/* * Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * */ // Portions of code courtesy of Clifford Click // Optimization - Graph Style #include "incls/_precompiled.incl" #include "incls/_divnode.cpp.incl" #include // Implement the integer constant divide -> long multiply transform found in // "Division by Invariant Integers using Multiplication" // by Granlund and Montgomery static Node *transform_int_divide_to_long_multiply( PhaseGVN *phase, Node *dividend, int divisor ) { // Check for invalid divisors assert( divisor != 0 && divisor != min_jint && divisor != 1, "bad divisor for transforming to long multiply" ); // Compute l = ceiling(log2(d)) // presumes d is more likely small bool d_pos = divisor >= 0; int d = d_pos ? divisor : -divisor; unsigned ud = (unsigned)d; const int N = 32; int l = log2_intptr(d-1)+1; int sh_post = l; const uint64_t U1 = (uint64_t)1; // Cliff pointed out how to prevent overflow (from the paper) uint64_t m_low = (((U1 << l) - ud) << N) / ud + (U1 << N); uint64_t m_high = ((((U1 << l) - ud) << N) + (U1 << (l+1))) / ud + (U1 << N); // Reduce to lowest terms for ( ; sh_post > 0; sh_post-- ) { uint64_t m_low_1 = m_low >> 1; uint64_t m_high_1 = m_high >> 1; if ( m_low_1 >= m_high_1 ) break; m_low = m_low_1; m_high = m_high_1; } // Result Node *q; // division by +/- 1 if (d == 1) { // Filtered out as identity above if (d_pos) return NULL; // Just negate the value else { q = new (phase->C, 3) SubINode(phase->intcon(0), dividend); } } // division by +/- a power of 2 else if ( is_power_of_2(d) ) { // See if we can simply do a shift without rounding bool needs_rounding = true; const Type *dt = phase->type(dividend); const TypeInt *dti = dt->isa_int(); // we don't need to round a positive dividend if (dti && dti->_lo >= 0) needs_rounding = false; // An AND mask of sufficient size clears the low bits and // I can avoid rounding. else if( dividend->Opcode() == Op_AndI ) { const TypeInt *andconi = phase->type( dividend->in(2) )->isa_int(); if( andconi && andconi->is_con(-d) ) { dividend = dividend->in(1); needs_rounding = false; } } // Add rounding to the shift to handle the sign bit if( needs_rounding ) { Node *t1 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(l - 1))); Node *t2 = phase->transform(new (phase->C, 3) URShiftINode(t1, phase->intcon(N - l))); dividend = phase->transform(new (phase->C, 3) AddINode(dividend, t2)); } q = new (phase->C, 3) RShiftINode(dividend, phase->intcon(l)); if (!d_pos) q = new (phase->C, 3) SubINode(phase->intcon(0), phase->transform(q)); } // division by something else else if (m_high < (U1 << (N-1))) { Node *t1 = phase->transform(new (phase->C, 2) ConvI2LNode(dividend)); Node *t2 = phase->transform(new (phase->C, 3) MulLNode(t1, phase->longcon(m_high))); Node *t3 = phase->transform(new (phase->C, 3) RShiftLNode(t2, phase->intcon(sh_post+N))); Node *t4 = phase->transform(new (phase->C, 2) ConvL2INode(t3)); Node *t5 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1))); q = new (phase->C, 3) SubINode(d_pos ? t4 : t5, d_pos ? t5 : t4); } // This handles that case where m_high is >= 2**(N-1). In that case, // we subtract out 2**N from the multiply and add it in later as // "dividend" in the equation (t5). This case computes the same result // as the immediately preceeding case, save that rounding and overflow // are accounted for. else { Node *t1 = phase->transform(new (phase->C, 2) ConvI2LNode(dividend)); Node *t2 = phase->transform(new (phase->C, 3) MulLNode(t1, phase->longcon(m_high - (U1 << N)))); Node *t3 = phase->transform(new (phase->C, 3) RShiftLNode(t2, phase->intcon(N))); Node *t4 = phase->transform(new (phase->C, 2) ConvL2INode(t3)); Node *t5 = phase->transform(new (phase->C, 3) AddINode(dividend, t4)); Node *t6 = phase->transform(new (phase->C, 3) RShiftINode(t5, phase->intcon(sh_post))); Node *t7 = phase->transform(new (phase->C, 3) RShiftINode(dividend, phase->intcon(N-1))); q = new (phase->C, 