1 /* 2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "memory/allocation.inline.hpp" 27 #include "opto/addnode.hpp" 28 #include "opto/connode.hpp" 29 #include "opto/convertnode.hpp" 30 #include "opto/divnode.hpp" 31 #include "opto/machnode.hpp" 32 #include "opto/movenode.hpp" 33 #include "opto/matcher.hpp" 34 #include "opto/mulnode.hpp" 35 #include "opto/phaseX.hpp" 36 #include "opto/subnode.hpp" 37 38 // Portions of code courtesy of Clifford Click 39 40 // Optimization - Graph Style 41 42 #include <math.h> 43 44 //----------------------magic_int_divide_constants----------------------------- 45 // Compute magic multiplier and shift constant for converting a 32 bit divide 46 // by constant into a multiply/shift/add series. Return false if calculations 47 // fail. 48 // 49 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with 50 // minor type name and parameter changes. 51 static bool magic_int_divide_constants(jint d, jint &M, jint &s) { 52 int32_t p; 53 uint32_t ad, anc, delta, q1, r1, q2, r2, t; 54 const uint32_t two31 = 0x80000000L; // 2**31. 55 56 ad = ABS(d); 57 if (d == 0 || d == 1) return false; 58 t = two31 + ((uint32_t)d >> 31); 59 anc = t - 1 - t%ad; // Absolute value of nc. 60 p = 31; // Init. p. 61 q1 = two31/anc; // Init. q1 = 2**p/|nc|. 62 r1 = two31 - q1*anc; // Init. r1 = rem(2**p, |nc|). 63 q2 = two31/ad; // Init. q2 = 2**p/|d|. 64 r2 = two31 - q2*ad; // Init. r2 = rem(2**p, |d|). 65 do { 66 p = p + 1; 67 q1 = 2*q1; // Update q1 = 2**p/|nc|. 68 r1 = 2*r1; // Update r1 = rem(2**p, |nc|). 69 if (r1 >= anc) { // (Must be an unsigned 70 q1 = q1 + 1; // comparison here). 71 r1 = r1 - anc; 72 } 73 q2 = 2*q2; // Update q2 = 2**p/|d|. 74 r2 = 2*r2; // Update r2 = rem(2**p, |d|). 75 if (r2 >= ad) { // (Must be an unsigned 76 q2 = q2 + 1; // comparison here). 77 r2 = r2 - ad; 78 } 79 delta = ad - r2; 80 } while (q1 < delta || (q1 == delta && r1 == 0)); 81 82 M = q2 + 1; 83 if (d < 0) M = -M; // Magic number and 84 s = p - 32; // shift amount to return. 85 86 return true; 87 } 88 89 //--------------------------transform_int_divide------------------------------- 90 // Convert a division by constant divisor into an alternate Ideal graph. 91 // Return NULL if no transformation occurs. 92 static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) { 93 94 // Check for invalid divisors 95 assert( divisor != 0 && divisor != min_jint, 96 "bad divisor for transforming to long multiply" ); 97 98 bool d_pos = divisor >= 0; 99 jint d = d_pos ? divisor : -divisor; 100 const int N = 32; 101 102 // Result 103 Node *q = NULL; 104 105 if (d == 1) { 106 // division by +/- 1 107 if (!d_pos) { 108 // Just negate the value 109 q = new SubINode(phase->intcon(0), dividend); 110 } 111 } else if ( is_power_of_2(d) ) { 112 // division by +/- a power of 2 113 114 // See if we can simply do a shift without rounding 115 bool needs_rounding = true; 116 const Type *dt = phase->type(dividend); 117 const TypeInt *dti = dt->isa_int(); 118 if (dti && dti->_lo >= 0) { 119 // we don't need to round a positive dividend 120 needs_rounding = false; 121 } else if( dividend->Opcode() == Op_AndI ) { 122 // An AND mask of sufficient size clears the low bits and 123 // I can avoid rounding. 124 const TypeInt *andconi_t = phase->type( dividend->in(2) )->isa_int(); 125 if( andconi_t && andconi_t->is_con() ) { 126 jint andconi = andconi_t->get_con(); 127 if( andconi < 0 && is_power_of_2(-andconi) && (-andconi) >= d ) { 128 if( (-andconi) == d ) // Remove AND if it clears bits which will be shifted 129 dividend = dividend->in(1); 130 needs_rounding = false; 131 } 132 } 133 } 134 135 // Add rounding to the shift to handle the sign bit 136 int l = log2_intptr(d-1)+1; 137 if (needs_rounding) { 138 // Divide-by-power-of-2 can be made into a shift, but you have to do 139 // more math for the rounding. You need to add 0 for positive 140 // numbers, and "i-1" for negative numbers. Example: i=4, so the 141 // shift is by 2. You need to add 3 to negative dividends and 0 to 142 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1, 143 // (-2+3)>>2 becomes 0, etc. 144 145 // Compute 0 or -1, based on sign bit 146 Node *sign = phase->transform(new RShiftINode(dividend, phase->intcon(N - 1))); 147 // Mask sign bit to the low sign bits 148 Node *round = phase->transform(new URShiftINode(sign, phase->intcon(N - l))); 149 // Round up before shifting 150 dividend = phase->transform(new AddINode(dividend, round)); 151 } 152 153 // Shift for division 154 q = new RShiftINode(dividend, phase->intcon(l)); 155 156 if (!d_pos) { 157 q = new SubINode(phase->intcon(0), phase->transform(q)); 158 } 159 } else { 160 // Attempt the jint constant divide -> multiply transform found in 161 // "Division by Invariant Integers using Multiplication" 162 // by Granlund and Montgomery 163 // See also "Hacker's Delight", chapter 10 by Warren. 164 165 jint magic_const; 166 jint shift_const; 167 if (magic_int_divide_constants(d, magic_const, shift_const)) { 168 Node *magic = phase->longcon(magic_const); 169 Node *dividend_long = phase->transform(new ConvI2LNode(dividend)); 170 171 // Compute the high half of the dividend x magic multiplication 172 Node *mul_hi = phase->transform(new MulLNode(dividend_long, magic)); 173 174 if (magic_const < 0) { 175 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(N))); 176 mul_hi = phase->transform(new ConvL2INode(mul_hi)); 177 178 // The magic multiplier is too large for a 32 bit constant. We've adjusted 179 // it down by 2^32, but have to add 1 dividend back in after the multiplication. 180 // This handles the "overflow" case described by Granlund and Montgomery. 181 mul_hi = phase->transform(new AddINode(dividend, mul_hi)); 182 183 // Shift over the (adjusted) mulhi 184 if (shift_const != 0) { 185 mul_hi = phase->transform(new RShiftINode(mul_hi, phase->intcon(shift_const))); 186 } 187 } else { 188 // No add is required, we can merge the shifts together. 