src/share/vm/opto/divnode.cpp

Wed, 27 Aug 2008 09:15:46 -0700

author
kvn
date
Wed, 27 Aug 2008 09:15:46 -0700
changeset 740
ab075d07f1ba
parent 729
616a07a75c3c
child 835
cc80376deb0c
permissions
-rw-r--r--

6736417: Fastdebug C2 crashes in StoreBNode::Ideal
Summary: The result of step_through_mergemem() and remove_dead_region() is not checked in some cases.
Reviewed-by: never

     1 /*
     2  * Copyright 1997-2008 Sun Microsystems, Inc.  All Rights Reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 // Portions of code courtesy of Clifford Click
    27 // Optimization - Graph Style
    29 #include "incls/_precompiled.incl"
    30 #include "incls/_divnode.cpp.incl"
    31 #include <math.h>
    33 //----------------------magic_int_divide_constants-----------------------------
    34 // Compute magic multiplier and shift constant for converting a 32 bit divide
    35 // by constant into a multiply/shift/add series. Return false if calculations
    36 // fail.
    37 //
    38 // Borrowed almost verbatum from Hacker's Delight by Henry S. Warren, Jr. with
    39 // minor type name and parameter changes.
    40 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
    41   int32_t p;
    42   uint32_t ad, anc, delta, q1, r1, q2, r2, t;
    43   const uint32_t two31 = 0x80000000L;     // 2**31.
    45   ad = ABS(d);
    46   if (d == 0 || d == 1) return false;
    47   t = two31 + ((uint32_t)d >> 31);
    48   anc = t - 1 - t%ad;     // Absolute value of nc.
    49   p = 31;                 // Init. p.
    50   q1 = two31/anc;         // Init. q1 = 2**p/|nc|.
    51   r1 = two31 - q1*anc;    // Init. r1 = rem(2**p, |nc|).
    52   q2 = two31/ad;          // Init. q2 = 2**p/|d|.
    53   r2 = two31 - q2*ad;     // Init. r2 = rem(2**p, |d|).
    54   do {
    55     p = p + 1;
    56     q1 = 2*q1;            // Update q1 = 2**p/|nc|.
    57     r1 = 2*r1;            // Update r1 = rem(2**p, |nc|).
    58     if (r1 >= anc) {      // (Must be an unsigned
    59       q1 = q1 + 1;        // comparison here).
    60       r1 = r1 - anc;
    61     }
    62     q2 = 2*q2;            // Update q2 = 2**p/|d|.
    63     r2 = 2*r2;            // Update r2 = rem(2**p, |d|).
    64     if (r2 >= ad) {       // (Must be an unsigned
    65       q2 = q2 + 1;        // comparison here).
    66       r2 = r2 - ad;
    67     }
    68     delta = ad - r2;
    69   } while (q1 < delta || (q1 == delta && r1 == 0));
    71   M = q2 + 1;
    72   if (d < 0) M = -M;      // Magic number and
    73   s = p - 32;             // shift amount to return.
    75   return true;
    76 }
    78 //--------------------------transform_int_divide-------------------------------
    79 // Convert a division by constant divisor into an alternate Ideal graph.
    80 // Return NULL if no transformation occurs.
    81 static Node *transform_int_divide( PhaseGVN *phase, Node *dividend, jint divisor ) {
    83   // Check for invalid divisors
    84   assert( divisor != 0 && divisor != min_jint,
    85           "bad divisor for transforming to long multiply" );
    87   bool d_pos = divisor >= 0;
    88   jint d = d_pos ? divisor : -divisor;
    89   const int N = 32;
    91   // Result
    92   Node *q = NULL;
    94   if (d == 1) {
    95     // division by +/- 1
    96     if (!d_pos) {
    97       // Just negate the value
    98       q = new (phase->C, 3) SubINode(phase->intcon(0), dividend);
    99     }
   100   } else if ( is_power_of_2(d) ) {
   101     // division by +/- a power of 2
   103     // See if we can simply do a shift without rounding
   104     bool needs_rounding = true;
   105     const Type *dt = phase->type(dividend);
   106     const TypeInt *dti = dt->isa_int();
   107     if (dti && dti->_lo >= 0) {
   108       // we don't need to round a positive dividend
   109       needs_rounding = false;
   110     } else if( dividend->Opcode() == Op_AndI ) {
   111       // An AND mask of sufficient size clears the low bits and
   112       // I can avoid rounding.
   113       const TypeInt *andconi = phase->type( dividend->in(2) )->isa_int();
   114       if( andconi && andconi->is_con(-d) ) {
   115         dividend = dividend->in(1);
   116         needs_rounding = false;
   117       }
   118     }
   120     // Add rounding to the shift to handle the sign bit
   121     int l = log2_intptr(d-1)+1;
   122     if (needs_rounding) {
   123       // Divide-by-power-of-2 can be made into a shift, but you have to do
   124       // more math for the rounding.  You need to add 0 for positive
   125       // numbers, and "i-1" for negative numbers.  Example: i=4, so the
   126       // shift is by 2.  You need to add 3 to negative dividends and 0 to
   127       // positive ones.  So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
   128       // (-2+3)>>2 becomes 0, etc.
   130       // Compute 0 or -1, based on sign bit
   131       Node *sign = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N - 1)));
   132       // Mask sign bit to the low sign bits
   133       Node *round = phase->transform(new (phase->C, 3) URShiftINode(sign, phase->intcon(N - l)));
   134       // Round up before shifting
   135       dividend = phase->transform(new (phase->C, 3) AddINode(dividend, round));
   136     }
   138     // Shift for division
   139     q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l));
   141     if (!d_pos) {
   142       q = new (phase->C, 3) SubINode(phase->intcon(0), phase->transform(q));
   143     }
   144   } else {
   145     // Attempt the jint constant divide -> multiply transform found in
   146     //   "Division by Invariant Integers using Multiplication"
   147     //     by Granlund and Montgomery
   148     // See also "Hacker's Delight", chapter 10 by Warren.