3) SubINode(d_pos ? t6 : t7, d_pos ? t7 : t6); } return (q); } //============================================================================= //------------------------------Identity--------------------------------------- // If the divisor is 1, we are an identity on the dividend. Node *DivINode::Identity( PhaseTransform *phase ) { return (phase->type( in(2) )->higher_equal(TypeInt::ONE)) ? in(1) : this; } //------------------------------Idealize--------------------------------------- // Divides can be changed to multiplies and/or shifts Node *DivINode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; const Type *t = phase->type( in(2) ); if( t == TypeInt::ONE ) // Identity? return NULL; // Skip it const TypeInt *ti = t->isa_int(); if( !ti ) return NULL; if( !ti->is_con() ) return NULL; int i = ti->get_con(); // Get divisor if (i == 0) return NULL; // Dividing by zero constant does not idealize set_req(0,NULL); // Dividing by a not-zero constant; no faulting // Dividing by MININT does not optimize as a power-of-2 shift. if( i == min_jint ) return NULL; return transform_int_divide_to_long_multiply( phase, in(1), i ); } //------------------------------Value------------------------------------------ // A DivINode divides its inputs. The third input is a Control input, used to // prevent hoisting the divide above an unsafe test. const Type *DivINode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // x/x == 1 since we always generate the dynamic divisor check for 0. if( phase->eqv( in(1), in(2) ) ) return TypeInt::ONE; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // Divide the two numbers. We approximate. // If divisor is a constant and not zero const TypeInt *i1 = t1->is_int(); const TypeInt *i2 = t2->is_int(); int widen = MAX2(i1->_widen, i2->_widen); if( i2->is_con() && i2->get_con() != 0 ) { int32 d = i2->get_con(); // Divisor jint lo, hi; if( d >= 0 ) { lo = i1->_lo/d; hi = i1->_hi/d; } else { if( d == -1 && i1->_lo == min_jint ) { // 'min_jint/-1' throws arithmetic exception during compilation lo = min_jint; // do not support holes, 'hi' must go to either min_jint or max_jint: // [min_jint, -10]/[-1,-1] ==> [min_jint] UNION [10,max_jint] hi = i1->_hi == min_jint ? min_jint : max_jint; } else { lo = i1->_hi/d; hi = i1->_lo/d; } } return TypeInt::make(lo, hi, widen); } // If the dividend is a constant if( i1->is_con() ) { int32 d = i1->get_con(); if( d < 0 ) { if( d == min_jint ) { // (-min_jint) == min_jint == (min_jint / -1) return TypeInt::make(min_jint, max_jint/2 + 1, widen); } else { return TypeInt::make(d, -d, widen); } } return TypeInt::make(-d, d, widen); } // Otherwise we give up all hope return TypeInt::INT; } //============================================================================= //------------------------------Identity--------------------------------------- // If the divisor is 1, we are an identity on the dividend. Node *DivLNode::Identity( PhaseTransform *phase ) { return (phase->type( in(2) )->higher_equal(TypeLong::ONE)) ? in(1) : this; } //------------------------------Idealize--------------------------------------- // Dividing by a power of 2 is a shift. Node *DivLNode::Ideal( PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; const Type *t = phase->type( in(2) ); if( t == TypeLong::ONE ) // Identity? return NULL; // Skip it const TypeLong *ti = t->isa_long(); if( !ti ) return NULL; if( !ti->is_con() ) return NULL; jlong i = ti->get_con(); // Get divisor if( i ) set_req(0, NULL); // Dividing by a not-zero constant; no faulting // Dividing by MININT does not optimize as a power-of-2 shift. if( i == min_jlong ) return NULL; // Check for negative power of 2 divisor, if so, negate it and set a flag // to indicate result needs to be negated. Note that negating the dividend // here does not work when it has the value MININT Node *dividend = in(1); bool negate_res = false; if (is_power_of_2_long(-i)) { i = -i; // Flip divisor negate_res = true; } // Check for power of 2 if (!is_power_of_2_long(i)) // Is divisor a power of 2? return NULL; // Not a power of 2 // Compute number of bits to shift int log_i = log2_long(i); // See if we can simply do a shift without rounding bool needs_rounding = true; const Type *dt = phase->type(dividend); const TypeLong *dtl = dt->isa_long(); if (dtl && dtl->_lo > 0) { // we don't need to round a positive dividend needs_rounding = false; } else if( dividend->Opcode() == Op_AndL ) { // An AND mask of sufficient size clears the low bits and // I can avoid rounding. const TypeLong *andconi = phase->type( dividend->in(2) )->isa_long(); if( andconi && andconi->is_con() && andconi->get_con() == -i ) { dividend = dividend->in(1); needs_rounding = false; } } if (!needs_rounding) { Node *result = new (phase->C, 3) RShiftLNode(dividend, phase->intcon(log_i)); if (negate_res) { result = phase->transform(result); result = new (phase->C, 3) SubLNode(phase->longcon(0), result); } return result; } // Divide-by-power-of-2 can be made into a shift, but you have to do // more math for the rounding. You need to add 0 for positive // numbers, and "i-1" for negative numbers. Example: i=4, so the // shift is by 2. You need to add 3 to negative dividends and 0 to // positive ones. So (-7+3)>>2 becomes -1, (-4+3)>>2 becomes -1, // (-2+3)>>2 becomes 0, etc. // Compute 0 or -1, based on sign bit Node *sign = phase->transform(new (phase->C, 3) RShiftLNode(dividend,phase->intcon(63))); // Mask sign bit to the low sign bits Node *round = phase->transform(new (phase->C, 3) AndLNode(sign,phase->longcon(i-1))); // Round up before shifting Node *sum = phase->transform(new (phase->C, 3) AddLNode(dividend,round)); // Shift for division Node *result = new (phase->C, 3) RShiftLNode(sum, phase->intcon(log_i)); if (negate_res) { result = phase->transform(result); result = new (phase->C, 3) SubLNode(phase->longcon(0), result); } return result; } //------------------------------Value------------------------------------------ // A DivLNode divides its inputs. The third input is a Control input, used to // prevent hoisting the divide above an unsafe test. const Type *DivLNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // x/x == 1 since we always generate the dynamic divisor check for 0. if( phase->eqv( in(1), in(2) ) ) return TypeLong::ONE; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // Divide the two numbers. We approximate. // If divisor is a constant and not zero const TypeLong *i1 = t1->is_long(); const TypeLong *i2 = t2->is_long(); int widen = MAX2(i1->_widen, i2->_widen); if( i2->is_con() && i2->get_con() != 0 ) { jlong d = i2->get_con(); // Divisor jlong lo, hi; if( d >= 0 ) { lo = i1->_lo/d; hi = i1->_hi/d; } else { if( d == CONST64(-1) && i1->_lo == min_jlong ) { // 'min_jlong/-1' throws arithmetic exception during compilation lo = min_jlong; // do not support holes, 'hi' must go to either min_jlong or max_jlong: // [min_jlong, -10]/[-1,-1] ==> [min_jlong] UNION [10,max_jlong] hi = i1->_hi == min_jlong ? min_jlong : max_jlong; } else { lo = i1->_hi/d; hi = i1->_lo/d; } } return TypeLong::make(lo, hi, widen); } // If the dividend is a constant if( i1->is_con() ) { jlong d = i1->get_con(); if( d < 0 ) { if( d == min_jlong ) { // (-min_jlong) == min_jlong == (min_jlong / -1) return TypeLong::make(min_jlong, max_jlong/2 + 1, widen); } else { return TypeLong::make(d, -d, widen); } } return TypeLong::make(-d, d, widen); } // Otherwise we give up all hope return TypeLong::LONG; } //============================================================================= //------------------------------Value------------------------------------------ // An DivFNode divides its inputs. The third input is a Control input, used to // prevent hoisting the divide above an unsafe test. const Type *DivFNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // x/x == 1, we ignore 0/0. // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) // does