Tue, 02 Nov 2010 09:00:37 -0700
6987135: Performance regression on Intel platform with 32-bits edition between 6u13 and 6u14.
Summary: Use hardware DIV instruction for long division by constant when it is faster than code with multiply.
Reviewed-by: never
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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 verbatim 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_t = phase->type( dividend->in(2) )->isa_int();
114 if( andconi_t && andconi_t->is_con() ) {
115 jint andconi = andconi_t->get_con();
116 if( andconi < 0 && is_power_of_2(-andconi) && (-andconi) >= d ) {
117 if( (-andconi) == d ) // Remove AND if it clears bits which will be shifted
118 dividend = dividend->in(1);
119 needs_rounding = false;
120 }
121 }
122 }
124 // Add rounding to the shift to handle the sign bit
125 int l = log2_intptr(d-1)+1;
126 if (needs_rounding) {
127 // Divide-by-power-of-2 can be made into a shift, but you have to do
128 // more math for the rounding. You need to add 0 for positive
129 // numbers, and "i-1" for negative numbers. Example: i=4, so the
130 // shift is by 2. You need to add 3 to negative dividends and 0 to
131 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
132 // (-2+3)>>2 becomes 0, etc.
134 // Compute 0 or -1, based on sign bit
135 Node *sign = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N - 1)));
136 // Mask sign bit to the low sign bits
137 Node *round = phase->transform(new (phase->C, 3) URShiftINode(sign, phase->intcon(N - l)));
138 // Round up before shifting
139 dividend = phase->transform(new (phase->C, 3) AddINode(dividend, round));
140 }
142 // Shift for division
143 q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l));
145 if (!d_pos) {
146 q = new (phase->C, 3) SubINode(phase->intcon(0), phase->transform(q));
147 }
148 } else {
149 // Attempt the jint constant divide -> multiply transform found in
150 // "Division by Invariant Integers using Multiplication"
151 // by Granlund and Montgomery
152 // See also "Hacker's Delight", chapter 10 by Warren.
154 jint magic_const;
155 jint shift_const;
156 if (magic_int_divide_constants(d, magic_const, shift_const)) {
157 Node *magic = phase->longcon(magic_const);
158 Node *dividend_long = phase->transform(new (phase->C, 2) ConvI2LNode(dividend));
160 // Compute the high half of the dividend x magic multiplication
161 Node *mul_hi = phase->transform(new (phase->C, 3) MulLNode(dividend_long, magic));
163 if (magic_const < 0) {
164 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N)));
165 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
167 // The magic multiplier is too large for a 32 bit constant. We've adjusted
168 // it down by 2^32, but have to add 1 dividend back in after the multiplication.
169 // This handles the "overflow" case described by Granlund and Montgomery.
170 mul_hi = phase->transform(new (phase->C, 3) AddINode(dividend, mul_hi));
172 // Shift over the (adjusted) mulhi
173 if (shift_const != 0) {
174 mul_hi = phase->transform(new (phase->C, 3) RShiftINode(mul_hi, phase->intcon(shift_const)));
175 }
176 } else {
177 // No add is required, we can merge the shifts together.
178 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
179 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
180 }
182 // Get a 0 or -1 from the sign of the dividend.
183 Node *addend0 = mul_hi;
184 Node *addend1 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1)));
186 // If the divisor is negative, swap the order of the input addends;
187 // this has the effect of negating the quotient.
188 if (!d_pos) {
189 Node *temp = addend0; addend0 = addend1; addend1 = temp;
190 }
192 // Adjust the final quotient by subtracting -1 (adding 1)
193 // from the mul_hi.
194 q = new (phase->C, 3) SubINode(addend0, addend1);
195 }
196 }
198 return q;
199 }
201 //---------------------magic_long_divide_constants-----------------------------
202 // Compute magic multiplier and shift constant for converting a 64 bit divide
203 // by constant into a multiply/shift/add series. Return false if calculations
204 // fail.
205 //
206 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
207 // minor type name and parameter changes. Adjusted to 64 bit word width.
208 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) {
209 int64_t p;
210 uint64_t ad, anc, delta, q1, r1, q2, r2, t;
211 const uint64_t two63 = 0x8000000000000000LL; // 2**63.
213 ad = ABS(d);
214 if (d == 0 || d == 1) return false;
215 t = two63 + ((uint64_t)d >> 63);
216 anc = t - 1 - t%ad; // Absolute value of nc.
217 p = 63; // Init. p.
218 q1 = two63/anc; // Init. q1 = 2**p/|nc|.
219 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|).
220 q2 = two63/ad; // Init. q2 = 2**p/|d|.
221 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|).
222 do {
223 p = p + 1;
224 q1 = 2*q1; // Update q1 = 2**p/|nc|.
225 r1 = 2*r1; // Update r1 = rem(2**p, |nc|).
226 if (r1 >= anc) { // (Must be an unsigned
227 q1 = q1 + 1; // comparison here).
228 r1 = r1 - anc;
229 }
230 q2 = 2*q2; // Update q2 = 2**p/|d|.
231 r2 = 2*r2; // Update r2 = rem(2**p, |d|).
232 if (r2 >= ad) { // (Must be an unsigned
233 q2 = q2 + 1; // comparison here).
