diff -r 000000000000 -r a61af66fc99e src/share/vm/opto/divnode.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/opto/divnode.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,1031 @@ +/* + * 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); +}