not work for variables because of NaN's if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon) if (!g_isnan(t1->getf()) && g_isfinite(t1->getf()) && t1->getf() != 0.0) // could be negative ZERO or NaN return TypeF::ONE; if( t2 == TypeF::ONE ) return t1; // If divisor is a constant and not zero, divide them numbers if( t1->base() == Type::FloatCon && t2->base() == Type::FloatCon && t2->getf() != 0.0 ) // could be negative zero return TypeF::make( t1->getf()/t2->getf() ); // If the dividend is a constant zero // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) // Test TypeF::ZERO is not sufficient as it could be negative zero if( t1 == TypeF::ZERO && !g_isnan(t2->getf()) && t2->getf() != 0.0 ) return TypeF::ZERO; // Otherwise we give up all hope return Type::FLOAT; } //------------------------------isA_Copy--------------------------------------- // Dividing by self is 1. // If the divisor is 1, we are an identity on the dividend. Node *DivFNode::Identity( PhaseTransform *phase ) { return (phase->type( in(2) ) == TypeF::ONE) ? in(1) : this; } //------------------------------Idealize--------------------------------------- Node *DivFNode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; const Type *t2 = phase->type( in(2) ); if( t2 == TypeF::ONE ) // Identity? return NULL; // Skip it const TypeF *tf = t2->isa_float_constant(); if( !tf ) return NULL; if( tf->base() != Type::FloatCon ) return NULL; // Check for out of range values if( tf->is_nan() || !tf->is_finite() ) return NULL; // Get the value float f = tf->getf(); int exp; // Only for special case of dividing by a power of 2 if( frexp((double)f, &exp) != 0.5 ) return NULL; // Limit the range of acceptable exponents if( exp < -126 || exp > 126 ) return NULL; // Compute the reciprocal float reciprocal = ((float)1.0) / f; assert( frexp((double)reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); // return multiplication by the reciprocal return (new (phase->C, 3) MulFNode(in(1), phase->makecon(TypeF::make(reciprocal)))); } //============================================================================= //------------------------------Value------------------------------------------ // An DivDNode divides its inputs. The third input is a Control input, used to // prvent hoisting the divide above an unsafe test. const Type *DivDNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // x/x == 1, we ignore 0/0. // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) // Does not work for variables because of NaN's if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon) if (!g_isnan(t1->getd()) && g_isfinite(t1->getd()) && t1->getd() != 0.0) // could be negative ZERO or NaN return TypeD::ONE; if( t2 == TypeD::ONE ) return t1; // If divisor is a constant and not zero, divide them numbers if( t1->base() == Type::DoubleCon && t2->base() == Type::DoubleCon && t2->getd() != 0.0 ) // could be negative zero return TypeD::make( t1->getd()/t2->getd() ); // If the dividend is a constant zero // Note: if t1 and t2 are zero then result is NaN (JVMS page 213) // Test TypeF::ZERO is not sufficient as it could be negative zero if( t1 == TypeD::ZERO && !g_isnan(t2->getd()) && t2->getd() != 0.0 ) return TypeD::ZERO; // Otherwise we give up all hope return Type::DOUBLE; } //------------------------------isA_Copy--------------------------------------- // Dividing by self is 1. // If the divisor is 1, we are an identity on the dividend. Node *DivDNode::Identity( PhaseTransform *phase ) { return (phase->type( in(2) ) == TypeD::ONE) ? in(1) : this; } //------------------------------Idealize--------------------------------------- Node *DivDNode::Ideal(PhaseGVN *phase, bool can_reshape) { if (in(0) && remove_dead_region(phase, can_reshape)) return this; const Type *t2 = phase->type( in(2) ); if( t2 == TypeD::ONE ) // Identity? return NULL; // Skip it const TypeD *td = t2->isa_double_constant(); if( !td ) return