508 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
510 // Dividing by MININT does not optimize as a power-of-2 shift.
511 if( l == min_jlong ) return NULL;
513 return transform_long_divide( phase, in(1), l );
514 }
516 //------------------------------Value------------------------------------------
517 // A DivLNode divides its inputs. The third input is a Control input, used to
518 // prevent hoisting the divide above an unsafe test.
519 const Type *DivLNode::Value( PhaseTransform *phase ) const {
520 // Either input is TOP ==> the result is TOP
521 const Type *t1 = phase->type( in(1) );
522 const Type *t2 = phase->type( in(2) );
523 if( t1 == Type::TOP ) return Type::TOP;
524 if( t2 == Type::TOP ) return Type::TOP;
526 // x/x == 1 since we always generate the dynamic divisor check for 0.
527 if( phase->eqv( in(1), in(2) ) )
528 return TypeLong::ONE;
530 // Either input is BOTTOM ==> the result is the local BOTTOM
531 const Type *bot = bottom_type();
532 if( (t1 == bot) || (t2 == bot) ||
533 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
534 return bot;
536 // Divide the two numbers. We approximate.
537 // If divisor is a constant and not zero
538 const TypeLong *i1 = t1->is_long();
539 const TypeLong *i2 = t2->is_long();
540 int widen = MAX2(i1->_widen, i2->_widen);
542 if( i2->is_con() && i2->get_con() != 0 ) {
543 jlong d = i2->get_con(); // Divisor
544 jlong lo, hi;
545 if( d >= 0 ) {
546 lo = i1->_lo/d;
547 hi = i1->_hi/d;
548 } else {
549 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
550 // 'min_jlong/-1' throws arithmetic exception during compilation
551 lo = min_jlong;
552 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
553 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
554 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
555 } else {
556 lo = i1->_hi/d;
557 hi = i1->_lo/d;
558 }
559 }
560 return TypeLong::make(lo, hi, widen);
561 }
563 // If the dividend is a constant
564 if( i1->is_con() ) {
565 jlong d = i1->get_con();
566 if( d < 0 ) {
567 if( d == min_jlong ) {
568 // (-min_jlong) == min_jlong == (min_jlong / -1)
569 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
570 } else {
571 return TypeLong::make(d, -d, widen);
572 }
573 }
574 return TypeLong::make(-d, d, widen);
575 }
577 // Otherwise we give up all hope
578 return TypeLong::LONG;
579 }
582 //=============================================================================
583 //------------------------------Value------------------------------------------
584 // An DivFNode divides its inputs. The third input is a Control input, used to
585 // prevent hoisting the divide above an unsafe test.
586 const Type *DivFNode::Value( PhaseTransform *phase ) const {
587 // Either input is TOP ==> the result is TOP
588 const Type *t1 = phase->type( in(1) );
589 const Type *t2 = phase->type( in(2) );
590 if( t1 == Type::TOP ) return Type::TOP;
591 if( t2 == Type::TOP ) return Type::TOP;
593 // Either input is BOTTOM ==> the result is the local BOTTOM
594 const Type *bot = bottom_type();
595 if( (t1 == bot) || (t2 == bot) ||
596 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
597 return bot;
599 // x/x == 1, we ignore 0/0.
600 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
601 // Does not work for variables because of NaN's
602 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
603 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
604 return TypeF::ONE;
606 if( t2 == TypeF::ONE )
607 return t1;
609 // If divisor is a constant and not zero, divide them numbers
610 if( t1->base() == Type::FloatCon &&
611 t2->base() == Type::FloatCon &&
612 t2->getf() != 0.0 ) // could be negative zero
613 return TypeF::make( t1->getf()/t2->getf() );
615 // If the dividend is a constant zero
616 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
617 // Test TypeF::ZERO is not sufficient as it could be negative zero
619 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
620 return TypeF::ZERO;
622 // Otherwise we give up all hope
623 return Type::FLOAT;
624 }
626 //------------------------------isA_Copy---------------------------------------
627 // Dividing by self is 1.