189 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(N + shift_const))); 190 mul_hi = phase->transform(new ConvL2INode(mul_hi)); 191 } 192 193 // Get a 0 or -1 from the sign of the dividend. 194 Node *addend0 = mul_hi; 195 Node *addend1 = phase->transform(new RShiftINode(dividend, phase->intcon(N-1))); 196 197 // If the divisor is negative, swap the order of the input addends; 198 // this has the effect of negating the quotient. 199 if (!d_pos) { 200 Node *temp = addend0; addend0 = addend1; addend1 = temp; 201 } 202 203 // Adjust the final quotient by subtracting -1 (adding 1) 204 // from the mul_hi. 205 q = new SubINode(addend0, addend1); 206 } 207 } 208 209 return q; 210 } 211 212 //---------------------magic_long_divide_constants----------------------------- 213 // Compute magic multiplier and shift constant for converting a 64 bit divide 214 // by constant into a multiply/shift/add series. Return false if calculations 215 // fail. 216 // 217 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with 218 // minor type name and parameter changes. Adjusted to 64 bit word width. 219 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) { 220 int64_t p; 221 uint64_t ad, anc, delta, q1, r1, q2, r2, t; 222 const uint64_t two63 = UCONST64(0x8000000000000000); // 2**63. 223 224 ad = ABS(d); 225 if (d == 0 || d == 1) return false; 226 t = two63 + ((uint64_t)d >> 63); 227 anc = t - 1 - t%ad; // Absolute value of nc. 228 p = 63; // Init. p. 229 q1 = two63/anc; // Init. q1 = 2**p/|nc|. 230 r1 = two63 - q1*anc; // Init. r1 = rem(2**p, |nc|). 231 q2 = two63/ad; // Init. q2 = 2**p/|d|. 232 r2 = two63 - q2*ad; // Init. r2 = rem(2**p, |d|). 233 do { 234 p = p + 1; 235 q1 = 2*q1; // Update q1 = 2**p/|nc|. 236 r1 = 2*r1; // Update r1 = rem(2**p, |nc|). 237 if (r1 >= anc) { // (Must be an unsigned 238 q1 = q1 + 1; // comparison here). 239 r1 = r1 - anc; 240 } 241 q2 = 2*q2; // Update q2 = 2**p/|d|. 242 r2 = 2*r2; // Update r2 = rem(2**p, |d|). 243 if (r2 >= ad) { // (Must be an unsigned 244 q2 = q2 + 1; // comparison here). 245 r2 = r2 - ad; 246 } 247 delta = ad - r2; 248 } while (q1 < delta || (q1 == delta && r1 == 0)); 249 250 M = q2 + 1; 251 if (d < 0) M = -M; // Magic number and 252 s = p - 64; // shift amount to return. 253 254 return true; 255 } 256 257 //---------------------long_by_long_mulhi-------------------------------------- 258 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication 259 static Node* long_by_long_mulhi(PhaseGVN* phase, Node* dividend, jlong magic_const) { 260 // If the architecture supports a 64x64 mulhi, there is 261 // no need to synthesize it in ideal nodes. 262 if (Matcher::has_match_rule(Op_MulHiL)) { 263 Node* v = phase->longcon(magic_const); 264 return new MulHiLNode(dividend, v); 265 } 266 267 // Taken from Hacker's Delight, Fig. 8-2. Multiply high signed. 268 // (http://www.hackersdelight.org/HDcode/mulhs.c) 269 // 270 // int mulhs(int u, int v) { 271 // unsigned u0, v0, w0; 272 // int u1, v1, w1, w2, t; 273 // 274 // u0 = u & 0xFFFF; u1 = u >> 16; 275 // v0 = v & 0xFFFF; v1 = v >> 16; 276 // w0 = u0*v0; 277 // t = u1*v0 + (w0 >> 16); 278 // w1 = t & 0xFFFF; 279 // w2 = t >> 16; 280 // w1 = u0*v1 + w1; 281 // return u1*v1 + w2 + (w1 >> 16); 282 // } 283 // 284 // Note: The version above is for 32x32 multiplications, while the 285 // following inline comments are adapted to 64x64. 286 287 const int N = 64; 288 289 // Dummy node to keep intermediate nodes alive during construction 290 Node* hook = new Node(4); 291 292 // u0 = u & 0xFFFFFFFF; u1 = u >> 32; 293 Node* u0 = phase->transform(new AndLNode(dividend, phase->longcon(0xFFFFFFFF))); 294 Node* u1 = phase->transform(new RShiftLNode(dividend, phase->intcon(N / 2))); 295 hook->init_req(0, u0); 296 hook->init_req(1, u1); 297 298 // v0 = v & 0xFFFFFFFF; v1 = v >> 32; 299 Node* v0 = phase->longcon(magic_const & 0xFFFFFFFF); 300 Node* v1 = phase->longcon(magic_const >> (N / 2)); 301 302 // w0 = u0*v0; 303 Node* w0 = phase->transform(new MulLNode(u0, v0)); 304 305 // t = u1*v0 + (w0 >> 32); 306 Node* u1v0 = phase->transform(new MulLNode(u1, v0)); 307 Node* temp = phase->transform(new URShiftLNode(w0, phase->intcon(N / 2))); 308 Node* t = phase->transform(new AddLNode(u1v0, temp)); 309 hook->init_req(2, t); 310 311 // w1 = t & 0xFFFFFFFF; 312 Node* w1 = phase->transform(new AndLNode(t, phase->longcon(0xFFFFFFFF))); 313 hook->init_req(3, w1); 314 315 // w2 = t >> 32; 316 Node* w2 = phase->transform(new RShiftLNode(t, phase->intcon(N / 2))); 317 318 // w1 = u0*v1 + w1; 319 Node* u0v1 = phase->transform(new MulLNode(u0, v1)); 320 w1 = phase->transform(new AddLNode(u0v1, w1)); 321 322 // return u1*v1 + w2 + (w1 >> 32); 323 Node* u1v1 = phase->transform(new MulLNode(u1, v1)); 324 Node* temp1 = phase->transform(new AddLNode(u1v1, w2)); 325 Node* temp2 = phase->transform(new RShiftLNode(w1, phase->intcon(N / 2))); 326 327 // Remove the bogus extra edges used to keep things alive 328 PhaseIterGVN* igvn = phase->is_IterGVN(); 329 if (igvn != NULL) { 330 igvn->remove_dead_node(hook); 331 } else { 332 for (int i = 0; i < 4; i++) { 333 hook->set_req(i, NULL); 334 } 335 } 336 337 return new AddLNode(temp1, temp2); 338 } 339 340 341 //--------------------------transform_long_divide------------------------------ 342 // Convert a division by constant divisor into an alternate Ideal graph. 343 // Return NULL if no transformation occurs. 344 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) { 345 // Check for invalid divisors 346 assert( divisor != 0L && divisor != min_jlong, 347 "bad divisor for transforming to long multiply" ); 348 349 bool d_pos = divisor >= 0; 350 jlong d = d_pos ? divisor : -divisor; 351 const int N = 64; 352 353 // Result 354 Node *q = NULL; 355 356 if (d == 1) { 357 // division by +/- 1 358 if (!d_pos) { 359 // Just negate the value 360 q = new SubLNode(phase->longcon(0), dividend); 361 } 362 } else if ( is_power_of_2_long(d) ) { 363 364 // division by +/- a power of 2 365 366 // See if we can simply do a shift without rounding 367 bool needs_rounding = true; 368 const Type *dt = phase->type(dividend); 369 const TypeLong *dtl = dt->isa_long(); 370 371 if (dtl && dtl->_lo > 0) { 372 // we don't need to round a positive dividend 373 needs_rounding = false; 374 } else if( dividend->Opcode() == Op_AndL ) { 375 // An AND mask of sufficient size clears the low bits and 376 // I can avoid rounding. 