234 r2 = r2 - ad;
235 }
236 delta = ad - r2;
237 } while (q1 < delta || (q1 == delta && r1 == 0));
239 M = q2 + 1;
240 if (d < 0) M = -M; // Magic number and
241 s = p - 64; // shift amount to return.
243 return true;
244 }
246 //---------------------long_by_long_mulhi--------------------------------------
247 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication
248 static Node* long_by_long_mulhi(PhaseGVN* phase, Node* dividend, jlong magic_const) {
249 // If the architecture supports a 64x64 mulhi, there is
250 // no need to synthesize it in ideal nodes.
251 if (Matcher::has_match_rule(Op_MulHiL)) {
252 Node* v = phase->longcon(magic_const);
253 return new (phase->C, 3) MulHiLNode(dividend, v);
254 }
256 // Taken from Hacker's Delight, Fig. 8-2. Multiply high signed.
257 // (http://www.hackersdelight.org/HDcode/mulhs.c)
258 //
259 // int mulhs(int u, int v) {
260 // unsigned u0, v0, w0;
261 // int u1, v1, w1, w2, t;
262 //
263 // u0 = u & 0xFFFF; u1 = u >> 16;
264 // v0 = v & 0xFFFF; v1 = v >> 16;
265 // w0 = u0*v0;
266 // t = u1*v0 + (w0 >> 16);
267 // w1 = t & 0xFFFF;
268 // w2 = t >> 16;
269 // w1 = u0*v1 + w1;
270 // return u1*v1 + w2 + (w1 >> 16);
271 // }
272 //
273 // Note: The version above is for 32x32 multiplications, while the
274 // following inline comments are adapted to 64x64.
276 const int N = 64;
278 // u0 = u & 0xFFFFFFFF; u1 = u >> 32;
279 Node* u0 = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
280 Node* u1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2)));
282 // v0 = v & 0xFFFFFFFF; v1 = v >> 32;
283 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF);
284 Node* v1 = phase->longcon(magic_const >> (N / 2));
286 // w0 = u0*v0;
287 Node* w0 = phase->transform(new (phase->C, 3) MulLNode(u0, v0));
289 // t = u1*v0 + (w0 >> 32);
290 Node* u1v0 = phase->transform(new (phase->C, 3) MulLNode(u1, v0));
291 Node* temp = phase->transform(new (phase->C, 3) URShiftLNode(w0, phase->intcon(N / 2)));
292 Node* t = phase->transform(new (phase->C, 3) AddLNode(u1v0, temp));
294 // w1 = t & 0xFFFFFFFF;
295 Node* w1 = new (phase->C, 3) AndLNode(t, phase->longcon(0xFFFFFFFF));
297 // w2 = t >> 32;
298 Node* w2 = new (phase->C, 3) RShiftLNode(t, phase->intcon(N / 2));
300 // 6732154: Construct both w1 and w2 before transforming, so t
301 // doesn't go dead prematurely.
302 // 6837011: We need to transform w2 before w1 because the
303 // transformation of w1 could return t.
304 w2 = phase->transform(w2);
305 w1 = phase->transform(w1);
307 // w1 = u0*v1 + w1;
308 Node* u0v1 = phase->transform(new (phase->C, 3) MulLNode(u0, v1));
309 w1 = phase->transform(new (phase->C, 3) AddLNode(u0v1, w1));
311 // return u1*v1 + w2 + (w1 >> 32);
312 Node* u1v1 = phase->transform(new (phase->C, 3) MulLNode(u1, v1));
313 Node* temp1 = phase->transform(new (phase->C, 3) AddLNode(u1v1, w2));
314 Node* temp2 = phase->transform(new (phase->C, 3) RShiftLNode(w1, phase->intcon(N / 2)));
316 return new (phase->C, 3) AddLNode(temp1, temp2);
317 }
320 //--------------------------transform_long_divide------------------------------
321 // Convert a division by constant divisor into an alternate Ideal graph.
322 // Return NULL if no transformation occurs.
323 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
324 // Check for invalid divisors
325 assert( divisor != 0L && divisor != min_jlong,
326 "bad divisor for transforming to long multiply" );
328 bool d_pos = divisor >= 0;
329 jlong d = d_pos ? divisor : -divisor;
330 const int N = 64;
332 // Result
333 Node *q = NULL;
335 if (d == 1) {
336 // division by +/- 1
337 if (!d_pos) {
338 // Just negate the value
339 q = new (phase->C, 3) SubLNode(phase->longcon(0), dividend);
340 }
341 } else if ( is_power_of_2_long(d) ) {
343 // division by +/- a power of 2
345 // See if we can simply do a shift without rounding
346 bool needs_rounding = true;
347 const Type *dt = phase->type(dividend);
348 const TypeLong *dtl = dt->isa_long();
350 if (dtl && dtl->_lo > 0) {
351 // we don't need to round a positive dividend
352 needs_rounding = false;
353 } else if( dividend->Opcode() == Op_AndL ) {
354 // An AND mask of sufficient size clears the low bits and
355 // I can avoid rounding.