628 // If the divisor is 1, we are an identity on the dividend.
629 Node *DivFNode::Identity( PhaseTransform *phase ) {
630 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
631 }
634 //------------------------------Idealize---------------------------------------
635 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
636 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
638 const Type *t2 = phase->type( in(2) );
639 if( t2 == TypeF::ONE ) // Identity?
640 return NULL; // Skip it
642 const TypeF *tf = t2->isa_float_constant();
643 if( !tf ) return NULL;
644 if( tf->base() != Type::FloatCon ) return NULL;
646 // Check for out of range values
647 if( tf->is_nan() || !tf->is_finite() ) return NULL;
649 // Get the value
650 float f = tf->getf();
651 int exp;
653 // Only for special case of dividing by a power of 2
654 if( frexp((double)f, &exp) != 0.5 ) return NULL;
656 // Limit the range of acceptable exponents
657 if( exp < -126 || exp > 126 ) return NULL;
659 // Compute the reciprocal
660 float reciprocal = ((float)1.0) / f;
662 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
664 // return multiplication by the reciprocal
665 return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
666 }
668 //=============================================================================
669 //------------------------------Value------------------------------------------
670 // An DivDNode divides its inputs. The third input is a Control input, used to
671 // prevent hoisting the divide above an unsafe test.
672 const Type *DivDNode::Value( PhaseTransform *phase ) const {
673 // Either input is TOP ==> the result is TOP
674 const Type *t1 = phase->type( in(1) );
675 const Type *t2 = phase->type( in(2) );
676 if( t1 == Type::TOP ) return Type::TOP;
677 if( t2 == Type::TOP ) return Type::TOP;
679 // Either input is BOTTOM ==> the result is the local BOTTOM
680 const Type *bot = bottom_type();
681 if( (t1 == bot) || (t2 == bot) ||
682 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
683 return bot;
685 // x/x == 1, we ignore 0/0.
686 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
687 // Does not work for variables because of NaN's
688 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
689 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
690 return TypeD::ONE;
692 if( t2 == TypeD::ONE )
693 return t1;
695 // If divisor is a constant and not zero, divide them numbers
696 if( t1->base() == Type::DoubleCon &&
697 t2->base() == Type::DoubleCon &&
698 t2->getd() != 0.0 ) // could be negative zero
699 return TypeD::make( t1->getd()/t2->getd() );
701 // If the dividend is a constant zero
702 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
703 // Test TypeF::ZERO is not sufficient as it could be negative zero
704 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
705 return TypeD::ZERO;
707 // Otherwise we give up all hope
708 return Type::DOUBLE;
709 }
712 //------------------------------isA_Copy---------------------------------------
713 // Dividing by self is 1.
714 // If the divisor is 1, we are an identity on the dividend.
715 Node *DivDNode::Identity( PhaseTransform *phase ) {
716 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
717 }
719 //------------------------------Idealize---------------------------------------
720 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
721 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
723 const Type *t2 = phase->type( in(2) );
724 if( t2 == TypeD::ONE ) // Identity?
725 return NULL; // Skip it
727 const TypeD *td = t2->isa_double_constant();
728 if( !td ) return NULL;
729 if( td->base() != Type::DoubleCon ) return NULL;
731 // Check for out of range values
732 if( td->is_nan() || !td->is_finite() ) return NULL;
734 // Get the value
735 double d = td->getd();
736 int exp;
738 // Only for special case of dividing by a power of 2
739 if( frexp(d, &exp) != 0.5 ) return NULL;
741 // Limit the range of acceptable exponents
742 if( exp < -1021 || exp > 1022 ) return NULL;
744 // Compute the reciprocal
745 double reciprocal = 1.0 / d;
747 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
749 // return multiplication by the reciprocal
750 return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
751 }
753 //=============================================================================
754 //------------------------------Idealize---------------------------------------
755 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
756 // Check for dead control input
757 if( remove_dead_region(phase, can_reshape) ) return this;
759 // Get the modulus
760 const Type *t = phase->type( in(2) );
761 if( t == Type::TOP ) return NULL;
762 const TypeInt *ti = t->is_int();
764 // Check for useless control input
765 // Check for excluding mod-zero case
766 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
767 set_req(0, NULL); // Yank control input
768 return this;
769 }
771 // See if we are MOD'ing by 2^k or 2^k-1.