   150     jint magic_const;
   151     jint shift_const;
   152     if (magic_int_divide_constants(d, magic_const, shift_const)) {
   153       Node *magic = phase->longcon(magic_const);
   154       Node *dividend_long = phase->transform(new (phase->C, 2) ConvI2LNode(dividend));
   156       // Compute the high half of the dividend x magic multiplication
   157       Node *mul_hi = phase->transform(new (phase->C, 3) MulLNode(dividend_long, magic));
   159       if (magic_const < 0) {
   160         mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N)));
   161         mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
   163         // The magic multiplier is too large for a 32 bit constant. We've adjusted
   164         // it down by 2^32, but have to add 1 dividend back in after the multiplication.
   165         // This handles the "overflow" case described by Granlund and Montgomery.
   166         mul_hi = phase->transform(new (phase->C, 3) AddINode(dividend, mul_hi));
   168         // Shift over the (adjusted) mulhi
   169         if (shift_const != 0) {
   170           mul_hi = phase->transform(new (phase->C, 3) RShiftINode(mul_hi, phase->intcon(shift_const)));
   171         }
   172       } else {
   173         // No add is required, we can merge the shifts together.
   174         mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(N + shift_const)));
   175         mul_hi = phase->transform(new (phase->C, 2) ConvL2INode(mul_hi));
   176       }
   178       // Get a 0 or -1 from the sign of the dividend.
   179       Node *addend0 = mul_hi;
   180       Node *addend1 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1)));
   182       // If the divisor is negative, swap the order of the input addends;
   183       // this has the effect of negating the quotient.
   184       if (!d_pos) {
   185         Node *temp = addend0; addend0 = addend1; addend1 = temp;
   186       }
   188       // Adjust the final quotient by subtracting -1 (adding 1)
   189       // from the mul_hi.
   190       q = new (phase->C, 3) SubINode(addend0, addend1);
   191     }
   192   }
   194   return q;
   195 }
   197 //---------------------magic_long_divide_constants-----------------------------
   198 // Compute magic multiplier and shift constant for converting a 64 bit divide
   199 // by constant into a multiply/shift/add series. Return false if calculations
   200 // fail.
   201 //
   202 // Borrowed almost verbatum from Hacker's Delight by Henry S. Warren, Jr. with
   203 // minor type name and parameter changes.  Adjusted to 64 bit word width.
   204 static bool magic_long_divide_constants(jlong d, jlong &M, jint &s) {
   205   int64_t p;
   206   uint64_t ad, anc, delta, q1, r1, q2, r2, t;
   207   const uint64_t two63 = 0x8000000000000000LL;     // 2**63.
   209   ad = ABS(d);
   210   if (d == 0 || d == 1) return false;
   211   t = two63 + ((uint64_t)d >> 63);
   212   anc = t - 1 - t%ad;     // Absolute value of nc.
   213   p = 63;                 // Init. p.
   214   q1 = two63/anc;         // Init. q1 = 2**p/|nc|.
   215   r1 = two63 - q1*anc;    // Init. r1 = rem(2**p, |nc|).
   216   q2 = two63/ad;          // Init. q2 = 2**p/|d|.
   217   r2 = two63 - q2*ad;     // Init. r2 = rem(2**p, |d|).
   218   do {
   219     p = p + 1;
   220     q1 = 2*q1;            // Update q1 = 2**p/|nc|.
   221     r1 = 2*r1;            // Update r1 = rem(2**p, |nc|).
   222     if (r1 >= anc) {      // (Must be an unsigned
   223       q1 = q1 + 1;        // comparison here).
   224       r1 = r1 - anc;
   225     }
   226     q2 = 2*q2;            // Update q2 = 2**p/|d|.
   227     r2 = 2*r2;            // Update r2 = rem(2**p, |d|).
   228     if (r2 >= ad) {       // (Must be an unsigned
   229       q2 = q2 + 1;        // comparison here).
   230       r2 = r2 - ad;
   231     }
   232     delta = ad - r2;
   233   } while (q1 < delta || (q1 == delta && r1 == 0));
   235   M = q2 + 1;
   236   if (d < 0) M = -M;      // Magic number and
   237   s = p - 64;             // shift amount to return.
   239   return true;
   240 }
   242 //---------------------long_by_long_mulhi--------------------------------------
   243 // Generate ideal node graph for upper half of a 64 bit x 64 bit multiplication
   244 static Node *long_by_long_mulhi( PhaseGVN *phase, Node *dividend, jlong magic_const) {
   245   // If the architecture supports a 64x64 mulhi, there is
   246   // no need to synthesize it in ideal nodes.
   247   if (Matcher::has_match_rule(Op_MulHiL)) {
   248     Node *v = phase->longcon(magic_const);
   249     return new (phase->C, 3) MulHiLNode(dividend, v);
   250   }
   252   const int N = 64;
   254   Node *u_hi = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N / 2)));
   255   Node *u_lo = phase->transform(new (phase->C, 3) AndLNode(dividend, phase->longcon(0xFFFFFFFF)));
   257   Node *v_hi = phase->longcon(magic_const >> N/2);
   258   Node *v_lo = phase->longcon(magic_const & 0XFFFFFFFF);
   260   Node *hihi_product = phase->transform(new (phase->C, 3) MulLNode(u_hi, v_hi));
   261   Node *hilo_product = phase->transform(new (phase->C, 3) MulLNode(u_hi, v_lo));
   262   Node *lohi_product = phase->transform(new (phase->C, 3) MulLNode(u_lo, v_hi));
   263   Node *lolo_product = phase->transform(new (phase->C, 3) MulLNode(u_lo, v_lo));
   265   Node *t1 = phase->transform(new (phase->C, 3) URShiftLNode(lolo_product, phase->intcon(N / 2)));
   266   Node *t2 = phase->transform(new (phase->C, 3) AddLNode(hilo_product, t1));
   268   // Construct both t3 and t4 before transforming so t2 doesn't go dead
   269   // prematurely.