377 const TypeLong *andconl_t = phase->type( dividend->in(2) )->isa_long(); 378 if( andconl_t && andconl_t->is_con() ) { 379 jlong andconl = andconl_t->get_con(); 380 if( andconl < 0 && is_power_of_2_long(-andconl) && (-andconl) >= d ) { 381 if( (-andconl) == d ) // Remove AND if it clears bits which will be shifted 382 dividend = dividend->in(1); 383 needs_rounding = false; 384 } 385 } 386 } 387 388 // Add rounding to the shift to handle the sign bit 389 int l = log2_long(d-1)+1; 390 if (needs_rounding) { 391 // Divide-by-power-of-2 can be made into a shift, but you have to do 392 // more math for the rounding. You need to add 0 for positive 393 // numbers, and "i-1" for negative numbers. Example: i=4, so the 394 // shift is by 2. You need to add 3 to negative dividends and 0 to 395 // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1, 396 // (-2+3)>>2 becomes 0, etc. 397 398 // Compute 0 or -1, based on sign bit 399 Node *sign = phase->transform(new RShiftLNode(dividend, phase->intcon(N - 1))); 400 // Mask sign bit to the low sign bits 401 Node *round = phase->transform(new URShiftLNode(sign, phase->intcon(N - l))); 402 // Round up before shifting 403 dividend = phase->transform(new AddLNode(dividend, round)); 404 } 405 406 // Shift for division 407 q = new RShiftLNode(dividend, phase->intcon(l)); 408 409 if (!d_pos) { 410 q = new SubLNode(phase->longcon(0), phase->transform(q)); 411 } 412 } else if ( !Matcher::use_asm_for_ldiv_by_con(d) ) { // Use hardware DIV instruction when 413 // it is faster than code generated below. 414 // Attempt the jlong constant divide -> multiply transform found in 415 // "Division by Invariant Integers using Multiplication" 416 // by Granlund and Montgomery 417 // See also "Hacker's Delight", chapter 10 by Warren. 418 419 jlong magic_const; 420 jint shift_const; 421 if (magic_long_divide_constants(d, magic_const, shift_const)) { 422 // Compute the high half of the dividend x magic multiplication 423 Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const)); 424 425 // The high half of the 128-bit multiply is computed. 426 if (magic_const < 0) { 427 // The magic multiplier is too large for a 64 bit constant. We've adjusted 428 // it down by 2^64, but have to add 1 dividend back in after the multiplication. 429 // This handles the "overflow" case described by Granlund and Montgomery. 430 mul_hi = phase->transform(new AddLNode(dividend, mul_hi)); 431 } 432 433 // Shift over the (adjusted) mulhi 434 if (shift_const != 0) { 435 mul_hi = phase->transform(new RShiftLNode(mul_hi, phase->intcon(shift_const))); 436 } 437 438 // Get a 0 or -1 from the sign of the dividend. 439 Node *addend0 = mul_hi; 440 Node *addend1 = phase->transform(new RShiftLNode(dividend, phase->intcon(N-1))); 441 442 // If the divisor is negative, swap the order of the input addends; 443 // this has the effect of negating the quotient. 444 if (!d_pos) { 445 Node *temp = addend0; addend0 = addend1; addend1 = temp; 446 } 447 448 // Adjust the final quotient by subtracting -1 (adding 1) 449 // from the mul_hi. 450 q = new SubLNode(addend0, addend1); 451 } 452 } 453 454 return q; 455 } 456 457 //============================================================================= 458 //------------------------------Identity--------------------------------------- 459 // If the divisor is 1, we are an identity on the dividend. 460 Node* DivINode::Identity(PhaseGVN* phase) { 461 return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this; 462 } 463 464 //------------------------------Idealize--------------------------------------- 465 // Divides can be changed to multiplies and/or shifts 466 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) { 467 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 468 // Don't bother trying to transform a dead node 469 if( in(0) && in(0)->is_top() ) return NULL; 470 471 const Type *t = phase->type( in(2) ); 472 if( t == TypeInt::ONE ) // Identity? 473 return NULL; // Skip it 474 475 const TypeInt *ti = t->isa_int(); 476 if( !ti ) return NULL; 477 478 // Check for useless control input 479 // Check for excluding div-zero case 480 if (in(0) && (ti->_hi < 0 || ti->_lo > 0)) { 481 set_req(0, NULL); // Yank control input 482 return this; 483 } 484 485 if( !ti->is_con() ) return NULL; 486 jint i = ti->get_con(); // Get divisor 487 488 if (i == 0) return NULL; // Dividing by zero constant does not idealize 489 490 // Dividing by MININT does not optimize as a power-of-2 shift. 491 if( i == min_jint ) return NULL; 492 493 return transform_int_divide( phase, in(1), i ); 494 } 495 496 //------------------------------Value------------------------------------------ 497 // A DivINode divides its inputs. The third input is a Control input, used to 498 // prevent hoisting the divide above an unsafe test. 499 const Type* DivINode::Value(PhaseGVN* phase) const { 500 // Either input is TOP ==> the result is TOP 501 const Type *t1 = phase->type( in(1) ); 502 const Type *t2 = phase->type( in(2) ); 503 if( t1 == Type::TOP ) return Type::TOP; 504 if( t2 == Type::TOP ) return Type::TOP; 505 506 // x/x == 1 since we always generate the dynamic divisor check for 0. 507 if( phase->eqv( in(1), in(2) ) ) 508 return TypeInt::ONE; 509 510 // Either input is BOTTOM ==> the result is the local BOTTOM 511 const Type *bot = bottom_type(); 512 if( (t1 == bot) || (t2 == bot) || 513 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 514 return bot; 515 516 // Divide the two numbers. We approximate. 