772 if( !ti->is_con() ) return NULL;
773 jint con = ti->get_con();
775 Node *hook = new (phase->C, 1) Node(1);
777 // First, special check for modulo 2^k-1
778 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
779 uint k = exact_log2(con+1); // Extract k
781 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
782 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*/};
783 int trip_count = 1;
784 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
786 // If the unroll factor is not too large, and if conditional moves are
787 // ok, then use this case
788 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
789 Node *x = in(1); // Value being mod'd
790 Node *divisor = in(2); // Also is mask
792 hook->init_req(0, x); // Add a use to x to prevent him from dying
793 // Generate code to reduce X rapidly to nearly 2^k-1.
794 for( int i = 0; i < trip_count; i++ ) {
795 Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) );
796 Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed
797 x = phase->transform( new (phase->C, 3) AddINode(xh,xl) );
798 hook->set_req(0, x);
799 }
801 // Generate sign-fixup code. Was original value positive?
802 // int hack_res = (i >= 0) ? divisor : 1;
803 Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) );
804 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
805 Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
806 // if( x >= hack_res ) x -= divisor;
807 Node *sub = phase->transform( new (phase->C, 3) SubINode( x, divisor ) );
808 Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) );
809 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
810 // Convention is to not transform the return value of an Ideal
811 // since Ideal is expected to return a modified 'this' or a new node.
812 Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT);
813 // cmov2 is now the mod
815 // Now remove the bogus extra edges used to keep things alive
816 if (can_reshape) {
817 phase->is_IterGVN()->remove_dead_node(hook);
818 } else {
819 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
820 }
821 return cmov2;
822 }
823 }
825 // Fell thru, the unroll case is not appropriate. Transform the modulo
826 // into a long multiply/int multiply/subtract case
828 // Cannot handle mod 0, and min_jint isn't handled by the transform
829 if( con == 0 || con == min_jint ) return NULL;
831 // Get the absolute value of the constant; at this point, we can use this
832 jint pos_con = (con >= 0) ? con : -con;
834 // integer Mod 1 is always 0
835 if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO);
837 int log2_con = -1;
839 // If this is a power of two, they maybe we can mask it
840 if( is_power_of_2(pos_con) ) {
841 log2_con = log2_intptr((intptr_t)pos_con);
843 const Type *dt = phase->type(in(1));
844 const TypeInt *dti = dt->isa_int();
846 // See if this can be masked, if the dividend is non-negative
847 if( dti && dti->_lo >= 0 )
848 return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) );
849 }
851 // Save in(1) so that it cannot be changed or deleted
852 hook->init_req(0, in(1));
854 // Divide using the transform from DivI to MulL
855 Node *result = transform_int_divide( phase, in(1), pos_con );
856 if (result != NULL) {
857 Node *divide = phase->transform(result);
859 // Re-multiply, using a shift if this is a power of two
860 Node *mult = NULL;
862 if( log2_con >= 0 )
863 mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) );
864 else
865 mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) );
867 // Finally, subtract the multiplied divided value from the original
868 result = new (phase->C, 3) SubINode( in(1), mult );
869 }
871 // Now remove the bogus extra edges used to keep things alive
872 if (can_reshape) {
873 phase->is_IterGVN()->remove_dead_node(hook);
874 } else {
875 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
876 }
878 // return the value
879 return result;
880 }
882 //------------------------------Value------------------------------------------
883 const Type *ModINode::Value( PhaseTransform *phase ) const {
884 // Either input is TOP ==> the result is TOP
885 const Type *t1 = phase->type( in(1) );
886 const Type *t2 = phase->type( in(2) );
887 if( t1 == Type::TOP ) return Type::TOP;
888 if( t2 == Type::TOP ) return Type::TOP;
890 // We always generate the dynamic check for 0.
