divnode.cpp revision 605:98cb887364d3
1/* 2 * Copyright 1997-2009 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 */ 24 25// Portions of code courtesy of Clifford Click 26 27// Optimization - Graph Style 28 29#include "incls/_precompiled.incl" 30#include "incls/_divnode.cpp.incl" 31#include <math.h> 32 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. 40static 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. 44 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)); 70 71 M = q2 + 1; 72 if (d < 0) M = -M; // Magic number and 73 s = p - 32; // shift amount to return. 74 75 return true; 76} 77 78//--------------------------transform_int_divide------------------------------- 79// Convert a division by constant divisor into an alternate Ideal graph. 80// Return NULL if no transformation occurs. 81static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) { 82 83 // Check for invalid divisors 84 assert( divisor != 0 && divisor != min_jint, 85 "bad divisor for transforming to long multiply" ); 86 87 bool d_pos = divisor >= 0; 88 jint d = d_pos ? divisor : -divisor; 89 const int N = 32; 90 91 // Result 92 Node *q = NULL; 93 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 2 102 103 // 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 dividend = dividend->in(1); 118 needs_rounding = false; 119 } 120 } 121 } 122 123 // Add rounding to the shift to handle the sign bit 124 int l = log2_intptr(d-1)+1; 125 if (needs_rounding) { 126 // Divide-by-power-of-2 can be made into a shift, but you have to do 127 // more math for the rounding. You need to add 0 for positive 128 // numbers, and "i-1" for negative numbers. Example: i=4, so the 129 // shift is by 2. You need to add 3 to negative dividends and 0 to 130 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1, 131 // (-2+3)>>2 becomes 0, etc. 132 133 // Compute 0 or -1, based on sign bit 134 Node *sign = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N - 1))); 135 // Mask sign bit to the low sign bits 136 Node *round = phase->transform(new (phase->C, 3) URShiftINode(sign, phase->intcon(N - l))); 137 // Round up before shifting 138 dividend = phase->transform(new (phase->C, 3) AddINode(dividend, round)); 139 } 140 141 // Shift for division 142 q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l)); 143 144 if (!d_pos) { 145 q = new (phase->C, 3) SubINode(phase->intcon(0), phase->transform(q)); 146 } 147 } else { 148 // Attempt the jint constant divide -> multiply transform found in 149 // "Division by Invariant Integers using Multiplication" 150 // by Granlund and Montgomery 151 // See also "Hacker's Delight", chapter 10 by Warren. 152 153 jint magic_const; 154 jint shift_const; 155 if (magic_int_divide_constants(d, magic_const, shift_const)) { 156 Node *magic = phase->longcon(magic_const); 157 Node *dividend_long = phase->transform(new (phase->C, 2) ConvI2LNode(dividend)); 158 159 // Compute the high half of the dividend x magic multiplication 160 Node *mul_hi = phase->transform(new (phase->C, 3) MulLNode(dividend_long, magic)); 161 162 if (magic_const < 0) { 163 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N))); 164 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi)); 165 166 // The magic multiplier is too large for a 32 bit constant. We've adjusted 167 // it down by 2^32, but have to add 1 dividend back in after the multiplication. 168 // This handles the "overflow" case described by Granlund and Montgomery. 169 mul_hi = phase->transform(new (phase->C, 3) AddINode(dividend, mul_hi)); 170 171 // Shift over the (adjusted) mulhi 172 if (shift_const != 0) { 173 mul_hi = phase->transform(new (phase->C, 3) RShiftINode(mul_hi, phase->intcon(shift_const))); 174 } 175 } else { 176 // No add is required, we can merge the shifts together. 177 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N + shift_const))); 178 mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi)); 179 } 180 181 // Get a 0 or -1 from the sign of the dividend. 182 Node *addend0 = mul_hi; 183 Node *addend1 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1))); 184 185 // If the divisor is negative, swap the order of the input addends; 186 // this has the effect of negating the quotient. 187 if (!d_pos) { 188 Node *temp = addend0; addend0 = addend1; addend1 = temp; 189 } 190 191 // Adjust the final quotient by subtracting -1 (adding 1) 192 // from the mul_hi. 193 q = new (phase->C, 3) SubINode(addend0, addend1); 194 } 195 } 196 197 return q; 198} 199 200//---------------------magic_long_divide_constants----------------------------- 201// Compute magic multiplier and shift constant for converting a 64 bit divide 202// by constant into a multiply/shift/add series. Return false if calculations 203// fail. 204// 205// Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with 206// minor type name and parameter changes. Adjusted to 64 bit word width. 207static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) { 208 int64_t p; 209 uint64_t ad, anc, delta, q1, r1, q2, r2, t; 210 const uint64_t two63 = 0x8000000000000000LL; // 2**63. 211 212 ad = ABS(d); 213 if (d == 0 || d == 1) return false; 214 t = two63 + ((uint64_t)d >> 63); 215 anc = t - 1 - t%ad; // Absolute value of nc. 216 p = 63; // Init. p. 217 q1 = two63/anc; // Init. q1 = 2**p/|nc|. 218 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|). 219 q2 = two63/ad; // Init. q2 = 2**p/|d|. 220 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|). 221 do { 222 p = p + 1; 223 q1 = 2*q1; // Update q1 = 2**p/|nc|. 224 r1 = 2*r1; // Update r1 = rem(2**p, |nc|). 225 if (r1 >= anc) { // (Must be an unsigned 226 q1 = q1 + 1; // comparison here). 