NULL; if( td->base() != Type::DoubleCon ) return NULL; // Check for out of range values if( td->is_nan() || !td->is_finite() ) return NULL; // Get the value double d = td->getd(); int exp; // Only for special case of dividing by a power of 2 if( frexp(d, &exp) != 0.5 ) return NULL; // Limit the range of acceptable exponents if( exp < -1021 || exp > 1022 ) return NULL; // Compute the reciprocal double reciprocal = 1.0 / d; assert( frexp(reciprocal, &exp) == 0.5, "reciprocal should be power of 2" ); // return multiplication by the reciprocal return (new (phase->C, 3) MulDNode(in(1), phase->makecon(TypeD::make(reciprocal)))); } //============================================================================= //------------------------------Idealize--------------------------------------- Node *ModINode::Ideal(PhaseGVN *phase, bool can_reshape) { // Check for dead control input if( remove_dead_region(phase, can_reshape) ) return this; // Get the modulus const Type *t = phase->type( in(2) ); if( t == Type::TOP ) return NULL; const TypeInt *ti = t->is_int(); // Check for useless control input // Check for excluding mod-zero case if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) { set_req(0, NULL); // Yank control input return this; } // See if we are MOD'ing by 2^k or 2^k-1. if( !ti->is_con() ) return NULL; jint con = ti->get_con(); Node *hook = new (phase->C, 1) Node(1); // First, special check for modulo 2^k-1 if( con >= 0 && con < max_jint && is_power_of_2(con+1) ) { uint k = exact_log2(con+1); // Extract k // Basic algorithm by David Detlefs. See fastmod_int.java for gory details. 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*/}; int trip_count = 1; if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; // If the unroll factor is not too large, and if conditional moves are // ok, then use this case if( trip_count <= 5 && ConditionalMoveLimit != 0 ) { Node *x = in(1); // Value being mod'd Node *divisor = in(2); // Also is mask hook->init_req(0, x); // Add a use to x to prevent him from dying // Generate code to reduce X rapidly to nearly 2^k-1. for( int i = 0; i < trip_count; i++ ) { Node *xl = phase->transform( new (phase->C, 3) AndINode(x,divisor) ); Node *xh = phase->transform( new (phase->C, 3) RShiftINode(x,phase->intcon(k)) ); // Must be signed x = phase->transform( new (phase->C, 3) AddINode(xh,xl) ); hook->set_req(0, x); } // Generate sign-fixup code. Was original value positive? // int hack_res = (i >= 0) ? divisor : 1; Node *cmp1 = phase->transform( new (phase->C, 3) CmpINode( in(1), phase->intcon(0) ) ); Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) ); Node *cmov1= phase->transform( new (phase->C, 4) CMoveINode(bol1, phase->intcon(1), divisor, TypeInt::POS) ); // if( x >= hack_res ) x -= divisor; Node *sub = phase->transform( new (phase->C, 3) SubINode( x, divisor ) ); Node *cmp2 = phase->transform( new (phase->C, 3) CmpINode( x, cmov1 ) ); Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) ); // Convention is to not transform the return value of an Ideal // since Ideal is expected to return a modified 'this' or a new node. Node *cmov2= new (phase->C, 4) CMoveINode(bol2, x, sub, TypeInt::INT); // cmov2 is now the mod // Now remove the bogus extra edges used to keep things alive if (can_reshape) { phase->is_IterGVN()->remove_dead_node(hook); } else { hook->set_req(0, NULL); // Just yank bogus edge during Parse phase } return cmov2; } } // Fell thru, the unroll case is not appropriate. Transform the modulo // into a long multiply/int multiply/subtract case // Cannot handle mod 0, and min_jint isn't handled by the transform if( con == 0 || con == min_jint ) return NULL; // Get the absolute value of the constant; at this point, we can use this jint pos_con = (con >= 0) ? con : -con; // integer Mod 1 is always 0 if( pos_con == 1 ) return new (phase->C, 1) ConINode(TypeInt::ZERO); int log2_con = -1; // If this is a power of two, they maybe we can