891 // 0 MOD X is 0
892 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
893 // X MOD X is 0
894 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
896 // Either input is BOTTOM ==> the result is the local BOTTOM
897 const Type *bot = bottom_type();
898 if( (t1 == bot) || (t2 == bot) ||
899 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
900 return bot;
902 const TypeInt *i1 = t1->is_int();
903 const TypeInt *i2 = t2->is_int();
904 if( !i1->is_con() || !i2->is_con() ) {
905 if( i1->_lo >= 0 && i2->_lo >= 0 )
906 return TypeInt::POS;
907 // If both numbers are not constants, we know little.
908 return TypeInt::INT;
909 }
910 // Mod by zero? Throw exception at runtime!
911 if( !i2->get_con() ) return TypeInt::POS;
913 // We must be modulo'ing 2 float constants.
914 // Check for min_jint % '-1', result is defined to be '0'.
915 if( i1->get_con() == min_jint && i2->get_con() == -1 )
916 return TypeInt::ZERO;
918 return TypeInt::make( i1->get_con() % i2->get_con() );
919 }
922 //=============================================================================
923 //------------------------------Idealize---------------------------------------
924 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
925 // Check for dead control input
926 if( remove_dead_region(phase, can_reshape) ) return this;
928 // Get the modulus
929 const Type *t = phase->type( in(2) );
930 if( t == Type::TOP ) return NULL;
931 const TypeLong *tl = t->is_long();
933 // Check for useless control input
934 // Check for excluding mod-zero case
935 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
936 set_req(0, NULL); // Yank control input
937 return this;
938 }
940 // See if we are MOD'ing by 2^k or 2^k-1.
941 if( !tl->is_con() ) return NULL;
942 jlong con = tl->get_con();
944 Node *hook = new (phase->C, 1) Node(1);
946 // Expand mod
947 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
948 uint k = log2_long(con); // Extract k
950 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
951 // Used to help a popular random number generator which does a long-mod
952 // of 2^31-1 and shows up in SpecJBB and SciMark.
953 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*/};
954 int trip_count = 1;
955 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
957 // If the unroll factor is not too large, and if conditional moves are
958 // ok, then use this case
959 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
960 Node *x = in(1); // Value being mod'd
961 Node *divisor = in(2); // Also is mask
963 hook->init_req(0, x); // Add a use to x to prevent him from dying
964 // Generate code to reduce X rapidly to nearly 2^k-1.
965 for( int i = 0; i < trip_count; i++ ) {
966 Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) );
967 Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed
968 x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) );
969 hook->set_req(0, x); // Add a use to x to prevent him from dying
970 }
972 // Generate sign-fixup code. Was original value positive?
973 // long hack_res = (i >= 0) ? divisor : CONST64(1);
974 Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) );
975 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
976 Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
977 // if( x >= hack_res ) x -= divisor;
978 Node *sub = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) );
979 Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) );
980 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
981 // Convention is to not transform the return value of an Ideal
982 // since Ideal is expected to return a modified 'this' or a new node.