   270   Node *t3 = new (phase->C, 3) RShiftLNode(t2, phase->intcon(N / 2));
   271   Node *t4 = new (phase->C, 3) AndLNode(t2, phase->longcon(0xFFFFFFFF));
   272   t3 = phase->transform(t3);
   273   t4 = phase->transform(t4);
   275   Node *t5 = phase->transform(new (phase->C, 3) AddLNode(t4, lohi_product));
   276   Node *t6 = phase->transform(new (phase->C, 3) RShiftLNode(t5, phase->intcon(N / 2)));
   277   Node *t7 = phase->transform(new (phase->C, 3) AddLNode(t3, hihi_product));
   279   return new (phase->C, 3) AddLNode(t7, t6);
   280 }
   283 //--------------------------transform_long_divide------------------------------
   284 // Convert a division by constant divisor into an alternate Ideal graph.
   285 // Return NULL if no transformation occurs.
   286 static Node *transform_long_divide( PhaseGVN *phase, Node *dividend, jlong divisor ) {
   287   // Check for invalid divisors
   288   assert( divisor != 0L && divisor != min_jlong,
   289           "bad divisor for transforming to long multiply" );
   291   bool d_pos = divisor >= 0;
   292   jlong d = d_pos ? divisor : -divisor;
   293   const int N = 64;
   295   // Result
   296   Node *q = NULL;
   298   if (d == 1) {
   299     // division by +/- 1
   300     if (!d_pos) {
   301       // Just negate the value
   302       q = new (phase->C, 3) SubLNode(phase->longcon(0), dividend);
   303     }
   304   } else if ( is_power_of_2_long(d) ) {
   306     // division by +/- a power of 2
   308     // See if we can simply do a shift without rounding
   309     bool needs_rounding = true;
   310     const Type *dt = phase->type(dividend);
   311     const TypeLong *dtl = dt->isa_long();
   313     if (dtl && dtl->_lo > 0) {
   314       // we don't need to round a positive dividend
   315       needs_rounding = false;
   316     } else if( dividend->Opcode() == Op_AndL ) {
   317       // An AND mask of sufficient size clears the low bits and
   318       // I can avoid rounding.
   319       const TypeLong *andconl = phase->type( dividend->in(2) )->isa_long();
   320       if( andconl && andconl->is_con(-d)) {
   321         dividend = dividend->in(1);
   322         needs_rounding = false;
   323       }
   324     }
   326     // Add rounding to the shift to handle the sign bit
   327     int l = log2_long(d-1)+1;
   328     if (needs_rounding) {
   329       // Divide-by-power-of-2 can be made into a shift, but you have to do
   330       // more math for the rounding.  You need to add 0 for positive
   331       // numbers, and "i-1" for negative numbers.  Example: i=4, so the
   332       // shift is by 2.  You need to add 3 to negative dividends and 0 to
   333       // positive ones.  So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1,
   334       // (-2+3)>>2 becomes 0, etc.
   336       // Compute 0 or -1, based on sign bit
   337       Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N - 1)));
   338       // Mask sign bit to the low sign bits
   339       Node *round = phase->transform(new (phase->C, 3) URShiftLNode(sign, phase->intcon(N - l)));
   340       // Round up before shifting
   341       dividend = phase->transform(new (phase->C, 3) AddLNode(dividend, round));
   342     }
   344     // Shift for division
   345     q = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(l));
   347     if (!d_pos) {
   348       q = new (phase->C, 3) SubLNode(phase->longcon(0), phase->transform(q));
   349     }
   350   } else {
   351     // Attempt the jlong constant divide -> multiply transform found in
   352     //   "Division by Invariant Integers using Multiplication"
   353     //     by Granlund and Montgomery
   354     // See also "Hacker's Delight", chapter 10 by Warren.
   356     jlong magic_const;
   357     jint shift_const;
   358     if (magic_long_divide_constants(d, magic_const, shift_const)) {
   359       // Compute the high half of the dividend x magic multiplication
   360       Node *mul_hi = phase->transform(long_by_long_mulhi(phase, dividend, magic_const));
   362       // The high half of the 128-bit multiply is computed.
   363       if (magic_const < 0) {
   364         // The magic multiplier is too large for a 64 bit constant. We've adjusted
   365         // it down by 2^64, but have to add 1 dividend back in after the multiplication.
   366         // This handles the "overflow" case described by Granlund and Montgomery.
   367         mul_hi = phase->transform(new (phase->C, 3) AddLNode(dividend, mul_hi));
   368       }
   370       // Shift over the (adjusted) mulhi
   371       if (shift_const != 0) {
   372         mul_hi = phase->transform(new (phase->C, 3) RShiftLNode(mul_hi, phase->intcon(shift_const)));
   373       }
   375       // Get a 0 or -1 from the sign of the dividend.
   376       Node *addend0 = mul_hi;
   377       Node *addend1 = phase->transform(new (phase->C, 3) RShiftLNode(dividend, phase->intcon(N-1)));
   379       // If the divisor is negative, swap the order of the input addends;
   380       // this has the effect of negating the quotient.
   381       if (!d_pos) {
   382         Node *temp = addend0; addend0 = addend1; addend1 = temp;
   383       }
   385       // Adjust the final quotient by subtracting -1 (adding 1)
   386       // from the mul_hi.
   387       q = new (phase->C, 3) SubLNode(addend0, addend1);
   388     }
   389   }
   391   return q;
   392 }
   394 //=============================================================================
   395 //------------------------------Identity---------------------------------------
   396 // If the divisor is 1, we are an identity on the dividend.
   397 Node *DivINode::Identity( PhaseTransform *phase ) {
   398   return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this;
   399 }
   401 //------------------------------Idealize---------------------------------------
   402 // Divides can be changed to multiplies and/or shifts
   403 Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) {
   404   if (in(0) && remove_dead_region(phase, can_reshape))  return this;
   405   // Don't bother trying to transform a dead node
   406   if( in(0) && in(0)->is_top() )  return NULL;
   408   const Type *t = phase->type( in(2) );
   409   if( t == TypeInt::ONE )       // Identity?
   410     return NULL;                // Skip it
   412   const TypeInt *ti = t->isa_int();
   413   if( !ti ) return NULL;
   414   if( !ti->is_con() ) return NULL;
   415   jint i = ti->get_con();       // Get divisor
   417   if (i == 0) return NULL;      // Dividing by zero constant does not idealize
   419   set_req(0,NULL);              // Dividing by a not-zero constant; no faulting
   421   // Dividing by MININT does not optimize as a power-of-2 shift.