227 r1 = r1 - anc; 228 } 229 q2 = 2*q2; // Update q2 = 2**p/|d|. 230 r2 = 2*r2; // Update r2 = rem(2**p, |d|). 231 if (r2 >= ad) { // (Must be an unsigned 232 q2 = q2 + 1; // comparison here). 233 r2 = r2 - ad; 234 } 235 delta = ad - r2; 236 } while (q1 < delta || (q1 == delta && r1 == 0)); 237 238 M = q2 + 1; 239 if (d < 0) M = -M; // Magic number and 240 s = p - 64; // shift amount to return. 241 242 return true; 243} 244 245//---------------------long_by_long_mulhi-------------------------------------- 246// Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication 247static Node* long_by_long_mulhi(PhaseGVN* phase, Node* dividend, jlong magic_const) { 248 // If the architecture supports a 64x64 mulhi, there is 249 // no need to synthesize it in ideal nodes. 250 if (Matcher::has_match_rule(Op_MulHiL)) { 251 Node* v = phase->longcon(magic_const); 252 return new (phase->C, 3) MulHiLNode(dividend, v); 253 } 254 255 // Taken from Hacker's Delight, Fig. 8-2. Multiply high signed. 256 // (http://www.hackersdelight.org/HDcode/mulhs.c) 257 // 258 // int mulhs(int u, int v) { 259 // unsigned u0, v0, w0; 260 // int u1, v1, w1, w2, t; 261 // 262 // u0 = u & 0xFFFF; u1 = u >> 16; 263 // v0 = v & 0xFFFF; v1 = v >> 16; 264 // w0 = u0*v0; 265 // t = u1*v0 + (w0 >> 16); 266 // w1 = t & 0xFFFF; 267 // w2 = t >> 16; 268 // w1 = u0*v1 + w1; 269 // return u1*v1 + w2 + (w1 >> 16); 270 // } 271 // 272 // Note: The version above is for 32x32 multiplications, while the 273 // following inline comments are adapted to 64x64. 274 275 const int N = 64; 276 277 // u0 = u & 0xFFFFFFFF; u1 = u >> 32; 278 Node* u0 = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF))); 279 Node* u1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2))); 280 281 // v0 = v & 0xFFFFFFFF; v1 = v >> 32; 282 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF); 283 Node* v1 = phase->longcon(magic_const >> (N / 2)); 284 285 // w0 = u0*v0; 286 Node* w0 = phase->transform(new (phase->C, 3) MulLNode(u0, v0)); 287 288 // t = u1*v0 + (w0 >> 32); 289 Node* u1v0 = phase->transform(new (phase->C, 3) MulLNode(u1, v0)); 290 Node* temp = phase->transform(new (phase->C, 3) URShiftLNode(w0, phase->intcon(N / 2))); 291 Node* t = phase->transform(new (phase->C, 3) AddLNode(u1v0, temp)); 292 293 // w1 = t & 0xFFFFFFFF; 294 Node* w1 = new (phase->C, 3) AndLNode(t, phase->longcon(0xFFFFFFFF)); 295 296 // w2 = t >> 32; 297 Node* w2 = new (phase->C, 3) RShiftLNode(t, phase->intcon(N / 2)); 298 299 // 6732154: Construct both w1 and w2 before transforming, so t 300 // doesn't go dead prematurely. 301 w1 = phase->transform(w1); 302 w2 = phase->transform(w2); 303 304 // w1 = u0*v1 + w1; 305 Node* u0v1 = phase->transform(new (phase->C, 3) MulLNode(u0, v1)); 306 w1 = phase->transform(new (phase->C, 3) AddLNode(u0v1, w1)); 307 308 // return u1*v1 + w2 + (w1 >> 32); 309 Node* u1v1 = phase->transform(new (phase->C, 3) MulLNode(u1, v1)); 310 Node* temp1 = phase->transform(new (phase->C, 3) AddLNode(u1v1, w2)); 311 Node* temp2 = phase->transform(new (phase->C, 3) RShiftLNode(w1, phase->intcon(N / 2))); 312 313 return new (phase->C, 3) AddLNode(temp1, temp2); 314} 315 316 317//--------------------------transform_long_divide------------------------------ 318// Convert a division by constant divisor into an alternate Ideal graph. 319// Return NULL if no transformation occurs. 320static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) { 321 // Check for invalid divisors 322 assert( divisor != 0L && divisor != min_jlong, 323 "bad divisor for transforming to long multiply" ); 324 325 bool d_pos = divisor >= 0; 326 jlong d = d_pos ? divisor : -divisor; 327 const int N = 64; 328 329 // Result 330 Node *q = NULL; 331 332 if (d == 1) { 333 // division by +/- 1 334 if (!d_pos) { 335 // Just negate the value 336 q = new (phase->C, 3) SubLNode(phase->longcon(0), dividend); 337 } 338 } else if ( is_power_of_2_long(d) ) { 339 340 // division by +/- a power of 2 341 342 // See if we can simply do a shift without rounding 343 bool needs_rounding = true; 344 const Type *dt = phase->type(dividend); 345 const TypeLong *dtl = dt->isa_long(); 346 347 if (dtl && dtl->_lo > 0) { 348 // we don't need to round a positive dividend 349 needs_rounding = false; 350 } else if( dividend->Opcode() == Op_AndL ) { 351 // An AND mask of sufficient size clears the low bits and 352 // I can avoid rounding. 353 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long(); 354 if( andconl_t && andconl_t->is_con() ) { 355 jlong andconl = andconl_t->get_con(); 356 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) { 357 dividend = dividend->in(1); 358 needs_rounding = false; 359 } 360 } 361 } 362 363 // Add rounding to the shift to handle the sign bit 364 int l = log2_long(d-1)+1; 365 if (needs_rounding) { 366 // Divide-by-power-of-2 can be made into a shift, but you have to do 367 // more math for the rounding. You need to add 0 for positive 368 // numbers, and "i-1" for negative numbers. Example: i=4, so the 369 // shift is by 2. You need to add 3 to negative dividends and 0 to 370 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1, 371 // (-2+3)>>2 becomes 0, etc. 372 373 // Compute 0 or -1, based on sign bit 374 Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N - 1))); 375 // Mask sign bit to the low sign bits 376 Node *round = phase->transform(new (phase->C, 3) URShiftLNode(sign, phase->intcon(N - l))); 377 // Round up before shifting 378 dividend = phase->transform(new (phase->C, 3) AddLNode(dividend, round)); 379 } 380 381 // Shift for division 382 q = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(l)); 383 384 if (!d_pos) { 385 q = new (phase->C, 3) SubLNode(phase->longcon(0), phase->transform(q)); 386 } 387 } else { 388 // Attempt the jlong constant divide -> multiply transform found in 389 // "Division by Invariant Integers using Multiplication" 390 // by Granlund and Montgomery 391 // See also "Hacker's Delight", chapter 10 by Warren. 