356 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long();
357 if( andconl_t && andconl_t->is_con() ) {
358 jlong andconl = andconl_t->get_con();
359 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) {
360 if( (-andconl) == d ) // Remove AND if it clears bits which will be shifted
361 dividend = dividend->in(1);
362 needs_rounding = false;
363 }
364 }
365 }
367 // Add rounding to the shift to handle the sign bit
368 int l = log2_long(d-1)+1;
369 if (needs_rounding) {
370 // Divide-by-power-of-2 can be made into a shift, but you have to do
371 // more math for the rounding. You need to add 0 for positive
372 // numbers, and "i-1" for negative numbers. Example: i=4, so the
373 // shift is by 2. You need to add 3 to negative dividends and 0 to
374 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
375 // (-2+3)>>2 becomes 0, etc.
377 // Compute 0 or -1, based on sign bit
378 Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N - 1)));
379 // Mask sign bit to the low sign bits
380 Node *round = phase->transform(new (phase->C, 3) URShiftLNode(sign, phase->intcon(N - l)));
381 // Round up before shifting
382 dividend = phase->transform(new (phase->C, 3) AddLNode(dividend, round));
383 }
385 // Shift for division
386 q = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(l));
388 if (!d_pos) {
389 q = new (phase->C, 3) SubLNode(phase->longcon(0), phase->transform(q));
390 }
391 } else if ( !Matcher::use_asm_for_ldiv_by_con(d) ) { // Use hardware DIV instruction when
392 // it is faster than code generated below.
393 // Attempt the jlong constant divide -> multiply transform found in
394 // "Division by Invariant Integers using Multiplication"
395 // by Granlund and Montgomery
396 // See also "Hacker's Delight", chapter 10 by Warren.
398 jlong magic_const;
399 jint shift_const;
400 if (magic_long_divide_constants(d, magic_const, shift_const)) {
401 // Compute the high half of the dividend x magic multiplication
402 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
404 // The high half of the 128-bit multiply is computed.
405 if (magic_const < 0) {
406 // The magic multiplier is too large for a 64 bit constant. We've adjusted
407 // it down by 2^64, but have to add 1 dividend back in after the multiplication.
408 // This handles the "overflow" case described by Granlund and Montgomery.
409 mul_hi = phase->transform(new (phase->C, 3) AddLNode(dividend, mul_hi));
410 }
412 // Shift over the (adjusted) mulhi
413 if (shift_const != 0) {
414 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(shift_const)));
415 }
417 // Get a 0 or -1 from the sign of the dividend.
418 Node *addend0 = mul_hi;
419 Node *addend1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N-1)));
421 // If the divisor is negative, swap the order of the input addends;
422 // this has the effect of negating the quotient.
423 if (!d_pos) {
424 Node *temp = addend0; addend0 = addend1; addend1 = temp;
425 }
427 // Adjust the final quotient by subtracting -1 (adding 1)
428 // from the mul_hi.
429 q = new (phase->C, 3) SubLNode(addend0, addend1);
430 }
431 }
433 return q;
434 }
436 //=============================================================================
437 //------------------------------Identity---------------------------------------
438 // If the divisor is 1, we are an identity on the dividend.
439 Node *DivINode::Identity( PhaseTransform *phase ) {
440 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
441 }
443 //------------------------------Idealize---------------------------------------
444 // Divides can be changed to multiplies and/or shifts
445 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
446 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
447 // Don't bother trying to transform a dead node
448 if( in(0) && in(0)->is_top() ) return NULL;
450 const Type *t = phase->type( in(2) );
451 if( t == TypeInt::ONE ) // Identity?
452 return NULL; // Skip it
454 const TypeInt *ti = t->isa_int();
455 if( !ti ) return NULL;
456 if( !ti->is_con() ) return NULL;
457 jint i = ti->get_con(); // Get divisor
459 if (i == 0) return NULL; // Dividing by zero constant does not idealize
461 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
463 // Dividing by MININT does not optimize as a power-of-2 shift.
464 if( i == min_jint ) return NULL;
466 return transform_int_divide( phase, in(1), i );
467 }
469 //------------------------------Value------------------------------------------
470 // A DivINode divides its inputs. The third input is a Control input, used to
471 // prevent hoisting the divide above an unsafe test.
472 const Type *DivINode::Value( PhaseTransform *phase ) const {
473 // Either input is TOP ==> the result is TOP
474 const Type *t1 = phase->type( in(1) );
475 const Type *t2 = phase->type( in(2) );
476 if( t1 == Type::TOP ) return Type::TOP;
477 if( t2 == Type::TOP ) return Type::TOP;
479 // x/x == 1 since we always generate the dynamic divisor check for 0.
480 if( phase->eqv( in(1), in(2) ) )
481 return TypeInt::ONE;
483 // Either input is BOTTOM ==> the result is the local BOTTOM
484 const Type *bot = bottom_type();
485 if( (t1 == bot) || (t2 == bot) ||
486 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
487 return bot;
489 // Divide the two numbers. We approximate.