   422   if( i == min_jint ) return NULL;
   424   return transform_int_divide( phase, in(1), i );
   425 }
   427 //------------------------------Value------------------------------------------
   428 // A DivINode divides its inputs.  The third input is a Control input, used to
   429 // prevent hoisting the divide above an unsafe test.
   430 const Type *DivINode::Value( PhaseTransform *phase ) const {
   431   // Either input is TOP ==> the result is TOP
   432   const Type *t1 = phase->type( in(1) );
   433   const Type *t2 = phase->type( in(2) );
   434   if( t1 == Type::TOP ) return Type::TOP;
   435   if( t2 == Type::TOP ) return Type::TOP;
   437   // x/x == 1 since we always generate the dynamic divisor check for 0.
   438   if( phase->eqv( in(1), in(2) ) )
   439     return TypeInt::ONE;
   441   // Either input is BOTTOM ==> the result is the local BOTTOM
   442   const Type *bot = bottom_type();
   443   if( (t1 == bot) || (t2 == bot) ||
   444       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
   445     return bot;
   447   // Divide the two numbers.  We approximate.
   448   // If divisor is a constant and not zero
   449   const TypeInt *i1 = t1->is_int();
   450   const TypeInt *i2 = t2->is_int();
   451   int widen = MAX2(i1->_widen, i2->_widen);
   453   if( i2->is_con() && i2->get_con() != 0 ) {
   454     int32 d = i2->get_con(); // Divisor
   455     jint lo, hi;
   456     if( d >= 0 ) {
   457       lo = i1->_lo/d;
   458       hi = i1->_hi/d;
   459     } else {
   460       if( d == -1 && i1->_lo == min_jint ) {
   461         // 'min_jint/-1' throws arithmetic exception during compilation
   462         lo = min_jint;
   463         // do not support holes, 'hi' must go to either min_jint or max_jint:
   464         // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint]
   465         hi = i1->_hi == min_jint ? min_jint : max_jint;
   466       } else {
   467         lo = i1->_hi/d;
   468         hi = i1->_lo/d;
   469       }
   470     }
   471     return TypeInt::make(lo, hi, widen);
   472   }
   474   // If the dividend is a constant
   475   if( i1->is_con() ) {
   476     int32 d = i1->get_con();
   477     if( d < 0 ) {
   478       if( d == min_jint ) {
   479         //  (-min_jint) == min_jint == (min_jint / -1)
   480         return TypeInt::make(min_jint, max_jint/2 + 1, widen);
   481       } else {
   482         return TypeInt::make(d, -d, widen);
   483       }
   484     }
   485     return TypeInt::make(-d, d, widen);
   486   }
   488   // Otherwise we give up all hope
   489   return TypeInt::INT;
   490 }
   493 //=============================================================================
   494 //------------------------------Identity---------------------------------------
   495 // If the divisor is 1, we are an identity on the dividend.
   496 Node *DivLNode::Identity( PhaseTransform *phase ) {
   497   return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this;
   498 }
   500 //------------------------------Idealize---------------------------------------
   501 // Dividing by a power of 2 is a shift.
   502 Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) {
   503   if (in(0) && remove_dead_region(phase, can_reshape))  return this;
   504   // Don't bother trying to transform a dead node
   505   if( in(0) && in(0)->is_top() )  return NULL;
   507   const Type *t = phase->type( in(2) );
   508   if( t == TypeLong::ONE )      // Identity?
   509     return NULL;                // Skip it
   511   const TypeLong *tl = t->isa_long();
   512   if( !tl ) return NULL;
   513   if( !tl->is_con() ) return NULL;
   514   jlong l = tl->get_con();      // Get divisor
   516   if (l == 0) return NULL;      // Dividing by zero constant does not idealize
   518   set_req(0,NULL);              // Dividing by a not-zero constant; no faulting
   520   // Dividing by MININT does not optimize as a power-of-2 shift.
   521   if( l == min_jlong ) return NULL;
   523   return transform_long_divide( phase, in(1), l );
   524 }
   526 //------------------------------Value------------------------------------------
   527 // A DivLNode divides its inputs.  The third input is a Control input, used to
   528 // prevent hoisting the divide above an unsafe test.
   529 const Type *DivLNode::Value( PhaseTransform *phase ) const {
   530   // Either input is TOP ==> the result is TOP
   531   const Type *t1 = phase->type( in(1) );
   532   const Type *t2 = phase->type( in(2) );
   533   if( t1 == Type::TOP ) return Type::TOP;
   534   if( t2 == Type::TOP ) return Type::TOP;
   536   // x/x == 1 since we always generate the dynamic divisor check for 0.
   537   if( phase->eqv( in(1), in(2) ) )
   538     return TypeLong::ONE;
   540   // Either input is BOTTOM ==> the result is the local BOTTOM
   541   const Type *bot = bottom_type();
   542   if( (t1 == bot) || (t2 == bot) ||
   543       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
   544     return bot;
   546   // Divide the two numbers.  We approximate.
   547   // If divisor is a constant and not zero
   548   const TypeLong *i1 = t1->is_long();
   549   const TypeLong *i2 = t2->is_long();
   550   int widen = MAX2(i1->_widen, i2->_widen);
   552   if( i2->is_con() && i2->get_con() != 0 ) {
   553     jlong d = i2->get_con();    // Divisor
   554     jlong lo, hi;
   555     if( d >= 0 ) {
   556       lo = i1->_lo/d;
   557       hi = i1->_hi/d;
   558     } else {
   559       if( d == CONST64(-1) && i1->_lo == min_jlong ) {
   560         // 'min_jlong/-1' throws arithmetic exception during compilation
   561         lo = min_jlong;
   562         // do not support holes, 'hi' must go to either min_jlong or max_jlong:
   563         // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong]
   564         hi = i1->_hi == min_jlong ? min_jlong : max_jlong;
   565       } else {
   566         lo = i1->_hi/d;
   567         hi = i1->_lo/d;
   568       }
   569     }
   570     return TypeLong::make(lo, hi, widen);
   571   }
   573   // If the dividend is a constant
   574   if( i1->is_con() ) {
   575     jlong d = i1->get_con();
   576     if( d < 0 ) {
   577       if( d == min_jlong ) {
   578         //  (-min_jlong) == min_jlong == (min_jlong / -1)
   579         return TypeLong::make(min_jlong, max_jlong/2 + 1, widen);
   580       } else {
   581         return TypeLong::make(d, -d, widen);
   582       }
   583     }
   584     return TypeLong::make(-d, d, widen);
   585   }
   587   // Otherwise we give up all hope
   588   return TypeLong::LONG;
   589 }
   592 //=============================================================================
   593 //------------------------------Value------------------------------------------
   594 // An DivFNode divides its inputs.  The third input is a Control input, used to
   595 // prevent hoisting the divide above an unsafe test.