392 393 jlong magic_const; 394 jint shift_const; 395 if (magic_long_divide_constants(d, magic_const, shift_const)) { 396 // Compute the high half of the dividend x magic multiplication 397 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const)); 398 399 // The high half of the 128-bit multiply is computed. 400 if (magic_const < 0) { 401 // The magic multiplier is too large for a 64 bit constant. We've adjusted 402 // it down by 2^64, but have to add 1 dividend back in after the multiplication. 403 // This handles the "overflow" case described by Granlund and Montgomery. 404 mul_hi = phase->transform(new (phase->C, 3) AddLNode(dividend, mul_hi)); 405 } 406 407 // Shift over the (adjusted) mulhi 408 if (shift_const != 0) { 409 mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(shift_const))); 410 } 411 412 // Get a 0 or -1 from the sign of the dividend. 413 Node *addend0 = mul_hi; 414 Node *addend1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N-1))); 415 416 // If the divisor is negative, swap the order of the input addends; 417 // this has the effect of negating the quotient. 418 if (!d_pos) { 419 Node *temp = addend0; addend0 = addend1; addend1 = temp; 420 } 421 422 // Adjust the final quotient by subtracting -1 (adding 1) 423 // from the mul_hi. 424 q = new (phase->C, 3) SubLNode(addend0, addend1); 425 } 426 } 427 428 return q; 429} 430 431//============================================================================= 432//------------------------------Identity--------------------------------------- 433// If the divisor is 1, we are an identity on the dividend. 434Node *DivINode::Identity( PhaseTransform *phase ) { 435 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this; 436} 437 438//------------------------------Idealize--------------------------------------- 439// Divides can be changed to multiplies and/or shifts 440Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) { 441 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 442 // Don't bother trying to transform a dead node 443 if( in(0) && in(0)->is_top() ) return NULL; 444 445 const Type *t = phase->type( in(2) ); 446 if( t == TypeInt::ONE ) // Identity? 447 return NULL; // Skip it 448 449 const TypeInt *ti = t->isa_int(); 450 if( !ti ) return NULL; 451 if( !ti->is_con() ) return NULL; 452 jint i = ti->get_con(); // Get divisor 453 454 if (i == 0) return NULL; // Dividing by zero constant does not idealize 455 456 set_req(0,NULL); // Dividing by a not-zero constant; no faulting 457 458 // Dividing by MININT does not optimize as a power-of-2 shift. 459 if( i == min_jint ) return NULL; 460 461 return transform_int_divide( phase, in(1), i ); 462} 463 464//------------------------------Value------------------------------------------ 465// A DivINode divides its inputs. The third input is a Control input, used to 466// prevent hoisting the divide above an unsafe test. 467const Type *DivINode::Value( PhaseTransform *phase ) const { 468 // Either input is TOP ==> the result is TOP 469 const Type *t1 = phase->type( in(1) ); 470 const Type *t2 = phase->type( in(2) ); 471 if( t1 == Type::TOP ) return Type::TOP; 472 if( t2 == Type::TOP ) return Type::TOP; 473 474 // x/x == 1 since we always generate the dynamic divisor check for 0. 475 if( phase->eqv( in(1), in(2) ) ) 476 return TypeInt::ONE; 477 478 // Either input is BOTTOM ==> the result is the local BOTTOM 479 const Type *bot = bottom_type(); 480 if( (t1 == bot) || (t2 == bot) || 481 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 482 return bot; 483 484 // Divide the two numbers. We approximate. 485 // If divisor is a constant and not zero 486 const TypeInt *i1 = t1->is_int(); 487 const TypeInt *i2 = t2->is_int(); 488 int widen = MAX2(i1->_widen, i2->_widen); 489 490 if( i2->is_con() && i2->get_con() != 0 ) { 491 int32 d = i2->get_con(); // Divisor 492 jint lo, hi; 493 if( d >= 0 ) { 494 lo = i1->_lo/d; 495 hi = i1->_hi/d; 496 } else { 497 if( d == -1 && i1->_lo == min_jint ) { 498 // 'min_jint/-1' throws arithmetic exception during compilation 499 lo = min_jint; 500 // do not support holes, 'hi' must go to either min_jint or max_jint: 501 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint] 502 hi = i1->_hi == min_jint ? min_jint : max_jint; 503 } else { 504 lo = i1->_hi/d; 505 hi = i1->_lo/d; 506 } 507 } 508 return TypeInt::make(lo, hi, widen); 509 } 510 511 // If the dividend is a constant 512 if( i1->is_con() ) { 513 int32 d = i1->get_con(); 514 if( d < 0 ) { 515 if( d == min_jint ) { 516 // (-min_jint) == min_jint == (min_jint / -1) 517 return TypeInt::make(min_jint, max_jint/2 + 1, widen); 518 } else { 519 return TypeInt::make(d, -d, widen); 520 } 521 } 522 return TypeInt::make(-d, d, widen); 523 } 524 525 // Otherwise we give up all hope 526 return TypeInt::INT; 527} 528 529 530//============================================================================= 531//------------------------------Identity--------------------------------------- 532// If the divisor is 1, we are an identity on the dividend. 533Node *DivLNode::Identity( PhaseTransform *phase ) { 534 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this; 535} 536 537//------------------------------Idealize--------------------------------------- 538// Dividing by a power of 2 is a shift. 539Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) { 540 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 541 // Don't bother trying to transform a dead node 542 if( in(0) && in(0)->is_top() ) return NULL; 543 544 const Type *t = phase->type( in(2) ); 545 if( t == TypeLong::ONE ) // Identity? 546 return NULL; // Skip it 547 548 const TypeLong *tl = t->isa_long(); 549 if( !tl ) return NULL; 550 if( !tl->is_con() ) return NULL; 551 jlong l = tl->get_con(); // Get divisor 552 553 if (l == 0) return NULL; // Dividing by zero constant does not idealize 554 555 set_req(0,NULL); // Dividing by a not-zero constant; no faulting 556 557 // Dividing by MININT does not optimize as a power-of-2 shift. 558 if( l == min_jlong ) return NULL; 559 560 return transform_long_divide( phase, in(1), l ); 561} 562 563//------------------------------Value------------------------------------------ 564// A DivLNode divides its inputs. The third input is a Control input, used to 565// prevent hoisting the divide above an unsafe test. 566const Type *DivLNode::Value( PhaseTransform *phase ) const { 567 // Either input is TOP ==> the result is TOP 568 const Type *t1 = phase->type( in(1) ); 569 const Type *t2 = phase->type( in(2) ); 570 if( t1 == Type::TOP ) return Type::TOP; 571 if( t2 == Type::TOP ) return Type::TOP; 572 573 // x/x == 1 since we always generate the dynamic divisor check for 0. 574 if( phase->eqv( in(1), in(2) ) ) 575 return TypeLong::ONE; 576 577 // Either input is BOTTOM ==> the result is the local BOTTOM 578 const Type *bot = bottom_type(); 579 if( (t1 == bot) || (t2 == bot) || 580 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 581 return bot; 582 583 // Divide the two numbers. We approximate. 584 // If divisor is a constant and not zero 585 const TypeLong *i1 = t1->is_long(); 586 const TypeLong *i2 = t2->is_long(); 587 int widen = MAX2(i1->_widen, i2->_widen); 588 589 if( i2->is_con() && i2->get_con() != 0 ) { 590 jlong d = i2->get_con(); // Divisor 591 jlong lo, hi; 592 if( d >= 0 ) { 593 lo = i1->_lo/d; 594 hi = i1->_hi/d; 595 } else { 596 if( d == CONST64(-1) && i1->_lo == min_jlong ) { 597 // 'min_jlong/-1' throws arithmetic exception during compilation 598 lo = min_jlong; 599 // do not support holes, 'hi' must go to either min_jlong or max_jlong: 600 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong] 601 hi = i1->_hi == min_jlong ? min_jlong : max_jlong; 602 } else { 603 lo = i1->_hi/d; 604 hi = i1->_lo/d; 605 } 606 } 607 return TypeLong::make(lo, hi, widen); 608 } 609 610 // If the dividend is a constant 611 if( i1->is_con() ) { 612 jlong d = i1->get_con(); 613 if( d < 0 ) { 614 if( d == min_jlong ) { 615 // (-min_jlong) == min_jlong == (min_jlong / -1) 616 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen); 617 } else { 618 return TypeLong::make(d, -d, widen); 619 } 620 } 621 return TypeLong::make(-d, d, widen); 622 } 623 624 // Otherwise we give up all hope 625 return TypeLong::LONG; 626} 627 628 629//============================================================================= 630//------------------------------Value------------------------------------------ 631// An DivFNode divides its inputs. The third input is a Control input, used to 632// prevent hoisting the divide above an unsafe test. 633const Type *DivFNode::Value( PhaseTransform *phase ) const { 634 // Either input is TOP ==> the result is TOP 635 const Type *t1 = phase->type( in(1) ); 636 const Type *t2 = phase->type( in(2) ); 637 if( t1 == Type::TOP ) return Type::TOP; 638 if( t2 == Type::TOP ) return Type::TOP; 639 640 // Either input is BOTTOM ==> the result is the local BOTTOM 641 const Type *bot = bottom_type(); 642 if( (t1 == bot) || (t2 == bot) || 643 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 644 return bot; 645 646 // x/x == 1, we ignore 0/0. 647 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 648 // Does not work for variables because of NaN's 649 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon) 650 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN 651 return TypeF::ONE; 652 653 if( t2 == TypeF::ONE ) 654 return t1; 655 656 // If divisor is a constant and not zero, divide them numbers 657 if( t1->base() == Type::FloatCon && 658 t2->base() == Type::FloatCon && 659 t2->getf() != 0.0 ) // could be negative zero 660 return TypeF::make( t1->getf()/t2->getf() ); 661 662 // If the dividend is a constant zero 663 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 664 // Test TypeF::ZERO is not sufficient as it could be negative zero 665 666 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 ) 667 return TypeF::ZERO; 668 669 // Otherwise we give up all hope 670 return Type::FLOAT; 671} 672 673//------------------------------isA_Copy--------------------------------------- 674// Dividing by self is 1. 675// If the divisor is 1, we are an identity on the dividend. 676Node *DivFNode::Identity( PhaseTransform *phase ) { 677 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this; 678} 679 680 681//------------------------------Idealize--------------------------------------- 682Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 683 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 684 // Don't bother trying to transform a dead node 685 if( in(0) && in(0)->is_top() ) return NULL; 686 687 const Type *t2 = phase->type( in(2) ); 688 if( t2 == TypeF::ONE ) // Identity? 