490 // If divisor is a constant and not zero
491 const TypeInt *i1 = t1->is_int();
492 const TypeInt *i2 = t2->is_int();
493 int widen = MAX2(i1->_widen, i2->_widen);
495 if( i2->is_con() && i2->get_con() != 0 ) {
496 int32 d = i2->get_con(); // Divisor
497 jint lo, hi;
498 if( d >= 0 ) {
499 lo = i1->_lo/d;
500 hi = i1->_hi/d;
501 } else {
502 if( d == -1 && i1->_lo == min_jint ) {
503 // 'min_jint/-1' throws arithmetic exception during compilation
504 lo = min_jint;
505 // do not support holes, 'hi' must go to either min_jint or max_jint:
506 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
507 hi = i1->_hi == min_jint ? min_jint : max_jint;
508 } else {
509 lo = i1->_hi/d;
510 hi = i1->_lo/d;
511 }
512 }
513 return TypeInt::make(lo, hi, widen);
514 }
516 // If the dividend is a constant
517 if( i1->is_con() ) {
518 int32 d = i1->get_con();
519 if( d < 0 ) {
520 if( d == min_jint ) {
521 // (-min_jint) == min_jint == (min_jint / -1)
522 return TypeInt::make(min_jint, max_jint/2 + 1, widen);
523 } else {
524 return TypeInt::make(d, -d, widen);
525 }
526 }
527 return TypeInt::make(-d, d, widen);
528 }
530 // Otherwise we give up all hope
531 return TypeInt::INT;
532 }
535 //=============================================================================
536 //------------------------------Identity---------------------------------------
537 // If the divisor is 1, we are an identity on the dividend.
538 Node *DivLNode::Identity( PhaseTransform *phase ) {
539 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
540 }
542 //------------------------------Idealize---------------------------------------
543 // Dividing by a power of 2 is a shift.
544 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
545 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
546 // Don't bother trying to transform a dead node
547 if( in(0) && in(0)->is_top() ) return NULL;
549 const Type *t = phase->type( in(2) );
550 if( t == TypeLong::ONE ) // Identity?
551 return NULL; // Skip it
553 const TypeLong *tl = t->isa_long();
554 if( !tl ) return NULL;
555 if( !tl->is_con() ) return NULL;
556 jlong l = tl->get_con(); // Get divisor
558 if (l == 0) return NULL; // Dividing by zero constant does not idealize
560 set_req(0,NULL); // Dividing by a not-zero constant; no faulting
562 // Dividing by MINLONG does not optimize as a power-of-2 shift.
563 if( l == min_jlong ) return NULL;
565 return transform_long_divide( phase, in(1), l );
566 }
568 //------------------------------Value------------------------------------------
569 // A DivLNode divides its inputs. The third input is a Control input, used to
570 // prevent hoisting the divide above an unsafe test.
571 const Type *DivLNode::Value( PhaseTransform *phase ) const {
572 // Either input is TOP ==> the result is TOP
573 const Type *t1 = phase->type( in(1) );
574 const Type *t2 = phase->type( in(2) );
575 if( t1 == Type::TOP ) return Type::TOP;
576 if( t2 == Type::TOP ) return Type::TOP;
578 // x/x == 1 since we always generate the dynamic divisor check for 0.
579 if( phase->eqv( in(1), in(2) ) )
580 return TypeLong::ONE;
582 // Either input is BOTTOM ==> the result is the local BOTTOM
583 const Type *bot = bottom_type();
584 if( (t1 == bot) || (t2 == bot) ||
585 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
586 return bot;
588 // Divide the two numbers. We approximate.
589 // If divisor is a constant and not zero
590 const TypeLong *i1 = t1->is_long();
591 const TypeLong *i2 = t2->is_long();
592 int widen = MAX2(i1->_widen, i2->_widen);
594 if( i2->is_con() && i2->get_con() != 0 ) {
595 jlong d = i2->get_con(); // Divisor
596 jlong lo, hi;
597 if( d >= 0 ) {
598 lo = i1->_lo/d;
599 hi = i1->_hi/d;
600 } else {
601 if( d == CONST64(-1) && i1->_lo == min_jlong ) {
602 // 'min_jlong/-1' throws arithmetic exception during compilation
603 lo = min_jlong;
604 // do not support holes, 'hi' must go to either min_jlong or max_jlong:
605 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
606 hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
607 } else {
608 lo = i1->_hi/d;
609 hi = i1->_lo/d;
610 }
611 }
612 return TypeLong::make(lo, hi, widen);
613 }
615 // If the dividend is a constant
616 if( i1->is_con() ) {
617 jlong d = i1->get_con();
618 if( d < 0 ) {
619 if( d == min_jlong ) {
620 // (-min_jlong) == min_jlong == (min_jlong / -1)
621 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
622 } else {
623 return TypeLong::make(d, -d, widen);
624 }
625 }
626 return TypeLong::make(-d, d, widen);
627 }
629 // Otherwise we give up all hope
630 return TypeLong::LONG;
631 }
634 //=============================================================================
635 //------------------------------Value------------------------------------------
636 // An DivFNode divides its inputs. The third input is a Control input, used to
637 // prevent hoisting the divide above an unsafe test.
638 const Type *DivFNode::Value( PhaseTransform *phase ) const {
639 // Either input is TOP ==> the result is TOP
640 const Type *t1 = phase->type( in(1) );
641 const Type *t2 = phase->type( in(2) );
642 if( t1 == Type::TOP ) return Type::TOP;
643 if( t2 == Type::TOP ) return Type::TOP;
645 // Either input is BOTTOM ==> the result is the local BOTTOM
646 const Type *bot = bottom_type();
647 if( (t1 == bot) || (t2 == bot) ||
648 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
649 return bot;
651 // x/x == 1, we ignore 0/0.