   596 const Type *DivFNode::Value( PhaseTransform *phase ) const {
   597   // Either input is TOP ==> the result is TOP
   598   const Type *t1 = phase->type( in(1) );
   599   const Type *t2 = phase->type( in(2) );
   600   if( t1 == Type::TOP ) return Type::TOP;
   601   if( t2 == Type::TOP ) return Type::TOP;
   603   // Either input is BOTTOM ==> the result is the local BOTTOM
   604   const Type *bot = bottom_type();
   605   if( (t1 == bot) || (t2 == bot) ||
   606       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
   607     return bot;
   609   // x/x == 1, we ignore 0/0.
   610   // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
   611   // Does not work for variables because of NaN's
   612   if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon)
   613     if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN
   614       return TypeF::ONE;
   616   if( t2 == TypeF::ONE )
   617     return t1;
   619   // If divisor is a constant and not zero, divide them numbers
   620   if( t1->base() == Type::FloatCon &&
   621       t2->base() == Type::FloatCon &&
   622       t2->getf() != 0.0 ) // could be negative zero
   623     return TypeF::make( t1->getf()/t2->getf() );
   625   // If the dividend is a constant zero
   626   // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
   627   // Test TypeF::ZERO is not sufficient as it could be negative zero
   629   if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 )
   630     return TypeF::ZERO;
   632   // Otherwise we give up all hope
   633   return Type::FLOAT;
   634 }
   636 //------------------------------isA_Copy---------------------------------------
   637 // Dividing by self is 1.
   638 // If the divisor is 1, we are an identity on the dividend.
   639 Node *DivFNode::Identity( PhaseTransform *phase ) {
   640   return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this;
   641 }
   644 //------------------------------Idealize---------------------------------------
   645 Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
   646   if (in(0) && remove_dead_region(phase, can_reshape))  return this;
   647   // Don't bother trying to transform a dead node
   648   if( in(0) && in(0)->is_top() )  return NULL;
   650   const Type *t2 = phase->type( in(2) );
   651   if( t2 == TypeF::ONE )         // Identity?
   652     return NULL;                // Skip it
   654   const TypeF *tf = t2->isa_float_constant();
   655   if( !tf ) return NULL;
   656   if( tf->base() != Type::FloatCon ) return NULL;
   658   // Check for out of range values
   659   if( tf->is_nan() || !tf->is_finite() ) return NULL;
   661   // Get the value
   662   float f = tf->getf();
   663   int exp;
   665   // Only for special case of dividing by a power of 2
   666   if( frexp((double)f, &exp) != 0.5 ) return NULL;
   668   // Limit the range of acceptable exponents
   669   if( exp < -126 || exp > 126 ) return NULL;
   671   // Compute the reciprocal
   672   float reciprocal = ((float)1.0) / f;
   674   assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
   676   // return multiplication by the reciprocal
   677   return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal))));
   678 }
   680 //=============================================================================
   681 //------------------------------Value------------------------------------------
   682 // An DivDNode divides its inputs.  The third input is a Control input, used to
   683 // prevent hoisting the divide above an unsafe test.
   684 const Type *DivDNode::Value( PhaseTransform *phase ) const {
   685   // Either input is TOP ==> the result is TOP
   686   const Type *t1 = phase->type( in(1) );
   687   const Type *t2 = phase->type( in(2) );
   688   if( t1 == Type::TOP ) return Type::TOP;
   689   if( t2 == Type::TOP ) return Type::TOP;
   691   // Either input is BOTTOM ==> the result is the local BOTTOM
   692   const Type *bot = bottom_type();
   693   if( (t1 == bot) || (t2 == bot) ||
   694       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
   695     return bot;
   697   // x/x == 1, we ignore 0/0.
   698   // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
   699   // Does not work for variables because of NaN's
   700   if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon)
   701     if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN
   702       return TypeD::ONE;
   704   if( t2 == TypeD::ONE )
   705     return t1;
   707   // If divisor is a constant and not zero, divide them numbers
   708   if( t1->base() == Type::DoubleCon &&
   709       t2->base() == Type::DoubleCon &&
   710       t2->getd() != 0.0 ) // could be negative zero
   711     return TypeD::make( t1->getd()/t2->getd() );
   713   // If the dividend is a constant zero
   714   // Note: if t1 and t2 are zero then result is NaN (JVMS page 213)
   715   // Test TypeF::ZERO is not sufficient as it could be negative zero
   716   if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 )
   717     return TypeD::ZERO;
   719   // Otherwise we give up all hope
   720   return Type::DOUBLE;
   721 }
   724 //------------------------------isA_Copy---------------------------------------
   725 // Dividing by self is 1.
   726 // If the divisor is 1, we are an identity on the dividend.
   727 Node *DivDNode::Identity( PhaseTransform *phase ) {
   728   return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this;
   729 }
   731 //------------------------------Idealize---------------------------------------
   732 Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
   733   if (in(0) && remove_dead_region(phase, can_reshape))  return this;
   734   // Don't bother trying to transform a dead node
   735   if( in(0) && in(0)->is_top() )  return NULL;
   737   const Type *t2 = phase->type( in(2) );
   738   if( t2 == TypeD::ONE )         // Identity?