689 return NULL; // Skip it 690 691 const TypeF *tf = t2->isa_float_constant(); 692 if( !tf ) return NULL; 693 if( tf->base() != Type::FloatCon ) return NULL; 694 695 // Check for out of range values 696 if( tf->is_nan() || !tf->is_finite() ) return NULL; 697 698 // Get the value 699 float f = tf->getf(); 700 int exp; 701 702 // Only for special case of dividing by a power of 2 703 if( frexp((double)f, &exp) != 0.5 ) return NULL; 704 705 // Limit the range of acceptable exponents 706 if( exp < -126 || exp > 126 ) return NULL; 707 708 // Compute the reciprocal 709 float reciprocal = ((float)1.0) / f; 710 711 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); 712 713 // return multiplication by the reciprocal 714 return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal)))); 715} 716 717//============================================================================= 718//------------------------------Value------------------------------------------ 719// An DivDNode divides its inputs. The third input is a Control input, used to 720// prevent hoisting the divide above an unsafe test. 721const Type *DivDNode::Value( PhaseTransform *phase ) const { 722 // Either input is TOP ==> the result is TOP 723 const Type *t1 = phase->type( in(1) ); 724 const Type *t2 = phase->type( in(2) ); 725 if( t1 == Type::TOP ) return Type::TOP; 726 if( t2 == Type::TOP ) return Type::TOP; 727 728 // Either input is BOTTOM ==> the result is the local BOTTOM 729 const Type *bot = bottom_type(); 730 if( (t1 == bot) || (t2 == bot) || 731 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 732 return bot; 733 734 // x/x == 1, we ignore 0/0. 735 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 736 // Does not work for variables because of NaN's 737 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon) 738 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN 739 return TypeD::ONE; 740 741 if( t2 == TypeD::ONE ) 742 return t1; 743 744#if defined(IA32) 745 if (!phase->C->method()->is_strict()) 746 // Can't trust native compilers to properly fold strict double 747 // division with round-to-zero on this platform. 748#endif 749 { 750 // If divisor is a constant and not zero, divide them numbers 751 if( t1->base() == Type::DoubleCon && 752 t2->base() == Type::DoubleCon && 753 t2->getd() != 0.0 ) // could be negative zero 754 return TypeD::make( t1->getd()/t2->getd() ); 755 } 756 757 // If the dividend is a constant zero 758 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 759 // Test TypeF::ZERO is not sufficient as it could be negative zero 760 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 ) 761 return TypeD::ZERO; 762 763 // Otherwise we give up all hope 764 return Type::DOUBLE; 765} 766 767 768//------------------------------isA_Copy--------------------------------------- 769// Dividing by self is 1. 770// If the divisor is 1, we are an identity on the dividend. 771Node *DivDNode::Identity( PhaseTransform *phase ) { 772 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this; 773} 774 775//------------------------------Idealize--------------------------------------- 776Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) { 777 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 778 // Don't bother trying to transform a dead node 779 if( in(0) && in(0)->is_top() ) return NULL; 780 781 const Type *t2 = phase->type( in(2) ); 782 if( t2 == TypeD::ONE ) // Identity? 783 return NULL; // Skip it 784 785 const TypeD *td = t2->isa_double_constant(); 786 if( !td ) return NULL; 787 if( td->base() != Type::DoubleCon ) return NULL; 788 789 // Check for out of range values 790 if( td->is_nan() || !td->is_finite() ) return NULL; 791 792 // Get the value 793 double d = td->getd(); 794 int exp; 795 796 // Only for special case of dividing by a power of 2 797 if( frexp(d, &exp) != 0.5 ) return NULL; 798 799 // Limit the range of acceptable exponents 800 if( exp < -1021 || exp > 1022 ) return NULL; 801 802 // Compute the reciprocal 803 double reciprocal = 1.0 / d; 804 805 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); 806 807 // return multiplication by the reciprocal 808 return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal)))); 809} 810 811//============================================================================= 812//------------------------------Idealize--------------------------------------- 813Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) { 814 // Check for dead control input 815 if( in(0) && remove_dead_region(phase, can_reshape) ) return this; 816 // Don't bother trying to transform a dead node 817 if( in(0) && in(0)->is_top() ) return NULL; 818 819 // Get the modulus 820 const Type *t = phase->type( in(2) ); 821 if( t == Type::TOP ) return NULL; 822 const TypeInt *ti = t->is_int(); 823 824 // Check for useless control input 825 // Check for excluding mod-zero case 826 if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) { 827 set_req(0, NULL); // Yank control input 828 return this; 829 } 830 831 // See if we are MOD'ing by 2^k or 2^k-1. 832 if( !ti->is_con() ) return NULL; 833 jint con = ti->get_con(); 834 835 Node *hook = new (phase->C, 1) Node(1); 836 837 // First, special check for modulo 2^k-1 838 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) { 839 uint k = exact_log2(con+1); // Extract k 840 841 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details. 842 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*/}; 843 int trip_count = 1; 844 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; 845 846 // If the unroll factor is not too large, and if conditional moves are 847 // ok, then use this case 848 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) { 849 Node *x = in(1); // Value being mod'd 850 Node *divisor = in(2); // Also is mask 851 852 hook->init_req(0, x); // Add a use to x to prevent him from dying 853 // Generate code to reduce X rapidly to nearly 2^k-1. 