652 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
653 // Does not work for variables because of NaN's
654 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
655 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
656 return TypeF::ONE;
658 if( t2 == TypeF::ONE )
659 return t1;
661 // If divisor is a constant and not zero, divide them numbers
662 if( t1->base() == Type::FloatCon &&
663 t2->base() == Type::FloatCon &&
664 t2->getf() != 0.0 ) // could be negative zero
665 return TypeF::make( t1->getf()/t2->getf() );
667 // If the dividend is a constant zero
668 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
669 // Test TypeF::ZERO is not sufficient as it could be negative zero
671 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
672 return TypeF::ZERO;
674 // Otherwise we give up all hope
675 return Type::FLOAT;
676 }
678 //------------------------------isA_Copy---------------------------------------
679 // Dividing by self is 1.
680 // If the divisor is 1, we are an identity on the dividend.
681 Node *DivFNode::Identity( PhaseTransform *phase ) {
682 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
683 }
686 //------------------------------Idealize---------------------------------------
687 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
688 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
689 // Don't bother trying to transform a dead node
690 if( in(0) && in(0)->is_top() ) return NULL;
692 const Type *t2 = phase->type( in(2) );
693 if( t2 == TypeF::ONE ) // Identity?
694 return NULL; // Skip it
696 const TypeF *tf = t2->isa_float_constant();
697 if( !tf ) return NULL;
698 if( tf->base() != Type::FloatCon ) return NULL;
700 // Check for out of range values
701 if( tf->is_nan() || !tf->is_finite() ) return NULL;
703 // Get the value
704 float f = tf->getf();
705 int exp;
707 // Only for special case of dividing by a power of 2
708 if( frexp((double)f, &exp) != 0.5 ) return NULL;
710 // Limit the range of acceptable exponents
711 if( exp < -126 || exp > 126 ) return NULL;
713 // Compute the reciprocal
714 float reciprocal = ((float)1.0) / f;
716 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
718 // return multiplication by the reciprocal
719 return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
720 }
722 //=============================================================================
723 //------------------------------Value------------------------------------------
724 // An DivDNode divides its inputs. The third input is a Control input, used to
725 // prevent hoisting the divide above an unsafe test.
726 const Type *DivDNode::Value( PhaseTransform *phase ) const {
727 // Either input is TOP ==> the result is TOP
728 const Type *t1 = phase->type( in(1) );
729 const Type *t2 = phase->type( in(2) );
730 if( t1 == Type::TOP ) return Type::TOP;
731 if( t2 == Type::TOP ) return Type::TOP;
733 // Either input is BOTTOM ==> the result is the local BOTTOM
734 const Type *bot = bottom_type();
735 if( (t1 == bot) || (t2 == bot) ||
736 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
737 return bot;
739 // x/x == 1, we ignore 0/0.
740 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
741 // Does not work for variables because of NaN's
742 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
743 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
744 return TypeD::ONE;
746 if( t2 == TypeD::ONE )
747 return t1;
749 #if defined(IA32)
750 if (!phase->C->method()->is_strict())
751 // Can't trust native compilers to properly fold strict double
752 // division with round-to-zero on this platform.
753 #endif
754 {
755 // If divisor is a constant and not zero, divide them numbers
756 if( t1->base() == Type::DoubleCon &&
757 t2->base() == Type::DoubleCon &&
758 t2->getd() != 0.0 ) // could be negative zero
759 return TypeD::make( t1->getd()/t2->getd() );
760 }
762 // If the dividend is a constant zero
763 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
764 // Test TypeF::ZERO is not sufficient as it could be negative zero
765 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
766 return TypeD::ZERO;
768 // Otherwise we give up all hope
769 return Type::DOUBLE;
770 }
773 //------------------------------isA_Copy---------------------------------------
774 // Dividing by self is 1.
775 // If the divisor is 1, we are an identity on the dividend.
776 Node *DivDNode::Identity( PhaseTransform *phase ) {
777 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
778 }
780 //------------------------------Idealize---------------------------------------
781 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
782 if (in(0) && remove_dead_region(phase, can_reshape)) return this;
783 // Don't bother trying to transform a dead node
784 if( in(0) && in(0)->is_top() ) return NULL;
786 const Type *t2 = phase->type( in(2) );
787 if( t2 == TypeD::ONE ) // Identity?
788 return NULL; // Skip it
790 const TypeD *td = t2->isa_double_constant();
791 if( !td ) return NULL;
792 if( td->base() != Type::DoubleCon ) return NULL;
794 // Check for out of range values
795 if( td->is_nan() || !td->is_finite() ) return NULL;
797 // Get the value
798 double d = td->getd();
799 int exp;
801 // Only for special case of dividing by a power of 2
802 if( frexp(d, &exp) != 0.5 ) return NULL;
804 // Limit the range of acceptable exponents
805 if( exp < -1021 || exp > 1022 ) return NULL;
807 // Compute the reciprocal
808 double reciprocal = 1.0 / d;
810 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
812 // return multiplication by the reciprocal
813 return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
814 }
816 //=============================================================================
817 //------------------------------Idealize---------------------------------------
818 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
819 // Check for dead control input
820 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
821 // Don't bother trying to transform a dead node
822 if( in(0) && in(0)->is_top() ) return NULL;
824 // Get the modulus
825 const Type *t = phase->type( in(2) );
826 if( t == Type::TOP ) return NULL;
827 const TypeInt *ti = t->is_int();
829 // Check for useless control input
830 // Check for excluding mod-zero case
831 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
832 set_req(0, NULL); // Yank control input
833 return this;
834 }
836 // See if we are MOD'ing by 2^k or 2^k-1.