mask it if( is_power_of_2(pos_con) ) { log2_con = log2_intptr((intptr_t)pos_con); const Type *dt = phase->type(in(1)); const TypeInt *dti = dt->isa_int(); // See if this can be masked, if the dividend is non-negative if( dti && dti->_lo >= 0 ) return ( new (phase->C, 3) AndINode( in(1), phase->intcon( pos_con-1 ) ) ); } // Save in(1) so that it cannot be changed or deleted hook->init_req(0, in(1)); // Divide using the transform from DivI to MulL Node *divide = phase->transform( transform_int_divide_to_long_multiply( phase, in(1), pos_con ) ); // Re-multiply, using a shift if this is a power of two Node *mult = NULL; if( log2_con >= 0 ) mult = phase->transform( new (phase->C, 3) LShiftINode( divide, phase->intcon( log2_con ) ) ); else mult = phase->transform( new (phase->C, 3) MulINode( divide, phase->intcon( pos_con ) ) ); // Finally, subtract the multiplied divided value from the original Node *result = new (phase->C, 3) SubINode( in(1), mult ); // Now remove the bogus extra edges used to keep things alive if (can_reshape) { phase->is_IterGVN()->remove_dead_node(hook); } else { hook->set_req(0, NULL); // Just yank bogus edge during Parse phase } // return the value return result; } //------------------------------Value------------------------------------------ const Type *ModINode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // We always generate the dynamic check for 0. // 0 MOD X is 0 if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; // X MOD X is 0 if( phase->eqv( in(1), in(2) ) ) return TypeInt::ZERO; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; const TypeInt *i1 = t1->is_int(); const TypeInt *i2 = t2->is_int(); if( !i1->is_con() || !i2->is_con() ) { if( i1->_lo >= 0 && i2->_lo >= 0 ) return TypeInt::POS; // If both numbers are not constants, we know little. return TypeInt::INT; } // Mod by zero? Throw exception at runtime! if( !i2->get_con() ) return TypeInt::POS; // We must be modulo'ing 2 float constants. // Check for min_jint % '-1', result is defined to be '0'. if( i1->get_con() == min_jint && i2->get_con() == -1 ) return TypeInt::ZERO; return TypeInt::make( i1->get_con() % i2->get_con() ); } //============================================================================= //------------------------------Idealize--------------------------------------- Node *ModLNode::Ideal(PhaseGVN *phase, bool can_reshape) { // Check for dead control input if( remove_dead_region(phase, can_reshape) ) return this; // Get the modulus const Type *t = phase->type( in(2) ); if( t == Type::TOP ) return NULL; const TypeLong *ti = t->is_long(); // Check for useless control input // Check for excluding mod-zero case if( in(0) && (ti->_hi < 0 || ti->_lo > 0) ) { set_req(0, NULL); // Yank control input return this; } // See if we are MOD'ing by 2^k or 2^k-1. if( !ti->is_con() ) return NULL; jlong con = ti->get_con(); bool m1 = false; if( !is_power_of_2_long(con) ) { // Not 2^k if( !is_power_of_2_long(con+1) ) // Not 2^k-1? return NULL; // No interesting mod hacks m1 = true; // Found 2^k-1 con++; // Convert to 2^k form } uint k = log2_long(con); // Extract k // Expand mod if( !m1 ) { // Case 2^k } else { // Case 2^k-1 // Basic algorithm by David Detlefs. See fastmod_long.java for gory details. // Used to help a popular random number generator which does a long-mod // of 2^31-1 and shows up in SpecJBB and SciMark. 