983 Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG);
984 // cmov2 is now the mod
986 // Now remove the bogus extra edges used to keep things alive
987 if (can_reshape) {
988 phase->is_IterGVN()->remove_dead_node(hook);
989 } else {
990 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
991 }
992 return cmov2;
993 }
994 }
996 // Fell thru, the unroll case is not appropriate. Transform the modulo
997 // into a long multiply/int multiply/subtract case
999 // Cannot handle mod 0, and min_jint isn't handled by the transform
1000 if( con == 0 || con == min_jlong ) return NULL;
1002 // Get the absolute value of the constant; at this point, we can use this
1003 jlong pos_con = (con >= 0) ? con : -con;
1005 // integer Mod 1 is always 0
1006 if( pos_con == 1 ) return new (phase->C, 1) ConLNode(TypeLong::ZERO);
1008 int log2_con = -1;
1010 // If this is a power of two, they maybe we can mask it
1011 if( is_power_of_2_long(pos_con) ) {
1012 log2_con = log2_long(pos_con);
1014 const Type *dt = phase->type(in(1));
1015 const TypeLong *dtl = dt->isa_long();
1017 // See if this can be masked, if the dividend is non-negative
1018 if( dtl && dtl->_lo >= 0 )
1019 return ( new (phase->C, 3) AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1020 }
1022 // Save in(1) so that it cannot be changed or deleted
1023 hook->init_req(0, in(1));
1025 // Divide using the transform from DivI to MulL
1026 Node *result = transform_long_divide( phase, in(1), pos_con );
1027 if (result != NULL) {
1028 Node *divide = phase->transform(result);
1030 // Re-multiply, using a shift if this is a power of two
1031 Node *mult = NULL;
1033 if( log2_con >= 0 )
1034 mult = phase->transform( new (phase->C, 3) LShiftLNode( divide, phase->intcon( log2_con ) ) );
1035 else
1036 mult = phase->transform( new (phase->C, 3) MulLNode( divide, phase->longcon( pos_con ) ) );
1038 // Finally, subtract the multiplied divided value from the original
1039 result = new (phase->C, 3) SubLNode( in(1), mult );
1040 }
1042 // Now remove the bogus extra edges used to keep things alive
1043 if (can_reshape) {
1044 phase->is_IterGVN()->remove_dead_node(hook);
1045 } else {
1046 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1047 }
1049 // return the value
1050 return result;
1051 }
1053 //------------------------------Value------------------------------------------
1054 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1055 // Either input is TOP ==> the result is TOP
1056 const Type *t1 = phase->type( in(1) );
1057 const Type *t2 = phase->type( in(2) );
1058 if( t1 == Type::TOP ) return Type::TOP;
1059 if( t2 == Type::TOP ) return Type::TOP;
1061 // We always generate the dynamic check for 0.
1062 // 0 MOD X is 0
1063 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1064 // X MOD X is 0
1065 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1067 // Either input is BOTTOM ==> the result is the local BOTTOM
1068 const Type *bot = bottom_type();
1069 if( (t1 == bot) || (t2 == bot) ||
1070 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1071 return bot;
1073 const TypeLong *i1 = t1->is_long();
1074 const TypeLong *i2 = t2->is_long();
1075 if( !i1->is_con() || !i2->is_con() ) {
1076 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1077 return TypeLong::POS;
1078 // If both numbers are not constants, we know little.
1079 return TypeLong::LONG;
1080 }
1081 // Mod by zero? Throw exception at runtime!
1082 if( !i2->get_con() ) return TypeLong::POS;
1084 // We must be modulo'ing 2 float constants.
1085 // Check for min_jint % '-1', result is defined to be '0'.
1086 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1087 return TypeLong::ZERO;
1089 return TypeLong::make( i1->get_con() % i2->get_con() );
1090 }
1093 //=============================================================================
1094 //------------------------------Value------------------------------------------
1095 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1096 // Either input is TOP ==> the result is TOP
1097 const Type *t1 = phase->type( in(1) );
1098 const Type *t2 = phase->type( in(2) );
1099 if( t1 == Type::TOP ) return Type::TOP;
1100 if( t2 == Type::TOP ) return Type::TOP;
1102 // Either input is BOTTOM ==> the result is the local BOTTOM
1103 const Type *bot = bottom_type();
1104 if( (t1 == bot) || (t2 == bot) ||
1105 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1106 return bot;
1108 // If either number is not a constant, we know nothing.