837 if( !ti->is_con() ) return NULL;
838 jint con = ti->get_con();
840 Node *hook = new (phase->C, 1) Node(1);
842 // First, special check for modulo 2^k-1
843 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
844 uint k = exact_log2(con+1); // Extract k
846 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details.
847 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*/};
848 int trip_count = 1;
849 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
851 // If the unroll factor is not too large, and if conditional moves are
852 // ok, then use this case
853 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
854 Node *x = in(1); // Value being mod'd
855 Node *divisor = in(2); // Also is mask
857 hook->init_req(0, x); // Add a use to x to prevent him from dying
858 // Generate code to reduce X rapidly to nearly 2^k-1.
859 for( int i = 0; i < trip_count; i++ ) {
860 Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) );
861 Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed
862 x = phase->transform( new (phase->C, 3) AddINode(xh,xl) );
863 hook->set_req(0, x);
864 }
866 // Generate sign-fixup code. Was original value positive?
867 // int hack_res = (i >= 0) ? divisor : 1;
868 Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) );
869 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
870 Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
871 // if( x >= hack_res ) x -= divisor;
872 Node *sub = phase->transform( new (phase->C, 3) SubINode( x, divisor ) );
873 Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) );
874 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
875 // Convention is to not transform the return value of an Ideal
876 // since Ideal is expected to return a modified 'this' or a new node.
877 Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT);
878 // cmov2 is now the mod
880 // Now remove the bogus extra edges used to keep things alive
881 if (can_reshape) {
882 phase->is_IterGVN()->remove_dead_node(hook);
883 } else {
884 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
885 }
886 return cmov2;
887 }
888 }
890 // Fell thru, the unroll case is not appropriate. Transform the modulo
891 // into a long multiply/int multiply/subtract case
893 // Cannot handle mod 0, and min_jint isn't handled by the transform
894 if( con == 0 || con == min_jint ) return NULL;
896 // Get the absolute value of the constant; at this point, we can use this
897 jint pos_con = (con >= 0) ? con : -con;
899 // integer Mod 1 is always 0
900 if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO);
902 int log2_con = -1;
904 // If this is a power of two, they maybe we can mask it
905 if( is_power_of_2(pos_con) ) {
906 log2_con = log2_intptr((intptr_t)pos_con);
908 const Type *dt = phase->type(in(1));
909 const TypeInt *dti = dt->isa_int();
911 // See if this can be masked, if the dividend is non-negative
912 if( dti && dti->_lo >= 0 )
913 return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) );
914 }
916 // Save in(1) so that it cannot be changed or deleted
917 hook->init_req(0, in(1));
919 // Divide using the transform from DivI to MulL
920 Node *result = transform_int_divide( phase, in(1), pos_con );
921 if (result != NULL) {
922 Node *divide = phase->transform(result);
924 // Re-multiply, using a shift if this is a power of two
925 Node *mult = NULL;
927 if( log2_con >= 0 )
928 mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) );
929 else
930 mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) );
932 // Finally, subtract the multiplied divided value from the original
933 result = new (phase->C, 3) SubINode( in(1), mult );
934 }
936 // Now remove the bogus extra edges used to keep things alive
937 if (can_reshape) {
938 phase->is_IterGVN()->remove_dead_node(hook);
939 } else {
940 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
941 }
943 // return the value
944 return result;
945 }
947 //------------------------------Value------------------------------------------
948 const Type *ModINode::Value( PhaseTransform *phase ) const {
949 // Either input is TOP ==> the result is TOP
950 const Type *t1 = phase->type( in(1) );
951 const Type *t2 = phase->type( in(2) );
952 if( t1 == Type::TOP ) return Type::TOP;
953 if( t2 == Type::TOP ) return Type::TOP;
955 // We always generate the dynamic check for 0.
956 // 0 MOD X is 0
957 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
958 // X MOD X is 0
959 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
961 // Either input is BOTTOM ==> the result is the local BOTTOM
962 const Type *bot = bottom_type();
963 if( (t1 == bot) || (t2 == bot) ||
964 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
965 return bot;
967 const TypeInt *i1 = t1->is_int();
968 const TypeInt *i2 = t2->is_int();
969 if( !i1->is_con() || !i2->is_con() ) {
970 if( i1->_lo >= 0 && i2->_lo >= 0 )
971 return TypeInt::POS;
972 // If both numbers are not constants, we know little.
973 return TypeInt::INT;
974 }
975 // Mod by zero? Throw exception at runtime!
976 if( !i2->get_con() ) return TypeInt::POS;
978 // We must be modulo'ing 2 float constants.
979 // Check for min_jint % '-1', result is defined to be '0'.