517 // If divisor is a constant and not zero 518 const TypeInt *i1 = t1->is_int(); 519 const TypeInt *i2 = t2->is_int(); 520 int widen = MAX2(i1->_widen, i2->_widen); 521 522 if( i2->is_con() && i2->get_con() != 0 ) { 523 int32_t d = i2->get_con(); // Divisor 524 jint lo, hi; 525 if( d >= 0 ) { 526 lo = i1->_lo/d; 527 hi = i1->_hi/d; 528 } else { 529 if( d == -1 && i1->_lo == min_jint ) { 530 // 'min_jint/-1' throws arithmetic exception during compilation 531 lo = min_jint; 532 // do not support holes, 'hi' must go to either min_jint or max_jint: 533 // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint] 534 hi = i1->_hi == min_jint ? min_jint : max_jint; 535 } else { 536 lo = i1->_hi/d; 537 hi = i1->_lo/d; 538 } 539 } 540 return TypeInt::make(lo, hi, widen); 541 } 542 543 // If the dividend is a constant 544 if( i1->is_con() ) { 545 int32_t d = i1->get_con(); 546 if( d < 0 ) { 547 if( d == min_jint ) { 548 // (-min_jint) == min_jint == (min_jint / -1) 549 return TypeInt::make(min_jint, max_jint/2 + 1, widen); 550 } else { 551 return TypeInt::make(d, -d, widen); 552 } 553 } 554 return TypeInt::make(-d, d, widen); 555 } 556 557 // Otherwise we give up all hope 558 return TypeInt::INT; 559 } 560 561 562 //============================================================================= 563 //------------------------------Identity--------------------------------------- 564 // If the divisor is 1, we are an identity on the dividend. 565 Node* DivLNode::Identity(PhaseGVN* phase) { 566 return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this; 567 } 568 569 //------------------------------Idealize--------------------------------------- 570 // Dividing by a power of 2 is a shift. 571 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) { 572 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 573 // Don't bother trying to transform a dead node 574 if( in(0) && in(0)->is_top() ) return NULL; 575 576 const Type *t = phase->type( in(2) ); 577 if( t == TypeLong::ONE ) // Identity? 578 return NULL; // Skip it 579 580 const TypeLong *tl = t->isa_long(); 581 if( !tl ) return NULL; 582 583 // Check for useless control input 584 // Check for excluding div-zero case 585 if (in(0) && (tl->_hi < 0 || tl->_lo > 0)) { 586 set_req(0, NULL); // Yank control input 587 return this; 588 } 589 590 if( !tl->is_con() ) return NULL; 591 jlong l = tl->get_con(); // Get divisor 592 593 if (l == 0) return NULL; // Dividing by zero constant does not idealize 594 595 // Dividing by MINLONG does not optimize as a power-of-2 shift. 596 if( l == min_jlong ) return NULL; 597 598 return transform_long_divide( phase, in(1), l ); 599 } 600 601 //------------------------------Value------------------------------------------ 602 // A DivLNode divides its inputs. The third input is a Control input, used to 603 // prevent hoisting the divide above an unsafe test. 604 const Type* DivLNode::Value(PhaseGVN* phase) const { 605 // Either input is TOP ==> the result is TOP 606 const Type *t1 = phase->type( in(1) ); 607 const Type *t2 = phase->type( in(2) ); 608 if( t1 == Type::TOP ) return Type::TOP; 609 if( t2 == Type::TOP ) return Type::TOP; 610 611 // x/x == 1 since we always generate the dynamic divisor check for 0. 612 if( phase->eqv( in(1), in(2) ) ) 613 return TypeLong::ONE; 614 615 // Either input is BOTTOM ==> the result is the local BOTTOM 616 const Type *bot = bottom_type(); 617 if( (t1 == bot) || (t2 == bot) || 618 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 619 return bot; 620 621 // Divide the two numbers. We approximate. 622 // If divisor is a constant and not zero 623 const TypeLong *i1 = t1->is_long(); 624 const TypeLong *i2 = t2->is_long(); 625 int widen = MAX2(i1->_widen, i2->_widen); 626 627 if( i2->is_con() && i2->get_con() != 0 ) { 628 jlong d = i2->get_con(); // Divisor 629 jlong lo, hi; 630 if( d >= 0 ) { 631 lo = i1->_lo/d; 632 hi = i1->_hi/d; 633 } else { 634 if( d == CONST64(-1) && i1->_lo == min_jlong ) { 635 // 'min_jlong/-1' throws arithmetic exception during compilation 636 lo = min_jlong; 637 // do not support holes, 'hi' must go to either min_jlong or max_jlong: 638 // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong] 639 hi = i1->_hi == min_jlong ? min_jlong : max_jlong; 640 } else { 641 lo = i1->_hi/d; 642 hi = i1->_lo/d; 643 } 644 } 645 return TypeLong::make(lo, hi, widen); 646 } 647 648 // If the dividend is a constant 649 if( i1->is_con() ) { 650 jlong d = i1->get_con(); 651 if( d < 0 ) { 652 if( d == min_jlong ) { 653 // (-min_jlong) == min_jlong == (min_jlong / -1) 654 return TypeLong::make(min_jlong, max_jlong/2 + 1, widen); 655 } else { 656 return TypeLong::make(d, -d, widen); 657 } 658 } 659 return TypeLong::make(-d, d, widen); 660 } 661 662 // Otherwise we give up all hope 663 return TypeLong::LONG; 664 } 665 666 667 //============================================================================= 668 //------------------------------Value------------------------------------------ 669 // An DivFNode divides its inputs. The third input is a Control input, used to 670 // prevent hoisting the divide above an unsafe test. 671 const Type* DivFNode::Value(PhaseGVN* phase) const { 672 // Either input is TOP ==> the result is TOP 673 const Type *t1 = phase->type( in(1) ); 674 const Type *t2 = phase->type( in(2) ); 675 if( t1 == Type::TOP ) return Type::TOP; 676 if( t2 == Type::TOP ) return Type::TOP; 677 678 // Either input is BOTTOM ==> the result is the local BOTTOM 679 const Type *bot = bottom_type(); 680 if( (t1 == bot) || (t2 == bot) || 681 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 682 return bot; 683 684 // x/x == 1, we ignore 0/0. 685 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 686 // Does not work for variables because of NaN's 687 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon) 688 if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN 689 return TypeF::ONE; 690 691 if( t2 == TypeF::ONE ) 692 return t1; 693 694 // If divisor is a constant and not zero, divide them numbers 695 if( t1->base() == Type::FloatCon && 696 t2->base() == Type::FloatCon && 697 t2->getf() != 0.0 ) // could be negative zero 698 return TypeF::make( t1->getf()/t2->getf() ); 699 700 // If the dividend is a constant zero 701 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 702 // Test TypeF::ZERO is not sufficient as it could be negative zero 703 704 if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 ) 705 return TypeF::ZERO; 706 707 // Otherwise we give up all hope 708 return Type::FLOAT; 709 } 710 711 //------------------------------isA_Copy--------------------------------------- 712 // Dividing by self is 1. 