   739     return NULL;                // Skip it
   741   const TypeD *td = t2->isa_double_constant();
   742   if( !td ) return NULL;
   743   if( td->base() != Type::DoubleCon ) return NULL;
   745   // Check for out of range values
   746   if( td->is_nan() || !td->is_finite() ) return NULL;
   748   // Get the value
   749   double d = td->getd();
   750   int exp;
   752   // Only for special case of dividing by a power of 2
   753   if( frexp(d, &exp) != 0.5 ) return NULL;
   755   // Limit the range of acceptable exponents
   756   if( exp < -1021 || exp > 1022 ) return NULL;
   758   // Compute the reciprocal
   759   double reciprocal = 1.0 / d;
   761   assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" );
   763   // return multiplication by the reciprocal
   764   return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal))));
   765 }
   767 //=============================================================================
   768 //------------------------------Idealize---------------------------------------
   769 Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) {
   770   // Check for dead control input
   771   if( in(0) && remove_dead_region(phase, can_reshape) )  return this;
   772   // Don't bother trying to transform a dead node
   773   if( in(0) && in(0)->is_top() )  return NULL;
   775   // Get the modulus
   776   const Type *t = phase->type( in(2) );
   777   if( t == Type::TOP ) return NULL;
   778   const TypeInt *ti = t->is_int();
   780   // Check for useless control input
   781   // Check for excluding mod-zero case
   782   if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) {
   783     set_req(0, NULL);        // Yank control input
   784     return this;
   785   }
   787   // See if we are MOD'ing by 2^k or 2^k-1.
   788   if( !ti->is_con() ) return NULL;
   789   jint con = ti->get_con();
   791   Node *hook = new (phase->C, 1) Node(1);
   793   // First, special check for modulo 2^k-1
   794   if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) {
   795     uint k = exact_log2(con+1);  // Extract k
   797     // Basic algorithm by David Detlefs.  See fastmod_int.java for gory details.
   798     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*/};
   799     int trip_count = 1;
   800     if( k < ARRAY_SIZE(unroll_factor))  trip_count = unroll_factor[k];
   802     // If the unroll factor is not too large, and if conditional moves are
   803     // ok, then use this case
   804     if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
   805       Node *x = in(1);            // Value being mod'd
   806       Node *divisor = in(2);      // Also is mask
   808       hook->init_req(0, x);       // Add a use to x to prevent him from dying
   809       // Generate code to reduce X rapidly to nearly 2^k-1.
   810       for( int i = 0; i < trip_count; i++ ) {
   811         Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) );
   812         Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed
   813         x = phase->transform( new (phase->C, 3) AddINode(xh,xl) );
   814         hook->set_req(0, x);
   815       }
   817       // Generate sign-fixup code.  Was original value positive?
   818       // int hack_res = (i >= 0) ? divisor : 1;
   819       Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) );
   820       Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
   821       Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) );
   822       // if( x >= hack_res ) x -= divisor;
   823       Node *sub  = phase->transform( new (phase->C, 3) SubINode( x, divisor ) );
   824       Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) );
   825       Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
   826       // Convention is to not transform the return value of an Ideal
   827       // since Ideal is expected to return a modified 'this' or a new node.
   828       Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT);
   829       // cmov2 is now the mod
   831       // Now remove the bogus extra edges used to keep things alive
   832       if (can_reshape) {
   833         phase->is_IterGVN()->remove_dead_node(hook);
   834       } else {
   835         hook->set_req(0, NULL);   // Just yank bogus edge during Parse phase
   836       }
   837       return cmov2;
   838     }
   839   }
   841   // Fell thru, the unroll case is not appropriate. Transform the modulo
   842   // into a long multiply/int multiply/subtract case
   844   // Cannot handle mod 0, and min_jint isn't handled by the transform
   845   if( con == 0 || con == min_jint ) return NULL;
   847   // Get the absolute value of the constant; at this point, we can use this
   848   jint pos_con = (con >= 0) ? con : -con;
   850   // integer Mod 1 is always 0
   851   if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO);
   853   int log2_con = -1;
   855   // If this is a power of two, they maybe we can mask it
   856   if( is_power_of_2(pos_con) ) {
   857     log2_con = log2_intptr((intptr_t)pos_con);
   859     const Type *dt = phase->type(in(1));
   860     const TypeInt *dti = dt->isa_int();
   862     // See if this can be masked, if the dividend is non-negative
   863     if( dti && dti->_lo >= 0 )
   864       return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) );
   865   }
   867   // Save in(1) so that it cannot be changed or deleted
   868   hook->init_req(0, in(1));
   870   // Divide using the transform from DivI to MulL
   871   Node *result = transform_int_divide( phase, in(1), pos_con );
   872   if (result != NULL) {
   873     Node *divide = phase->transform(result);
   875     // Re-multiply, using a shift if this is a power of two
   876     Node *mult = NULL;
   878     if( log2_con >= 0 )
   879       mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) );
   880     else
   881       mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) );
   883     // Finally, subtract the multiplied divided value from the original
   884     result = new (phase->C, 3) SubINode( in(1), mult );
   885   }
   887   // Now remove the bogus extra edges used to keep things alive
   888   if (can_reshape) {
   889     phase->is_IterGVN()->remove_dead_node(hook);
   890   } else {
   891     hook->set_req(0, NULL);       // Just yank bogus edge during Parse phase
   892   }
   894   // return the value
   895   return result;
   896 }
   898 //------------------------------Value------------------------------------------
   899 const Type *ModINode::Value( PhaseTransform *phase ) const {
   900   // Either input is TOP ==> the result is TOP
   901   const Type *t1 = phase->type( in(1) );
   902   const Type *t2 = phase->type( in(2) );
   903   if( t1 == Type::TOP ) return Type::TOP;
   904   if( t2 == Type::TOP ) return Type::TOP;
   906   // We always generate the dynamic check for 0.
   907   // 0 MOD X is 0
   908   if( t1 == TypeInt::ZERO ) return TypeInt::ZERO;
   909   // X MOD X is 0
   910   if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO;
   912   // Either input is BOTTOM ==> the result is the local BOTTOM
   913   const Type *bot = bottom_type();
   914   if( (t1 == bot) || (t2 == bot) ||
   915       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
   916     return bot;
   918   const TypeInt *i1 = t1->is_int();
   919   const TypeInt *i2 = t2->is_int();
   920   if( !i1->is_con() || !i2->is_con() ) {
   921     if( i1->_lo >= 0 && i2->_lo >= 0 )
   922       return TypeInt::POS;
   923     // If both numbers are not constants, we know little.