980 if( i1->get_con() == min_jint && i2->get_con() == -1 )
981 return TypeInt::ZERO;
983 return TypeInt::make( i1->get_con() % i2->get_con() );
984 }
987 //=============================================================================
988 //------------------------------Idealize---------------------------------------
989 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
990 // Check for dead control input
991 if( in(0) && remove_dead_region(phase, can_reshape) ) return this;
992 // Don't bother trying to transform a dead node
993 if( in(0) && in(0)->is_top() ) return NULL;
995 // Get the modulus
996 const Type *t = phase->type( in(2) );
997 if( t == Type::TOP ) return NULL;
998 const TypeLong *tl = t->is_long();
1000 // Check for useless control input
1001 // Check for excluding mod-zero case
1002 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
1003 set_req(0, NULL); // Yank control input
1004 return this;
1005 }
1007 // See if we are MOD'ing by 2^k or 2^k-1.
1008 if( !tl->is_con() ) return NULL;
1009 jlong con = tl->get_con();
1011 Node *hook = new (phase->C, 1) Node(1);
1013 // Expand mod
1014 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
1015 uint k = exact_log2_long(con+1); // Extract k
1017 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details.
1018 // Used to help a popular random number generator which does a long-mod
1019 // of 2^31-1 and shows up in SpecJBB and SciMark.
1020 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*/};
1021 int trip_count = 1;
1022 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
1024 // If the unroll factor is not too large, and if conditional moves are
1025 // ok, then use this case
1026 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
1027 Node *x = in(1); // Value being mod'd
1028 Node *divisor = in(2); // Also is mask
1030 hook->init_req(0, x); // Add a use to x to prevent him from dying
1031 // Generate code to reduce X rapidly to nearly 2^k-1.
1032 for( int i = 0; i < trip_count; i++ ) {
1033 Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) );
1034 Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed
1035 x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) );
1036 hook->set_req(0, x); // Add a use to x to prevent him from dying
1037 }
1039 // Generate sign-fixup code. Was original value positive?
1040 // long hack_res = (i >= 0) ? divisor : CONST64(1);
1041 Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) );
1042 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
1043 Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
1044 // if( x >= hack_res ) x -= divisor;
1045 Node *sub = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) );
1046 Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) );
1047 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
1048 // Convention is to not transform the return value of an Ideal
1049 // since Ideal is expected to return a modified 'this' or a new node.
1050 Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG);
1051 // cmov2 is now the mod
1053 // Now remove the bogus extra edges used to keep things alive
1054 if (can_reshape) {
1055 phase->is_IterGVN()->remove_dead_node(hook);
1056 } else {
1057 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1058 }
1059 return cmov2;
1060 }
1061 }
1063 // Fell thru, the unroll case is not appropriate. Transform the modulo
1064 // into a long multiply/int multiply/subtract case
1066 // Cannot handle mod 0, and min_jlong isn't handled by the transform
1067 if( con == 0 || con == min_jlong ) return NULL;
1069 // Get the absolute value of the constant; at this point, we can use this
1070 jlong pos_con = (con >= 0) ? con : -con;
1072 // integer Mod 1 is always 0
1073 if( pos_con == 1 ) return new (phase->C, 1) ConLNode(TypeLong::ZERO);
1075 int log2_con = -1;
1077 // If this is a power of two, then maybe we can mask it
1078 if( is_power_of_2_long(pos_con) ) {
1079 log2_con = exact_log2_long(pos_con);
1081 const Type *dt = phase->type(in(1));
1082 const TypeLong *dtl = dt->isa_long();
1084 // See if this can be masked, if the dividend is non-negative
1085 if( dtl && dtl->_lo >= 0 )
1086 return ( new (phase->C, 3) AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
1087 }
1089 // Save in(1) so that it cannot be changed or deleted
1090 hook->init_req(0, in(1));
1092 // Divide using the transform from DivL to MulL
1093 Node *result = transform_long_divide( phase, in(1), pos_con );
1094 if (result != NULL) {
1095 Node *divide = phase->transform(result);
1097 // Re-multiply, using a shift if this is a power of two
1098 Node *mult = NULL;
1100 if( log2_con >= 0 )
1101 mult = phase->transform( new (phase->C, 3) LShiftLNode( divide, phase->intcon( log2_con ) ) );
1102 else
1103 mult = phase->transform( new (phase->C, 3) MulLNode( divide, phase->longcon( pos_con ) ) );
1105 // Finally, subtract the multiplied divided value from the original
1106 result = new (phase->C, 3) SubLNode( in(1), mult );
1107 }
1109 // Now remove the bogus extra edges used to keep things alive
1110 if (can_reshape) {
1111 phase->is_IterGVN()->remove_dead_node(hook);
1112 } else {
1113 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase
1114 }
1116 // return the value
1117 return result;
1118 }
1120 //------------------------------Value------------------------------------------
1121 const Type *ModLNode::Value( PhaseTransform *phase ) const {
1122 // Either input is TOP ==> the result is TOP
1123 const Type *t1 = phase->type( in(1) );
1124 const Type *t2 = phase->type( in(2) );
1125 if( t1 == Type::TOP ) return Type::TOP;
1126 if( t2 == Type::TOP ) return Type::TOP;
1128 // We always generate the dynamic check for 0.
1129 // 0 MOD X is 0
1130 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
1131 // X MOD X is 0
1132 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
1134 // Either input is BOTTOM ==> the result is the local BOTTOM
1135 const Type *bot = bottom_type();
1136 if( (t1 == bot) || (t2 == bot) ||
1137 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1138 return bot;
1140 const TypeLong *i1 = t1->is_long();
1141 const TypeLong *i2 = t2->is_long();
1142 if( !i1->is_con() || !i2->is_con() ) {
1143 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
1144 return TypeLong::POS;
1145 // If both numbers are not constants, we know little.