854 for( int i = 0; i < trip_count; i++ ) { 855 Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) ); 856 Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed 857 x = phase->transform( new (phase->C, 3) AddINode(xh,xl) ); 858 hook->set_req(0, x); 859 } 860 861 // Generate sign-fixup code. Was original value positive? 862 // int hack_res = (i >= 0) ? divisor : 1; 863 Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) ); 864 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) ); 865 Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) ); 866 // if( x >= hack_res ) x -= divisor; 867 Node *sub = phase->transform( new (phase->C, 3) SubINode( x, divisor ) ); 868 Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) ); 869 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) ); 870 // Convention is to not transform the return value of an Ideal 871 // since Ideal is expected to return a modified 'this' or a new node. 872 Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT); 873 // cmov2 is now the mod 874 875 // Now remove the bogus extra edges used to keep things alive 876 if (can_reshape) { 877 phase->is_IterGVN()->remove_dead_node(hook); 878 } else { 879 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 880 } 881 return cmov2; 882 } 883 } 884 885 // Fell thru, the unroll case is not appropriate. Transform the modulo 886 // into a long multiply/int multiply/subtract case 887 888 // Cannot handle mod 0, and min_jint isn't handled by the transform 889 if( con == 0 || con == min_jint ) return NULL; 890 891 // Get the absolute value of the constant; at this point, we can use this 892 jint pos_con = (con >= 0) ? con : -con; 893 894 // integer Mod 1 is always 0 895 if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO); 896 897 int log2_con = -1; 898 899 // If this is a power of two, they maybe we can mask it 900 if( is_power_of_2(pos_con) ) { 901 log2_con = log2_intptr((intptr_t)pos_con); 902 903 const Type *dt = phase->type(in(1)); 904 const TypeInt *dti = dt->isa_int(); 905 906 // See if this can be masked, if the dividend is non-negative 907 if( dti && dti->_lo >= 0 ) 908 return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) ); 909 } 910 911 // Save in(1) so that it cannot be changed or deleted 912 hook->init_req(0, in(1)); 913 914 // Divide using the transform from DivI to MulL 915 Node *result = transform_int_divide( phase, in(1), pos_con ); 916 if (result != NULL) { 917 Node *divide = phase->transform(result); 918 919 // Re-multiply, using a shift if this is a power of two 920 Node *mult = NULL; 921 922 if( log2_con >= 0 ) 923 mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) ); 924 else 925 mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) ); 926 927 // Finally, subtract the multiplied divided value from the original 928 result = new (phase->C, 3) SubINode( in(1), mult ); 929 } 930 931 // Now remove the bogus extra edges used to keep things alive 932 if (can_reshape) { 933 phase->is_IterGVN()->remove_dead_node(hook); 934 } else { 935 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 936 } 937 938 // return the value 939 return result; 940} 941 942//------------------------------Value------------------------------------------ 943const Type *ModINode::Value( PhaseTransform *phase ) const { 944 // Either input is TOP ==> the result is TOP 945 const Type *t1 = phase->type( in(1) ); 946 const Type *t2 = phase->type( in(2) ); 947 if( t1 == Type::TOP ) return Type::TOP; 948 if( t2 == Type::TOP ) return Type::TOP; 949 950 // We always generate the dynamic check for 0. 951 // 0 MOD X is 0 952 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; 953 // X MOD X is 0 954 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO; 955 956 // Either input is BOTTOM ==> the result is the local BOTTOM 957 const Type *bot = bottom_type(); 958 if( (t1 == bot) || (t2 == bot) || 959 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 960 return bot; 961 962 const TypeInt *i1 = t1->is_int(); 963 const TypeInt *i2 = t2->is_int(); 964 if( !i1->is_con() || !i2->is_con() ) { 965 if( i1->_lo >= 0 && i2->_lo >= 0 ) 966 return TypeInt::POS; 967 // If both numbers are not constants, we know little. 968 return TypeInt::INT; 969 } 970 // Mod by zero? Throw exception at runtime! 971 if( !i2->get_con() ) return TypeInt::POS; 972 973 // We must be modulo'ing 2 float constants. 974 // Check for min_jint % '-1', result is defined to be '0'. 975 if( i1->get_con() == min_jint && i2->get_con() == -1 ) 976 return TypeInt::ZERO; 977 978 return TypeInt::make( i1->get_con() % i2->get_con() ); 979} 980 981 982//============================================================================= 983//------------------------------Idealize--------------------------------------- 984Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 985 // Check for dead control input 986 if( in(0) && remove_dead_region(phase, can_reshape) ) return this; 987 // Don't bother trying to transform a dead node 988 if( in(0) && in(0)->is_top() ) return NULL; 989 990 // Get the modulus 991 const Type *t = phase->type( in(2) ); 992 if( t == Type::TOP ) return NULL; 993 const TypeLong *tl = t->is_long(); 994 995 // Check for useless control input 996 // Check for excluding mod-zero case 997 if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) { 998 set_req(0, NULL); // Yank control input 999 return this; 1000 } 1001 1002 // See if we are MOD'ing by 2^k or 2^k-1. 