713 // If the divisor is 1, we are an identity on the dividend. 714 Node* DivFNode::Identity(PhaseGVN* phase) { 715 return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this; 716 } 717 718 719 //------------------------------Idealize--------------------------------------- 720 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 721 if (in(0) && remove_dead_region(phase, can_reshape)) return this; 722 // Don't bother trying to transform a dead node 723 if( in(0) && in(0)->is_top() ) return NULL; 724 725 const Type *t2 = phase->type( in(2) ); 726 if( t2 == TypeF::ONE ) // Identity? 727 return NULL; // Skip it 728 729 const TypeF *tf = t2->isa_float_constant(); 730 if( !tf ) return NULL; 731 if( tf->base() != Type::FloatCon ) return NULL; 732 733 // Check for out of range values 734 if( tf->is_nan() || !tf->is_finite() ) return NULL; 735 736 // Get the value 737 float f = tf->getf(); 738 int exp; 739 740 // Only for special case of dividing by a power of 2 741 if( frexp((double)f, &exp) != 0.5 ) return NULL; 742 743 // Limit the range of acceptable exponents 744 if( exp < -126 || exp > 126 ) return NULL; 745 746 // Compute the reciprocal 747 float reciprocal = ((float)1.0) / f; 748 749 assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); 750 751 // return multiplication by the reciprocal 752 return (new MulFNode(in(1), phase->makecon(TypeF::make(reciprocal)))); 753 } 754 755 //============================================================================= 756 //------------------------------Value------------------------------------------ 757 // An DivDNode divides its inputs. The third input is a Control input, used to 758 // prevent hoisting the divide above an unsafe test. 759 const Type* DivDNode::Value(PhaseGVN* phase) const { 760 // Either input is TOP ==> the result is TOP 761 const Type *t1 = phase->type( in(1) ); 762 const Type *t2 = phase->type( in(2) ); 763 if( t1 == Type::TOP ) return Type::TOP; 764 if( t2 == Type::TOP ) return Type::TOP; 765 766 // Either input is BOTTOM ==> the result is the local BOTTOM 767 const Type *bot = bottom_type(); 768 if( (t1 == bot) || (t2 == bot) || 769 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 770 return bot; 771 772 // x/x == 1, we ignore 0/0. 773 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 774 // Does not work for variables because of NaN's 775 if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon) 776 if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN 777 return TypeD::ONE; 778 779 if( t2 == TypeD::ONE ) 780 return t1; 781 782 #if defined(IA32) 783 if (!phase->C->method()->is_strict()) 784 // Can't trust native compilers to properly fold strict double 785 // division with round-to-zero on this platform. 786 #endif 787 { 788 // If divisor is a constant and not zero, divide them numbers 789 if( t1->base() == Type::DoubleCon && 790 t2->base() == Type::DoubleCon && 791 t2->getd() != 0.0 ) // could be negative zero 792 return TypeD::make( t1->getd()/t2->getd() ); 793 } 794 795 // If the dividend is a constant zero 796 // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) 797 // Test TypeF::ZERO is not sufficient as it could be negative zero 798 if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 ) 799 return TypeD::ZERO; 800 801 // Otherwise we give up all hope 802 return Type::DOUBLE; 803 } 804 805 806 //------------------------------isA_Copy--------------------------------------- 807 // Dividing by self is 1. 808 // If the divisor is 1, we are an identity on the dividend. 809 Node* DivDNode::Identity(PhaseGVN* phase) { 810 return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this; 811 } 812 813 //------------------------------Idealize--------------------------------------- 814 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) { 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 const Type *t2 = phase->type( in(2) ); 820 if( t2 == TypeD::ONE ) // Identity? 821 return NULL; // Skip it 822 823 const TypeD *td = t2->isa_double_constant(); 824 if( !td ) return NULL; 825 if( td->base() != Type::DoubleCon ) return NULL; 826 827 // Check for out of range values 828 if( td->is_nan() || !td->is_finite() ) return NULL; 829 830 // Get the value 831 double d = td->getd(); 832 int exp; 833 834 // Only for special case of dividing by a power of 2 835 if( frexp(d, &exp) != 0.5 ) return NULL; 836 837 // Limit the range of acceptable exponents 838 if( exp < -1021 || exp > 1022 ) return NULL; 839 840 // Compute the reciprocal 841 double reciprocal = 1.0 / d; 842 843 assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); 844 845 // return multiplication by the reciprocal 846 return (new MulDNode(in(1), phase->makecon(TypeD::make(reciprocal)))); 847 } 848 849 //============================================================================= 850 //------------------------------Idealize--------------------------------------- 851 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) { 852 // Check for dead control input 853 if( in(0) && remove_dead_region(phase, can_reshape) ) return this; 854 // Don't bother trying to transform a dead node 855 if( in(0) && in(0)->is_top() ) return NULL; 856 857 // Get the modulus 858 const Type *t = phase->type( in(2) ); 859 if( t == Type::TOP ) return NULL; 860 const TypeInt *ti = t->is_int(); 861 862 // Check for useless control input 863 // Check for excluding mod-zero case 864 if (in(0) && (ti->_hi < 0 || ti->_lo > 0)) { 865 set_req(0, NULL); // Yank control input 866 return this; 867 } 868 869 // See if we are MOD'ing by 2^k or 2^k-1. 