1109 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1110 return Type::FLOAT; // note: x%x can be either NaN or 0
1111 }
1113 float f1 = t1->getf();
1114 float f2 = t2->getf();
1115 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1116 jint x2 = jint_cast(f2);
1118 // If either is a NaN, return an input NaN
1119 if (g_isnan(f1)) return t1;
1120 if (g_isnan(f2)) return t2;
1122 // If an operand is infinity or the divisor is +/- zero, punt.
1123 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1124 return Type::FLOAT;
1126 // We must be modulo'ing 2 float constants.
1127 // Make sure that the sign of the fmod is equal to the sign of the dividend
1128 jint xr = jint_cast(fmod(f1, f2));
1129 if ((x1 ^ xr) < 0) {
1130 xr ^= min_jint;
1131 }
1133 return TypeF::make(jfloat_cast(xr));
1134 }
1137 //=============================================================================
1138 //------------------------------Value------------------------------------------
1139 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1140 // Either input is TOP ==> the result is TOP
1141 const Type *t1 = phase->type( in(1) );
1142 const Type *t2 = phase->type( in(2) );
1143 if( t1 == Type::TOP ) return Type::TOP;
1144 if( t2 == Type::TOP ) return Type::TOP;
1146 // Either input is BOTTOM ==> the result is the local BOTTOM
1147 const Type *bot = bottom_type();
1148 if( (t1 == bot) || (t2 == bot) ||
1149 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1150 return bot;
1152 // If either number is not a constant, we know nothing.
1153 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1154 return Type::DOUBLE; // note: x%x can be either NaN or 0
1155 }
1157 double f1 = t1->getd();
1158 double f2 = t2->getd();
1159 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1160 jlong x2 = jlong_cast(f2);
1162 // If either is a NaN, return an input NaN
1163 if (g_isnan(f1)) return t1;
1164 if (g_isnan(f2)) return t2;
1166 // If an operand is infinity or the divisor is +/- zero, punt.
1167 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1168 return Type::DOUBLE;
1170 // We must be modulo'ing 2 double constants.
1171 // Make sure that the sign of the fmod is equal to the sign of the dividend
1172 jlong xr = jlong_cast(fmod(f1, f2));
1173 if ((x1 ^ xr) < 0) {
1174 xr ^= min_jlong;
1175 }
1177 return TypeD::make(jdouble_cast(xr));
1178 }
1180 //=============================================================================
1182 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1183 init_req(0, c);
1184 init_req(1, dividend);
1185 init_req(2, divisor);
1186 }
1188 //------------------------------make------------------------------------------
1189 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
1190 Node* n = div_or_mod;
1191 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1192 "only div or mod input pattern accepted");
1194 DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2));
1195 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1196 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1197 return divmod;
1198 }
1200 //------------------------------make------------------------------------------
1201 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
1202 Node* n = div_or_mod;
1203 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1204 "only div or mod input pattern accepted");
1206 DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2));
1207 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1208 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1209 return divmod;
1210 }
1212 //------------------------------match------------------------------------------
1213 // return result(s) along with their RegMask info
1214 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1215 uint ideal_reg = proj->ideal_reg();
1216 RegMask rm;
1217 if (proj->_con == div_proj_num) {
1218 rm = match->divI_proj_mask();
1219 } else {
1220 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1221 rm = match->modI_proj_mask();
1222 }
1223 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1224 }
1227 //------------------------------match------------------------------------------
1228 // return result(s) along with their RegMask info
1229 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1230 uint ideal_reg = proj->ideal_reg();
1231 RegMask rm;
1232 if (proj->_con == div_proj_num) {
1233 rm = match->divL_proj_mask();
1234 } else {
1235 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1236 rm = match->modL_proj_mask();
1237 }
1238 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1239 }