1003 if( !tl->is_con() ) return NULL; 1004 jlong con = tl->get_con(); 1005 1006 Node *hook = new (phase->C, 1) Node(1); 1007 1008 // Expand mod 1009 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) { 1010 uint k = exact_log2_long(con+1); // Extract k 1011 1012 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details. 1013 // Used to help a popular random number generator which does a long-mod 1014 // of 2^31-1 and shows up in SpecJBB and SciMark. 1015 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*/}; 1016 int trip_count = 1; 1017 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; 1018 1019 // If the unroll factor is not too large, and if conditional moves are 1020 // ok, then use this case 1021 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) { 1022 Node *x = in(1); // Value being mod'd 1023 Node *divisor = in(2); // Also is mask 1024 1025 hook->init_req(0, x); // Add a use to x to prevent him from dying 1026 // Generate code to reduce X rapidly to nearly 2^k-1. 1027 for( int i = 0; i < trip_count; i++ ) { 1028 Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) ); 1029 Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed 1030 x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) ); 1031 hook->set_req(0, x); // Add a use to x to prevent him from dying 1032 } 1033 1034 // Generate sign-fixup code. Was original value positive? 1035 // long hack_res = (i >= 0) ? divisor : CONST64(1); 1036 Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) ); 1037 Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) ); 1038 Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) ); 1039 // if( x >= hack_res ) x -= divisor; 1040 Node *sub = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) ); 1041 Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) ); 1042 Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) ); 1043 // Convention is to not transform the return value of an Ideal 1044 // since Ideal is expected to return a modified 'this' or a new node. 1045 Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG); 1046 // cmov2 is now the mod 1047 1048 // Now remove the bogus extra edges used to keep things alive 1049 if (can_reshape) { 1050 phase->is_IterGVN()->remove_dead_node(hook); 1051 } else { 1052 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 1053 } 1054 return cmov2; 1055 } 1056 } 1057 1058 // Fell thru, the unroll case is not appropriate. Transform the modulo 1059 // into a long multiply/int multiply/subtract case 1060 1061 // Cannot handle mod 0, and min_jint isn't handled by the transform 1062 if( con == 0 || con == min_jlong ) return NULL; 1063 1064 // Get the absolute value of the constant; at this point, we can use this 1065 jlong pos_con = (con >= 0) ? con : -con; 1066 1067 // integer Mod 1 is always 0 1068 if( pos_con == 1 ) return new (phase->C, 1) ConLNode(TypeLong::ZERO); 1069 1070 int log2_con = -1; 1071 1072 // If this is a power of two, then maybe we can mask it 1073 if( is_power_of_2_long(pos_con) ) { 1074 log2_con = log2_long(pos_con); 1075 1076 const Type *dt = phase->type(in(1)); 1077 const TypeLong *dtl = dt->isa_long(); 1078 1079 // See if this can be masked, if the dividend is non-negative 1080 if( dtl && dtl->_lo >= 0 ) 1081 return ( new (phase->C, 3) AndLNode( in(1), phase->longcon( pos_con-1 ) ) ); 1082 } 1083 1084 // Save in(1) so that it cannot be changed or deleted 1085 hook->init_req(0, in(1)); 1086 1087 // Divide using the transform from DivI to MulL 1088 Node *result = transform_long_divide( phase, in(1), pos_con ); 1089 if (result != NULL) { 1090 Node *divide = phase->transform(result); 1091 1092 // Re-multiply, using a shift if this is a power of two 1093 Node *mult = NULL; 1094 1095 if( log2_con >= 0 ) 1096 mult = phase->transform( new (phase->C, 3) LShiftLNode( divide, phase->intcon( log2_con ) ) ); 1097 else 1098 mult = phase->transform( new (phase->C, 3) MulLNode( divide, phase->longcon( pos_con ) ) ); 1099 1100 // Finally, subtract the multiplied divided value from the original 1101 result = new (phase->C, 3) SubLNode( in(1), mult ); 1102 } 1103 1104 // Now remove the bogus extra edges used to keep things alive 1105 if (can_reshape) { 1106 phase->is_IterGVN()->remove_dead_node(hook); 1107 } else { 1108 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 1109 } 1110 1111 // return the value 1112 return result; 1113} 1114 1115//------------------------------Value------------------------------------------ 1116const Type *ModLNode::Value( PhaseTransform *phase ) const { 1117 // Either input is TOP ==> the result is TOP 1118 const Type *t1 = phase->type( in(1) ); 1119 const Type *t2 = phase->type( in(2) ); 1120 if( t1 == Type::TOP ) return Type::TOP; 1121 if( t2 == Type::TOP ) return Type::TOP; 1122 1123 // We always generate the dynamic check for 0. 1124 // 0 MOD X is 0 1125 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; 1126 // X MOD X is 0 1127 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO; 1128 1129 // Either input is BOTTOM ==> the result is the local BOTTOM 1130 const Type *bot = bottom_type(); 1131 if( (t1 == bot) || (t2 == bot) || 1132 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1133 return bot; 1134 1135 const TypeLong *i1 = t1->is_long(); 1136 const TypeLong *i2 = t2->is_long(); 1137 if( !i1->is_con() || !i2->is_con() ) { 1138 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) ) 1139 return TypeLong::POS; 1140 // If both numbers are not constants, we know little. 1141 return TypeLong::LONG; 1142 } 1143 // Mod by zero? Throw exception at runtime! 1144 if( !i2->get_con() ) return TypeLong::POS; 1145 1146 // We must be modulo'ing 2 float constants. 1147 // Check for min_jint % '-1', result is defined to be '0'. 