870 if( !ti->is_con() ) return NULL; 871 jint con = ti->get_con(); 872 873 Node *hook = new Node(1); 874 875 // First, special check for modulo 2^k-1 876 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) { 877 uint k = exact_log2(con+1); // Extract k 878 879 // Basic algorithm by David Detlefs. See fastmod_int.java for gory details. 880 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*/}; 881 int trip_count = 1; 882 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; 883 884 // If the unroll factor is not too large, and if conditional moves are 885 // ok, then use this case 886 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) { 887 Node *x = in(1); // Value being mod'd 888 Node *divisor = in(2); // Also is mask 889 890 hook->init_req(0, x); // Add a use to x to prevent him from dying 891 // Generate code to reduce X rapidly to nearly 2^k-1. 892 for( int i = 0; i < trip_count; i++ ) { 893 Node *xl = phase->transform( new AndINode(x,divisor) ); 894 Node *xh = phase->transform( new RShiftINode(x,phase->intcon(k)) ); // Must be signed 895 x = phase->transform( new AddINode(xh,xl) ); 896 hook->set_req(0, x); 897 } 898 899 // Generate sign-fixup code. Was original value positive? 900 // int hack_res = (i >= 0) ? divisor : 1; 901 Node *cmp1 = phase->transform( new CmpINode( in(1), phase->intcon(0) ) ); 902 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) ); 903 Node *cmov1= phase->transform( new CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) ); 904 // if( x >= hack_res ) x -= divisor; 905 Node *sub = phase->transform( new SubINode( x, divisor ) ); 906 Node *cmp2 = phase->transform( new CmpINode( x, cmov1 ) ); 907 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) ); 908 // Convention is to not transform the return value of an Ideal 909 // since Ideal is expected to return a modified 'this' or a new node. 910 Node *cmov2= new CMoveINode(bol2, x, sub, TypeInt::INT); 911 // cmov2 is now the mod 912 913 // Now remove the bogus extra edges used to keep things alive 914 if (can_reshape) { 915 phase->is_IterGVN()->remove_dead_node(hook); 916 } else { 917 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 918 } 919 return cmov2; 920 } 921 } 922 923 // Fell thru, the unroll case is not appropriate. Transform the modulo 924 // into a long multiply/int multiply/subtract case 925 926 // Cannot handle mod 0, and min_jint isn't handled by the transform 927 if( con == 0 || con == min_jint ) return NULL; 928 929 // Get the absolute value of the constant; at this point, we can use this 930 jint pos_con = (con >= 0) ? con : -con; 931 932 // integer Mod 1 is always 0 933 if( pos_con == 1 ) return new ConINode(TypeInt::ZERO); 934 935 int log2_con = -1; 936 937 // If this is a power of two, they maybe we can mask it 938 if( is_power_of_2(pos_con) ) { 939 log2_con = log2_intptr((intptr_t)pos_con); 940 941 const Type *dt = phase->type(in(1)); 942 const TypeInt *dti = dt->isa_int(); 943 944 // See if this can be masked, if the dividend is non-negative 945 if( dti && dti->_lo >= 0 ) 946 return ( new AndINode( in(1), phase->intcon( pos_con-1 ) ) ); 947 } 948 949 // Save in(1) so that it cannot be changed or deleted 950 hook->init_req(0, in(1)); 951 952 // Divide using the transform from DivI to MulL 953 Node *result = transform_int_divide( phase, in(1), pos_con ); 954 if (result != NULL) { 955 Node *divide = phase->transform(result); 956 957 // Re-multiply, using a shift if this is a power of two 958 Node *mult = NULL; 959 960 if( log2_con >= 0 ) 961 mult = phase->transform( new LShiftINode( divide, phase->intcon( log2_con ) ) ); 962 else 963 mult = phase->transform( new MulINode( divide, phase->intcon( pos_con ) ) ); 964 965 // Finally, subtract the multiplied divided value from the original 966 result = new SubINode( in(1), mult ); 967 } 968 969 // Now remove the bogus extra edges used to keep things alive 970 if (can_reshape) { 971 phase->is_IterGVN()->remove_dead_node(hook); 972 } else { 973 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 974 } 975 976 // return the value 977 return result; 978 } 979 980 //------------------------------Value------------------------------------------ 981 const Type* ModINode::Value(PhaseGVN* phase) const { 982 // Either input is TOP ==> the result is TOP 983 const Type *t1 = phase->type( in(1) ); 984 const Type *t2 = phase->type( in(2) ); 985 if( t1 == Type::TOP ) return Type::TOP; 986 if( t2 == Type::TOP ) return Type::TOP; 987 988 // We always generate the dynamic check for 0. 989 // 0 MOD X is 0 990 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; 991 // X MOD X is 0 992 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO; 993 994 // Either input is BOTTOM ==> the result is the local BOTTOM 995 const Type *bot = bottom_type(); 996 if( (t1 == bot) || (t2 == bot) || 997 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 998 return bot; 999 1000 const TypeInt *i1 = t1->is_int(); 1001 const TypeInt *i2 = t2->is_int(); 1002 if( !i1->is_con() || !i2->is_con() ) { 1003 if( i1->_lo >= 0 && i2->_lo >= 0 ) 1004 return TypeInt::POS; 1005 // If both numbers are not constants, we know little. 1006 return TypeInt::INT; 1007 } 1008 // Mod by zero? Throw exception at runtime! 1009 if( !i2->get_con() ) return TypeInt::POS; 1010 1011 // We must be modulo'ing 2 float constants. 1012 // Check for min_jint % '-1', result is defined to be '0'. 1013 if( i1->get_con() == min_jint && i2->get_con() == -1 ) 1014 return TypeInt::ZERO; 1015 1016 return TypeInt::make( i1->get_con() % i2->get_con() ); 1017 } 1018 1019 1020 //============================================================================= 1021 //------------------------------Idealize--------------------------------------- 1022 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1023 // Check for dead control input 1024 if( in(0) && remove_dead_region(phase, can_reshape) ) return this; 1025 // Don't bother trying to transform a dead node 1026 if( in(0) && in(0)->is_top() ) return NULL; 1027 1028 // Get the modulus 1029 const Type *t = phase->type( in(2) ); 1030 if( t == Type::TOP ) return NULL; 1031 const TypeLong *tl = t->is_long(); 1032 1033 // Check for useless control input 1034 // Check for excluding mod-zero case 1035 if (in(0) && (tl->_hi < 0 || tl->_lo > 0)) { 1036 set_req(0, NULL); // Yank control input 1037 return this; 1038 } 1039 1040 // See if we are MOD'ing by 2^k or 2^k-1. 