1146 return TypeLong::LONG;
1147 }
1148 // Mod by zero? Throw exception at runtime!
1149 if( !i2->get_con() ) return TypeLong::POS;
1151 // We must be modulo'ing 2 float constants.
1152 // Check for min_jint % '-1', result is defined to be '0'.
1153 if( i1->get_con() == min_jlong && i2->get_con() == -1 )
1154 return TypeLong::ZERO;
1156 return TypeLong::make( i1->get_con() % i2->get_con() );
1157 }
1160 //=============================================================================
1161 //------------------------------Value------------------------------------------
1162 const Type *ModFNode::Value( PhaseTransform *phase ) const {
1163 // Either input is TOP ==> the result is TOP
1164 const Type *t1 = phase->type( in(1) );
1165 const Type *t2 = phase->type( in(2) );
1166 if( t1 == Type::TOP ) return Type::TOP;
1167 if( t2 == Type::TOP ) return Type::TOP;
1169 // Either input is BOTTOM ==> the result is the local BOTTOM
1170 const Type *bot = bottom_type();
1171 if( (t1 == bot) || (t2 == bot) ||
1172 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1173 return bot;
1175 // If either number is not a constant, we know nothing.
1176 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
1177 return Type::FLOAT; // note: x%x can be either NaN or 0
1178 }
1180 float f1 = t1->getf();
1181 float f2 = t2->getf();
1182 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1
1183 jint x2 = jint_cast(f2);
1185 // If either is a NaN, return an input NaN
1186 if (g_isnan(f1)) return t1;
1187 if (g_isnan(f2)) return t2;
1189 // If an operand is infinity or the divisor is +/- zero, punt.
1190 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
1191 return Type::FLOAT;
1193 // We must be modulo'ing 2 float constants.
1194 // Make sure that the sign of the fmod is equal to the sign of the dividend
1195 jint xr = jint_cast(fmod(f1, f2));
1196 if ((x1 ^ xr) < 0) {
1197 xr ^= min_jint;
1198 }
1200 return TypeF::make(jfloat_cast(xr));
1201 }
1204 //=============================================================================
1205 //------------------------------Value------------------------------------------
1206 const Type *ModDNode::Value( PhaseTransform *phase ) const {
1207 // Either input is TOP ==> the result is TOP
1208 const Type *t1 = phase->type( in(1) );
1209 const Type *t2 = phase->type( in(2) );
1210 if( t1 == Type::TOP ) return Type::TOP;
1211 if( t2 == Type::TOP ) return Type::TOP;
1213 // Either input is BOTTOM ==> the result is the local BOTTOM
1214 const Type *bot = bottom_type();
1215 if( (t1 == bot) || (t2 == bot) ||
1216 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
1217 return bot;
1219 // If either number is not a constant, we know nothing.
1220 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
1221 return Type::DOUBLE; // note: x%x can be either NaN or 0
1222 }
1224 double f1 = t1->getd();
1225 double f2 = t2->getd();
1226 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1
1227 jlong x2 = jlong_cast(f2);
1229 // If either is a NaN, return an input NaN
1230 if (g_isnan(f1)) return t1;
1231 if (g_isnan(f2)) return t2;
1233 // If an operand is infinity or the divisor is +/- zero, punt.
1234 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
1235 return Type::DOUBLE;
1237 // We must be modulo'ing 2 double constants.
1238 // Make sure that the sign of the fmod is equal to the sign of the dividend
1239 jlong xr = jlong_cast(fmod(f1, f2));
1240 if ((x1 ^ xr) < 0) {
1241 xr ^= min_jlong;
1242 }
1244 return TypeD::make(jdouble_cast(xr));
1245 }
1247 //=============================================================================
1249 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
1250 init_req(0, c);
1251 init_req(1, dividend);
1252 init_req(2, divisor);
1253 }
1255 //------------------------------make------------------------------------------
1256 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
1257 Node* n = div_or_mod;
1258 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
1259 "only div or mod input pattern accepted");
1261 DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2));
1262 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1263 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1264 return divmod;
1265 }
1267 //------------------------------make------------------------------------------
1268 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
1269 Node* n = div_or_mod;
1270 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
1271 "only div or mod input pattern accepted");
1273 DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2));
1274 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
1275 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
1276 return divmod;
1277 }
1279 //------------------------------match------------------------------------------
1280 // return result(s) along with their RegMask info
1281 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
1282 uint ideal_reg = proj->ideal_reg();
1283 RegMask rm;
1284 if (proj->_con == div_proj_num) {
1285 rm = match->divI_proj_mask();
1286 } else {
1287 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1288 rm = match->modI_proj_mask();
1289 }
1290 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1291 }
1294 //------------------------------match------------------------------------------
1295 // return result(s) along with their RegMask info
1296 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
1297 uint ideal_reg = proj->ideal_reg();
1298 RegMask rm;
1299 if (proj->_con == div_proj_num) {
1300 rm = match->divL_proj_mask();
1301 } else {
1302 assert(proj->_con == mod_proj_num, "must be div or mod projection");
1303 rm = match->modL_proj_mask();
1304 }
1305 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
1306 }