1148 if( i1->get_con() == min_jlong && i2->get_con() == -1 ) 1149 return TypeLong::ZERO; 1150 1151 return TypeLong::make( i1->get_con() % i2->get_con() ); 1152} 1153 1154 1155//============================================================================= 1156//------------------------------Value------------------------------------------ 1157const Type *ModFNode::Value( PhaseTransform *phase ) const { 1158 // Either input is TOP ==> the result is TOP 1159 const Type *t1 = phase->type( in(1) ); 1160 const Type *t2 = phase->type( in(2) ); 1161 if( t1 == Type::TOP ) return Type::TOP; 1162 if( t2 == Type::TOP ) return Type::TOP; 1163 1164 // Either input is BOTTOM ==> the result is the local BOTTOM 1165 const Type *bot = bottom_type(); 1166 if( (t1 == bot) || (t2 == bot) || 1167 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1168 return bot; 1169 1170 // If either number is not a constant, we know nothing. 1171 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) { 1172 return Type::FLOAT; // note: x%x can be either NaN or 0 1173 } 1174 1175 float f1 = t1->getf(); 1176 float f2 = t2->getf(); 1177 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1 1178 jint x2 = jint_cast(f2); 1179 1180 // If either is a NaN, return an input NaN 1181 if (g_isnan(f1)) return t1; 1182 if (g_isnan(f2)) return t2; 1183 1184 // If an operand is infinity or the divisor is +/- zero, punt. 1185 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint) 1186 return Type::FLOAT; 1187 1188 // We must be modulo'ing 2 float constants. 1189 // Make sure that the sign of the fmod is equal to the sign of the dividend 1190 jint xr = jint_cast(fmod(f1, f2)); 1191 if ((x1 ^ xr) < 0) { 1192 xr ^= min_jint; 1193 } 1194 1195 return TypeF::make(jfloat_cast(xr)); 1196} 1197 1198 1199//============================================================================= 1200//------------------------------Value------------------------------------------ 1201const Type *ModDNode::Value( PhaseTransform *phase ) const { 1202 // Either input is TOP ==> the result is TOP 1203 const Type *t1 = phase->type( in(1) ); 1204 const Type *t2 = phase->type( in(2) ); 1205 if( t1 == Type::TOP ) return Type::TOP; 1206 if( t2 == Type::TOP ) return Type::TOP; 1207 1208 // Either input is BOTTOM ==> the result is the local BOTTOM 1209 const Type *bot = bottom_type(); 1210 if( (t1 == bot) || (t2 == bot) || 1211 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1212 return bot; 1213 1214 // If either number is not a constant, we know nothing. 1215 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) { 1216 return Type::DOUBLE; // note: x%x can be either NaN or 0 1217 } 1218 1219 double f1 = t1->getd(); 1220 double f2 = t2->getd(); 1221 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1 1222 jlong x2 = jlong_cast(f2); 1223 1224 // If either is a NaN, return an input NaN 1225 if (g_isnan(f1)) return t1; 1226 if (g_isnan(f2)) return t2; 1227 1228 // If an operand is infinity or the divisor is +/- zero, punt. 1229 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong) 1230 return Type::DOUBLE; 1231 1232 // We must be modulo'ing 2 double constants. 1233 // Make sure that the sign of the fmod is equal to the sign of the dividend 1234 jlong xr = jlong_cast(fmod(f1, f2)); 1235 if ((x1 ^ xr) < 0) { 1236 xr ^= min_jlong; 1237 } 1238 1239 return TypeD::make(jdouble_cast(xr)); 1240} 1241 1242//============================================================================= 1243 1244DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) { 1245 init_req(0, c); 1246 init_req(1, dividend); 1247 init_req(2, divisor); 1248} 1249 1250//------------------------------make------------------------------------------ 1251DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) { 1252 Node* n = div_or_mod; 1253 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI, 1254 "only div or mod input pattern accepted"); 1255 1256 DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2)); 1257 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num); 1258 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num); 1259 return divmod; 1260} 1261 1262//------------------------------make------------------------------------------ 1263DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) { 1264 Node* n = div_or_mod; 1265 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL, 1266 "only div or mod input pattern accepted"); 1267 1268 DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2)); 1269 Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num); 1270 Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num); 1271 return divmod; 1272} 1273 1274//------------------------------match------------------------------------------ 1275// return result(s) along with their RegMask info 1276Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) { 1277 uint ideal_reg = proj->ideal_reg(); 1278 RegMask rm; 1279 if (proj->_con == div_proj_num) { 1280 rm = match->divI_proj_mask(); 1281 } else { 1282 assert(proj->_con == mod_proj_num, "must be div or mod projection"); 1283 rm = match->modI_proj_mask(); 1284 } 1285 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg); 1286} 1287 1288 1289//------------------------------match------------------------------------------ 1290// return result(s) along with their RegMask info 1291Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) { 1292 uint ideal_reg = proj->ideal_reg(); 1293 RegMask rm; 1294 if (proj->_con == div_proj_num) { 1295 rm = match->divL_proj_mask(); 1296 } else { 1297 assert(proj->_con == mod_proj_num, "must be div or mod projection"); 1298 rm = match->modL_proj_mask(); 1299 } 1300 return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg); 1301} 1302