   924     return TypeInt::INT;
   925   }
   926   // Mod by zero?  Throw exception at runtime!
   927   if( !i2->get_con() ) return TypeInt::POS;
   929   // We must be modulo'ing 2 float constants.
   930   // Check for min_jint % '-1', result is defined to be '0'.
   931   if( i1->get_con() == min_jint && i2->get_con() == -1 )
   932     return TypeInt::ZERO;
   934   return TypeInt::make( i1->get_con() % i2->get_con() );
   935 }
   938 //=============================================================================
   939 //------------------------------Idealize---------------------------------------
   940 Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
   941   // Check for dead control input
   942   if( in(0) && remove_dead_region(phase, can_reshape) )  return this;
   943   // Don't bother trying to transform a dead node
   944   if( in(0) && in(0)->is_top() )  return NULL;
   946   // Get the modulus
   947   const Type *t = phase->type( in(2) );
   948   if( t == Type::TOP ) return NULL;
   949   const TypeLong *tl = t->is_long();
   951   // Check for useless control input
   952   // Check for excluding mod-zero case
   953   if( in(0) && (tl->_hi < 0 || tl->_lo > 0) ) {
   954     set_req(0, NULL);        // Yank control input
   955     return this;
   956   }
   958   // See if we are MOD'ing by 2^k or 2^k-1.
   959   if( !tl->is_con() ) return NULL;
   960   jlong con = tl->get_con();
   962   Node *hook = new (phase->C, 1) Node(1);
   964   // Expand mod
   965   if( con >= 0 && con < max_jlong && is_power_of_2_long(con+1) ) {
   966     uint k = log2_long(con);       // Extract k
   968     // Basic algorithm by David Detlefs.  See fastmod_long.java for gory details.
   969     // Used to help a popular random number generator which does a long-mod
   970     // of 2^31-1 and shows up in SpecJBB and SciMark.
   971     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*/};
   972     int trip_count = 1;
   973     if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k];
   975     // If the unroll factor is not too large, and if conditional moves are
   976     // ok, then use this case
   977     if( trip_count <= 5 && ConditionalMoveLimit != 0 ) {
   978       Node *x = in(1);            // Value being mod'd
   979       Node *divisor = in(2);      // Also is mask
   981       hook->init_req(0, x);       // Add a use to x to prevent him from dying
   982       // Generate code to reduce X rapidly to nearly 2^k-1.
   983       for( int i = 0; i < trip_count; i++ ) {
   984         Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) );
   985         Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed
   986         x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) );
   987         hook->set_req(0, x);    // Add a use to x to prevent him from dying
   988       }
   990       // Generate sign-fixup code.  Was original value positive?
   991       // long hack_res = (i >= 0) ? divisor : CONST64(1);
   992       Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) );
   993       Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) );
   994       Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) );
   995       // if( x >= hack_res ) x -= divisor;
   996       Node *sub  = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) );
   997       Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) );
   998       Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) );
   999       // Convention is to not transform the return value of an Ideal
  1000       // since Ideal is expected to return a modified 'this' or a new node.
  1001       Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG);
  1002       // cmov2 is now the mod
  1004       // Now remove the bogus extra edges used to keep things alive
  1005       if (can_reshape) {
  1006         phase->is_IterGVN()->remove_dead_node(hook);
  1007       } else {
  1008         hook->set_req(0, NULL);   // Just yank bogus edge during Parse phase
  1010       return cmov2;
  1014   // Fell thru, the unroll case is not appropriate. Transform the modulo
  1015   // into a long multiply/int multiply/subtract case
  1017   // Cannot handle mod 0, and min_jint isn't handled by the transform
  1018   if( con == 0 || con == min_jlong ) return NULL;
  1020   // Get the absolute value of the constant; at this point, we can use this
  1021   jlong pos_con = (con >= 0) ? con : -con;
  1023   // integer Mod 1 is always 0
  1024   if( pos_con == 1 ) return new (phase->C, 1) ConLNode(TypeLong::ZERO);
  1026   int log2_con = -1;
  1028   // If this is a power of two, they maybe we can mask it
  1029   if( is_power_of_2_long(pos_con) ) {
  1030     log2_con = log2_long(pos_con);
  1032     const Type *dt = phase->type(in(1));
  1033     const TypeLong *dtl = dt->isa_long();
  1035     // See if this can be masked, if the dividend is non-negative
  1036     if( dtl && dtl->_lo >= 0 )
  1037       return ( new (phase->C, 3) AndLNode( in(1), phase->longcon( pos_con-1 ) ) );
  1040   // Save in(1) so that it cannot be changed or deleted
  1041   hook->init_req(0, in(1));
  1043   // Divide using the transform from DivI to MulL
  1044   Node *result = transform_long_divide( phase, in(1), pos_con );
  1045   if (result != NULL) {
  1046     Node *divide = phase->transform(result);
  1048     // Re-multiply, using a shift if this is a power of two
  1049     Node *mult = NULL;
  1051     if( log2_con >= 0 )
  1052       mult = phase->transform( new (phase->C, 3) LShiftLNode( divide, phase->intcon( log2_con ) ) );
  1053     else
  1054       mult = phase->transform( new (phase->C, 3) MulLNode( divide, phase->longcon( pos_con ) ) );
  1056     // Finally, subtract the multiplied divided value from the original
  1057     result = new (phase->C, 3) SubLNode( in(1), mult );
  1060   // Now remove the bogus extra edges used to keep things alive
  1061   if (can_reshape) {
  1062     phase->is_IterGVN()->remove_dead_node(hook);
  1063   } else {
  1064     hook->set_req(0, NULL);       // Just yank bogus edge during Parse phase
  1067   // return the value
  1068   return result;
  1071 //------------------------------Value------------------------------------------
  1072 const Type *ModLNode::Value( PhaseTransform *phase ) const {
  1073   // Either input is TOP ==> the result is TOP
  1074   const Type *t1 = phase->type( in(1) );
  1075   const Type *t2 = phase->type( in(2) );
  1076   if( t1 == Type::TOP ) return Type::TOP;
  1077   if( t2 == Type::TOP ) return Type::TOP;
  1079   // We always generate the dynamic check for 0.