1041 if( !tl->is_con() ) return NULL; 1042 jlong con = tl->get_con(); 1043 1044 Node *hook = new Node(1); 1045 1046 // Expand mod 1047 if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) { 1048 uint k = exact_log2_long(con+1); // Extract k 1049 1050 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details. 1051 // Used to help a popular random number generator which does a long-mod 1052 // of 2^31-1 and shows up in SpecJBB and SciMark. 1053 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*/}; 1054 int trip_count = 1; 1055 if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; 1056 1057 // If the unroll factor is not too large, and if conditional moves are 1058 // ok, then use this case 1059 if( trip_count <= 5 && ConditionalMoveLimit != 0 ) { 1060 Node *x = in(1); // Value being mod'd 1061 Node *divisor = in(2); // Also is mask 1062 1063 hook->init_req(0, x); // Add a use to x to prevent him from dying 1064 // Generate code to reduce X rapidly to nearly 2^k-1. 1065 for( int i = 0; i < trip_count; i++ ) { 1066 Node *xl = phase->transform( new AndLNode(x,divisor) ); 1067 Node *xh = phase->transform( new RShiftLNode(x,phase->intcon(k)) ); // Must be signed 1068 x = phase->transform( new AddLNode(xh,xl) ); 1069 hook->set_req(0, x); // Add a use to x to prevent him from dying 1070 } 1071 1072 // Generate sign-fixup code. Was original value positive? 1073 // long hack_res = (i >= 0) ? divisor : CONST64(1); 1074 Node *cmp1 = phase->transform( new CmpLNode( in(1), phase->longcon(0) ) ); 1075 Node *bol1 = phase->transform( new BoolNode( cmp1, BoolTest::ge ) ); 1076 Node *cmov1= phase->transform( new CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) ); 1077 // if( x >= hack_res ) x -= divisor; 1078 Node *sub = phase->transform( new SubLNode( x, divisor ) ); 1079 Node *cmp2 = phase->transform( new CmpLNode( x, cmov1 ) ); 1080 Node *bol2 = phase->transform( new BoolNode( cmp2, BoolTest::ge ) ); 1081 // Convention is to not transform the return value of an Ideal 1082 // since Ideal is expected to return a modified 'this' or a new node. 1083 Node *cmov2= new CMoveLNode(bol2, x, sub, TypeLong::LONG); 1084 // cmov2 is now the mod 1085 1086 // Now remove the bogus extra edges used to keep things alive 1087 if (can_reshape) { 1088 phase->is_IterGVN()->remove_dead_node(hook); 1089 } else { 1090 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 1091 } 1092 return cmov2; 1093 } 1094 } 1095 1096 // Fell thru, the unroll case is not appropriate. Transform the modulo 1097 // into a long multiply/int multiply/subtract case 1098 1099 // Cannot handle mod 0, and min_jlong isn't handled by the transform 1100 if( con == 0 || con == min_jlong ) return NULL; 1101 1102 // Get the absolute value of the constant; at this point, we can use this 1103 jlong pos_con = (con >= 0) ? con : -con; 1104 1105 // integer Mod 1 is always 0 1106 if( pos_con == 1 ) return new ConLNode(TypeLong::ZERO); 1107 1108 int log2_con = -1; 1109 1110 // If this is a power of two, then maybe we can mask it 1111 if( is_power_of_2_long(pos_con) ) { 1112 log2_con = exact_log2_long(pos_con); 1113 1114 const Type *dt = phase->type(in(1)); 1115 const TypeLong *dtl = dt->isa_long(); 1116 1117 // See if this can be masked, if the dividend is non-negative 1118 if( dtl && dtl->_lo >= 0 ) 1119 return ( new AndLNode( in(1), phase->longcon( pos_con-1 ) ) ); 1120 } 1121 1122 // Save in(1) so that it cannot be changed or deleted 1123 hook->init_req(0, in(1)); 1124 1125 // Divide using the transform from DivL to MulL 1126 Node *result = transform_long_divide( phase, in(1), pos_con ); 1127 if (result != NULL) { 1128 Node *divide = phase->transform(result); 1129 1130 // Re-multiply, using a shift if this is a power of two 1131 Node *mult = NULL; 1132 1133 if( log2_con >= 0 ) 1134 mult = phase->transform( new LShiftLNode( divide, phase->intcon( log2_con ) ) ); 1135 else 1136 mult = phase->transform( new MulLNode( divide, phase->longcon( pos_con ) ) ); 1137 1138 // Finally, subtract the multiplied divided value from the original 1139 result = new SubLNode( in(1), mult ); 1140 } 1141 1142 // Now remove the bogus extra edges used to keep things alive 1143 if (can_reshape) { 1144 phase->is_IterGVN()->remove_dead_node(hook); 1145 } else { 1146 hook->set_req(0, NULL); // Just yank bogus edge during Parse phase 1147 } 1148 1149 // return the value 1150 return result; 1151 } 1152 1153 //------------------------------Value------------------------------------------ 1154 const Type* ModLNode::Value(PhaseGVN* phase) const { 1155 // Either input is TOP ==> the result is TOP 1156 const Type *t1 = phase->type( in(1) ); 1157 const Type *t2 = phase->type( in(2) ); 1158 if( t1 == Type::TOP ) return Type::TOP; 1159 if( t2 == Type::TOP ) return Type::TOP; 1160 1161 // We always generate the dynamic check for 0. 1162 // 0 MOD X is 0 1163 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; 1164 // X MOD X is 0 1165 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO; 1166 1167 // Either input is BOTTOM ==> the result is the local BOTTOM 1168 const Type *bot = bottom_type(); 1169 if( (t1 == bot) || (t2 == bot) || 1170 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1171 return bot; 1172 1173 const TypeLong *i1 = t1->is_long(); 1174 const TypeLong *i2 = t2->is_long(); 1175 if( !i1->is_con() || !i2->is_con() ) { 1176 if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) ) 1177 return TypeLong::POS; 1178 // If both numbers are not constants, we know little. 1179 return TypeLong::LONG; 1180 } 1181 // Mod by zero? Throw exception at runtime! 