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*/}; int trip_count = 1; if( k < ARRAY_SIZE(unroll_factor)) trip_count = unroll_factor[k]; if( trip_count > 4 ) return NULL; // Too much unrolling if (ConditionalMoveLimit == 0) return NULL; // cmov is required Node *x = in(1); // Value being mod'd Node *divisor = in(2); // Also is mask Node *hook = new (phase->C, 1) Node(x); // Generate code to reduce X rapidly to nearly 2^k-1. for( int i = 0; i < trip_count; i++ ) { Node *xl = phase->transform( new (phase->C, 3) AndLNode(x,divisor) ); Node *xh = phase->transform( new (phase->C, 3) RShiftLNode(x,phase->intcon(k)) ); // Must be signed x = phase->transform( new (phase->C, 3) AddLNode(xh,xl) ); hook->set_req(0, x); // Add a use to x to prevent him from dying } // Generate sign-fixup code. Was original value positive? // long hack_res = (i >= 0) ? divisor : CONST64(1); Node *cmp1 = phase->transform( new (phase->C, 3) CmpLNode( in(1), phase->longcon(0) ) ); Node *bol1 = phase->transform( new (phase->C, 2) BoolNode( cmp1, BoolTest::ge ) ); Node *cmov1= phase->transform( new (phase->C, 4) CMoveLNode(bol1, phase->longcon(1), divisor, TypeLong::LONG) ); // if( x >= hack_res ) x -= divisor; Node *sub = phase->transform( new (phase->C, 3) SubLNode( x, divisor ) ); Node *cmp2 = phase->transform( new (phase->C, 3) CmpLNode( x, cmov1 ) ); Node *bol2 = phase->transform( new (phase->C, 2) BoolNode( cmp2, BoolTest::ge ) ); // Convention is to not transform the return value of an Ideal // since Ideal is expected to return a modified 'this' or a new node. Node *cmov2= new (phase->C, 4) CMoveLNode(bol2, x, sub, TypeLong::LONG); // cmov2 is now the mod // Now remove the bogus extra edges used to keep things alive if (can_reshape) { phase->is_IterGVN()->remove_dead_node(hook); } else { hook->set_req(0, NULL); // Just yank bogus edge during Parse phase } return cmov2; } return NULL; } //------------------------------Value------------------------------------------ const Type *ModLNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // We always generate the dynamic check for 0. // 0 MOD X is 0 if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; // X MOD X is 0 if( phase->eqv( in(1), in(2) ) ) return TypeLong::ZERO; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; const TypeLong *i1 = t1->is_long(); const TypeLong *i2 = t2->is_long(); if( !i1->is_con() || !i2->is_con() ) { if( i1->_lo >= CONST64(0) && i2->_lo >= CONST64(0) ) return TypeLong::POS; // If both numbers are not constants, we know little. return TypeLong::LONG; } // Mod by zero? Throw exception at runtime! if( !i2->get_con() ) return TypeLong::POS; // We must be modulo'ing 2 float constants. // Check for min_jint % '-1', result is defined to be '0'. if( i1->get_con() == min_jlong && i2->get_con() == -1 ) return TypeLong::ZERO; return TypeLong::make( i1->get_con() % i2->get_con() ); } //============================================================================= //------------------------------Value------------------------------------------ const Type *ModFNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // If either is a NaN, return an input NaN if( g_isnan(t1->getf()) ) return t1; if( g_isnan(t2->getf()) ) return t2; // It is not worth trying to constant fold this stuff! return Type::FLOAT; /* // If dividend is infinity or divisor is zero, or both, the result is NaN if( !g_isfinite(t1->getf()) || ((t2->getf() == 0.0) || (jint_cast(t2->getf()) == 0x80000000)) ) // X MOD infinity = X if( !g_isfinite(t2->getf()) && !g_isnan(t2->getf()) ) return t1; // 0 MOD finite = dividend (positive or negative zero) // Not valid for: NaN MOD any; any MOD nan; 0 MOD 0; or for 0 MOD NaN // NaNs are handled previously. if( !(t2->getf() == 0.0) && !((int)t2->getf() == 0x80000000)) { if (((t1->getf() == 0.0) || ((int)t1->getf() == 0x80000000)) && g_isfinite(t2->getf()) ) { return t1; } } // X MOD X is 0 // Does not work for variables because of NaN's if( phase->eqv( in(1), in(2) ) && t1->base() == Type::FloatCon) if (!g_isnan(t1->getf()) && (t1->getf() != 0.0) && ((int)t1->getf() != 0x80000000)) { if(t1->getf() < 0.0) { float result = jfloat_cast(0x80000000); return TypeF::make( result ); } else return TypeF::ZERO; } // If both numbers are not constants, we know nothing. if( (t1->base() != Type::FloatCon) || (t2->base() != Type::FloatCon) ) return Type::FLOAT; // We must be modulo'ing 2 float constants. // Make sure that the sign of the fmod is equal to the sign of the dividend float result = (float)fmod( t1->getf(), t2->getf() ); float dividend = t1->getf(); if( (dividend < 0.0) || ((int)dividend == 0x80000000) ) { if( result > 0.0 ) result = 0.0 - result; else if( result == 0.0 ) { result = jfloat_cast(0x80000000); } } return TypeF::make( result ); */ } //============================================================================= //------------------------------Value------------------------------------------ const Type *ModDNode::Value( PhaseTransform *phase ) const { // Either input is TOP ==> the result is TOP const Type *t1 = phase->type( in(1) ); const Type *t2 = phase->type( in(2) ); if( t1 == Type::TOP ) return Type::TOP; if( t2 == Type::TOP ) return Type::TOP; // Either input is BOTTOM ==> the result is the local BOTTOM const Type *bot = bottom_type(); if( (t1 == bot) || (t2 == bot) || (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) return bot; // If either is a NaN, return an input NaN if( g_isnan(t1->getd()) ) return t1; if( g_isnan(t2->getd()) ) return t2; // X MOD infinity = X if( !g_isfinite(t2->getd())) return t1; // 0 MOD finite = dividend (positive or negative zero) // Not valid for: NaN MOD any; any MOD nan; 0 MOD 0; or for 0 MOD NaN // NaNs are handled previously. if( !(t2->getd() == 0.0) ) { if( t1->getd() == 0.0 && g_isfinite(t2->getd()) ) { return t1; } } // X MOD X is 0 // does not work for variables because of NaN's if( phase->eqv( in(1), in(2) ) && t1->base() == Type::DoubleCon ) if (!g_isnan(t1->getd()) && t1->getd() != 0.0) return TypeD::ZERO; // If both numbers are not constants, we know nothing. if( (t1->base() != Type::DoubleCon) || (t2->base() != Type::DoubleCon) ) return Type::DOUBLE; // We must be modulo'ing 2 double constants. return TypeD::make( fmod( t1->getd(), t2->getd() ) ); } //============================================================================= DivModNode::DivModNode( Node *c, Node *dividend, Node *divisor ) : MultiNode(3) { init_req(0, c); init_req(1, dividend); init_req(2, divisor); } //------------------------------make------------------------------------------ DivModINode* DivModINode::make(Compile* C, Node* div_or_mod) { Node* n = div_or_mod; assert(n->Opcode() == Op_DivI || n->Opcode() == Op_ModI, "only div or mod input pattern accepted"); DivModINode* divmod = new (C, 3) DivModINode(n->in(0), n->in(1), n->in(2)); Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num); Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num); return divmod; } //------------------------------make------------------------------------------ DivModLNode* DivModLNode::make(Compile* C, Node* div_or_mod) { Node* n = div_or_mod; assert(n->Opcode() == Op_DivL || n->Opcode() == Op_ModL, "only div or mod input pattern accepted"); DivModLNode* divmod = new (C, 3) DivModLNode(n->in(0), n->in(1), n->in(2)); Node* dproj = new (C, 1) ProjNode(divmod, DivModNode::div_proj_num); Node* mproj = new (C, 1) ProjNode(divmod, DivModNode::mod_proj_num); return divmod; } //------------------------------match------------------------------------------ // return result(s) along with their RegMask info Node *DivModINode::match( const ProjNode *proj, const Matcher *match ) { uint ideal_reg = proj->ideal_reg(); RegMask rm; if (proj->_con == div_proj_num) { rm = match->divI_proj_mask(); } else { assert(proj->_con == mod_proj_num, "must be div or mod projection"); rm = match->modI_proj_mask(); } return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg); } //------------------------------match------------------------------------------ // return result(s) along with their RegMask info Node *DivModLNode::match( const ProjNode *proj, const Matcher *match ) { uint ideal_reg = proj->ideal_reg(); RegMask rm; if (proj->_con == div_proj_num) { rm = match->divL_proj_mask(); } else { assert(proj->_con == mod_proj_num, "must be div or mod projection"); rm = match->modL_proj_mask(); } return new (match->C, 1)MachProjNode(this, proj->_con, rm, ideal_reg); }