  1080   // 0 MOD X is 0
  1081   if( t1 == TypeLong::ZERO ) return TypeLong::ZERO;
  1082   // X MOD X is 0
  1083   if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO;
  1085   // Either input is BOTTOM ==> the result is the local BOTTOM
  1086   const Type *bot = bottom_type();
  1087   if( (t1 == bot) || (t2 == bot) ||
  1088       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
  1089     return bot;
  1091   const TypeLong *i1 = t1->is_long();
  1092   const TypeLong *i2 = t2->is_long();
  1093   if( !i1->is_con() || !i2->is_con() ) {
  1094     if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) )
  1095       return TypeLong::POS;
  1096     // If both numbers are not constants, we know little.
  1097     return TypeLong::LONG;
  1099   // Mod by zero?  Throw exception at runtime!
  1100   if( !i2->get_con() ) return TypeLong::POS;
  1102   // We must be modulo'ing 2 float constants.
  1103   // Check for min_jint % '-1', result is defined to be '0'.
  1104   if( i1->get_con() == min_jlong && i2->get_con() == -1 )
  1105     return TypeLong::ZERO;
  1107   return TypeLong::make( i1->get_con() % i2->get_con() );
  1111 //=============================================================================
  1112 //------------------------------Value------------------------------------------
  1113 const Type *ModFNode::Value( PhaseTransform *phase ) const {
  1114   // Either input is TOP ==> the result is TOP
  1115   const Type *t1 = phase->type( in(1) );
  1116   const Type *t2 = phase->type( in(2) );
  1117   if( t1 == Type::TOP ) return Type::TOP;
  1118   if( t2 == Type::TOP ) return Type::TOP;
  1120   // Either input is BOTTOM ==> the result is the local BOTTOM
  1121   const Type *bot = bottom_type();
  1122   if( (t1 == bot) || (t2 == bot) ||
  1123       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
  1124     return bot;
  1126   // If either number is not a constant, we know nothing.
  1127   if ((t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon)) {
  1128     return Type::FLOAT;         // note: x%x can be either NaN or 0
  1131   float f1 = t1->getf();
  1132   float f2 = t2->getf();
  1133   jint  x1 = jint_cast(f1);     // note:  *(int*)&f1, not just (int)f1
  1134   jint  x2 = jint_cast(f2);
  1136   // If either is a NaN, return an input NaN
  1137   if (g_isnan(f1))    return t1;
  1138   if (g_isnan(f2))    return t2;
  1140   // If an operand is infinity or the divisor is +/- zero, punt.
  1141   if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jint)
  1142     return Type::FLOAT;
  1144   // We must be modulo'ing 2 float constants.
  1145   // Make sure that the sign of the fmod is equal to the sign of the dividend
  1146   jint xr = jint_cast(fmod(f1, f2));
  1147   if ((x1 ^ xr) < 0) {
  1148     xr ^= min_jint;
  1151   return TypeF::make(jfloat_cast(xr));
  1155 //=============================================================================
  1156 //------------------------------Value------------------------------------------
  1157 const Type *ModDNode::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;
  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;
  1170   // If either number is not a constant, we know nothing.
  1171   if ((t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon)) {
  1172     return Type::DOUBLE;        // note: x%x can be either NaN or 0
  1175   double f1 = t1->getd();
  1176   double f2 = t2->getd();
  1177   jlong  x1 = jlong_cast(f1);   // note:  *(long*)&f1, not just (long)f1
  1178   jlong  x2 = jlong_cast(f2);
  1180   // If either is a NaN, return an input NaN
  1181   if (g_isnan(f1))    return t1;
  1182   if (g_isnan(f2))    return t2;
  1184   // If an operand is infinity or the divisor is +/- zero, punt.
  1185   if (!g_isfinite(f1) || !g_isfinite(f2) || x2 == 0 || x2 == min_jlong)
  1186     return Type::DOUBLE;
  1188   // We must be modulo'ing 2 double constants.
  1189   // Make sure that the sign of the fmod is equal to the sign of the dividend
  1190   jlong xr = jlong_cast(fmod(f1, f2));
  1191   if ((x1 ^ xr) < 0) {
  1192     xr ^= min_jlong;
  1195   return TypeD::make(jdouble_cast(xr));
  1198 //=============================================================================
  1200 DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) {
  1201   init_req(0, c);
  1202   init_req(1, dividend);
  1203   init_req(2, divisor);
  1206 //------------------------------make------------------------------------------
  1207 DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) {
  1208   Node* n = div_or_mod;
  1209   assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI,
  1210          "only div or mod input pattern accepted");
  1212   DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2));
  1213   Node*        dproj  = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
  1214   Node*        mproj  = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
  1215   return divmod;
  1218 //------------------------------make------------------------------------------
  1219 DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) {
  1220   Node* n = div_or_mod;
  1221   assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL,
  1222          "only div or mod input pattern accepted");
  1224   DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2));
  1225   Node*        dproj  = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num);
  1226   Node*        mproj  = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num);
  1227   return divmod;
  1230 //------------------------------match------------------------------------------
  1231 // return result(s) along with their RegMask info
  1232 Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) {
  1233   uint ideal_reg = proj->ideal_reg();
  1234   RegMask rm;
  1235   if (proj->_con == div_proj_num) {
  1236     rm = match->divI_proj_mask();
  1237   } else {
  1238     assert(proj->_con == mod_proj_num, "must be div or mod projection");
  1239     rm = match->modI_proj_mask();
  1241   return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);
  1245 //------------------------------match------------------------------------------
  1246 // return result(s) along with their RegMask info
  1247 Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) {
  1248   uint ideal_reg = proj->ideal_reg();
  1249   RegMask rm;
  1250   if (proj->_con == div_proj_num) {
  1251     rm = match->divL_proj_mask();
  1252   } else {
  1253     assert(proj->_con == mod_proj_num, "must be div or mod projection");
  1254     rm = match->modL_proj_mask();
  1256   return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg);

mercurial