1182 if( !i2->get_con() ) return TypeLong::POS; 1183 1184 // We must be modulo'ing 2 float constants. 1185 // Check for min_jint % '-1', result is defined to be '0'. 1186 if( i1->get_con() == min_jlong && i2->get_con() == -1 ) 1187 return TypeLong::ZERO; 1188 1189 return TypeLong::make( i1->get_con() % i2->get_con() ); 1190 } 1191 1192 1193 //============================================================================= 1194 //------------------------------Value------------------------------------------ 1195 const Type* ModFNode::Value(PhaseGVN* phase) const { 1196 // Either input is TOP ==> the result is TOP 1197 const Type *t1 = phase->type( in(1) ); 1198 const Type *t2 = phase->type( in(2) ); 1199 if( t1 == Type::TOP ) return Type::TOP; 1200 if( t2 == Type::TOP ) return Type::TOP; 1201 1202 // Either input is BOTTOM ==> the result is the local BOTTOM 1203 const Type *bot = bottom_type(); 1204 if( (t1 == bot) || (t2 == bot) || 1205 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1206 return bot; 1207 1208 // If either number is not a constant, we know nothing. 1209 if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) { 1210 return Type::FLOAT; // note: x%x can be either NaN or 0 1211 } 1212 1213 float f1 = t1->getf(); 1214 float f2 = t2->getf(); 1215 jint x1 = jint_cast(f1); // note: *(int*)&f1, not just (int)f1 1216 jint x2 = jint_cast(f2); 1217 1218 // If either is a NaN, return an input NaN 1219 if (g_isnan(f1)) return t1; 1220 if (g_isnan(f2)) return t2; 1221 1222 // If an operand is infinity or the divisor is +/- zero, punt. 1223 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint) 1224 return Type::FLOAT; 1225 1226 // We must be modulo'ing 2 float constants. 1227 // Make sure that the sign of the fmod is equal to the sign of the dividend 1228 jint xr = jint_cast(fmod(f1, f2)); 1229 if ((x1 ^ xr) < 0) { 1230 xr ^= min_jint; 1231 } 1232 1233 return TypeF::make(jfloat_cast(xr)); 1234 } 1235 1236 1237 //============================================================================= 1238 //------------------------------Value------------------------------------------ 1239 const Type* ModDNode::Value(PhaseGVN* phase) const { 1240 // Either input is TOP ==> the result is TOP 1241 const Type *t1 = phase->type( in(1) ); 1242 const Type *t2 = phase->type( in(2) ); 1243 if( t1 == Type::TOP ) return Type::TOP; 1244 if( t2 == Type::TOP ) return Type::TOP; 1245 1246 // Either input is BOTTOM ==> the result is the local BOTTOM 1247 const Type *bot = bottom_type(); 1248 if( (t1 == bot) || (t2 == bot) || 1249 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 1250 return bot; 1251 1252 // If either number is not a constant, we know nothing. 1253 if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) { 1254 return Type::DOUBLE; // note: x%x can be either NaN or 0 1255 } 1256 1257 double f1 = t1->getd(); 1258 double f2 = t2->getd(); 1259 jlong x1 = jlong_cast(f1); // note: *(long*)&f1, not just (long)f1 1260 jlong x2 = jlong_cast(f2); 1261 1262 // If either is a NaN, return an input NaN 1263 if (g_isnan(f1)) return t1; 1264 if (g_isnan(f2)) return t2; 1265 1266 // If an operand is infinity or the divisor is +/- zero, punt. 1267 if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong) 1268 return Type::DOUBLE; 1269 1270 // We must be modulo'ing 2 double constants. 1271 // Make sure that the sign of the fmod is equal to the sign of the dividend 1272 jlong xr = jlong_cast(fmod(f1, f2)); 1273 if ((x1 ^ xr) < 0) { 1274 xr ^= min_jlong; 1275 } 1276 1277 return TypeD::make(jdouble_cast(xr)); 1278 } 1279 1280 //============================================================================= 1281 1282 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) { 1283 init_req(0, c); 1284 init_req(1, dividend); 1285 init_req(2, divisor); 1286 } 1287 1288 //------------------------------make------------------------------------------ 1289 DivModINode* DivModINode::make(Node* div_or_mod) { 1290 Node* n = div_or_mod; 1291 assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI, 1292 "only div or mod input pattern accepted"); 1293 1294 DivModINode* divmod = new DivModINode(n->in(0), n->in(1), n->in(2)); 1295 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num); 1296 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num); 1297 return divmod; 1298 } 1299 1300 //------------------------------make------------------------------------------ 1301 DivModLNode* DivModLNode::make(Node* div_or_mod) { 1302 Node* n = div_or_mod; 1303 assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL, 1304 "only div or mod input pattern accepted"); 1305 1306 DivModLNode* divmod = new DivModLNode(n->in(0), n->in(1), n->in(2)); 1307 Node* dproj = new ProjNode(divmod, DivModNode::div_proj_num); 1308 Node* mproj = new ProjNode(divmod, DivModNode::mod_proj_num); 1309 return divmod; 1310 } 1311 1312 //------------------------------match------------------------------------------ 1313 // return result(s) along with their RegMask info 1314 Node *DivModINode::match(const ProjNode *proj, const Matcher *match, const RegMask* mask) { 1315 uint ideal_reg = proj->ideal_reg(); 1316 RegMask rm; 1317 if (proj->_con == div_proj_num) { 1318 rm = match->divI_proj_mask(); 1319 } else { 1320 assert(proj->_con == mod_proj_num, "must be div or mod projection"); 1321 rm = match->modI_proj_mask(); 1322 } 1323 return new MachProjNode(this, proj->_con, rm, ideal_reg); 1324 } 1325 1326 1327 //------------------------------match------------------------------------------ 1328 // return result(s) along with their RegMask info 1329 Node *DivModLNode::match(const ProjNode *proj, const Matcher *match, const RegMask* mask) { 1330 uint ideal_reg = proj->ideal_reg(); 1331 RegMask rm; 1332 if (proj->_con == div_proj_num) { 1333 rm = match->divL_proj_mask(); 1334 } else { 1335 assert(proj->_con == mod_proj_num, "must be div or mod projection"); 1336 rm = match->modL_proj_mask(); 1337 } 1338 return new MachProjNode(this, proj->_con, rm, ideal_reg); 1339 }