| /* |
| * Copyright (c) 1997, 2012, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "opto/addnode.hpp" |
| #include "opto/connode.hpp" |
| #include "opto/memnode.hpp" |
| #include "opto/mulnode.hpp" |
| #include "opto/phaseX.hpp" |
| #include "opto/subnode.hpp" |
| |
| // Portions of code courtesy of Clifford Click |
| |
| |
| //============================================================================= |
| //------------------------------hash------------------------------------------- |
| // Hash function over MulNodes. Needs to be commutative; i.e., I swap |
| // (commute) inputs to MulNodes willy-nilly so the hash function must return |
| // the same value in the presence of edge swapping. |
| uint MulNode::hash() const { |
| return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode(); |
| } |
| |
| //------------------------------Identity--------------------------------------- |
| // Multiplying a one preserves the other argument |
| Node *MulNode::Identity( PhaseTransform *phase ) { |
| register const Type *one = mul_id(); // The multiplicative identity |
| if( phase->type( in(1) )->higher_equal( one ) ) return in(2); |
| if( phase->type( in(2) )->higher_equal( one ) ) return in(1); |
| |
| return this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| // We also canonicalize the Node, moving constants to the right input, |
| // and flatten expressions (so that 1+x+2 becomes x+3). |
| Node *MulNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| Node *progress = NULL; // Progress flag |
| // We are OK if right is a constant, or right is a load and |
| // left is a non-constant. |
| if( !(t2->singleton() || |
| (in(2)->is_Load() && !(t1->singleton() || in(1)->is_Load())) ) ) { |
| if( t1->singleton() || // Left input is a constant? |
| // Otherwise, sort inputs (commutativity) to help value numbering. |
| (in(1)->_idx > in(2)->_idx) ) { |
| swap_edges(1, 2); |
| const Type *t = t1; |
| t1 = t2; |
| t2 = t; |
| progress = this; // Made progress |
| } |
| } |
| |
| // If the right input is a constant, and the left input is a product of a |
| // constant, flatten the expression tree. |
| uint op = Opcode(); |
| if( t2->singleton() && // Right input is a constant? |
| op != Op_MulF && // Float & double cannot reassociate |
| op != Op_MulD ) { |
| if( t2 == Type::TOP ) return NULL; |
| Node *mul1 = in(1); |
| #ifdef ASSERT |
| // Check for dead loop |
| int op1 = mul1->Opcode(); |
| if( phase->eqv( mul1, this ) || phase->eqv( in(2), this ) || |
| ( op1 == mul_opcode() || op1 == add_opcode() ) && |
| ( phase->eqv( mul1->in(1), this ) || phase->eqv( mul1->in(2), this ) || |
| phase->eqv( mul1->in(1), mul1 ) || phase->eqv( mul1->in(2), mul1 ) ) ) |
| assert(false, "dead loop in MulNode::Ideal"); |
| #endif |
| |
| if( mul1->Opcode() == mul_opcode() ) { // Left input is a multiply? |
| // Mul of a constant? |
| const Type *t12 = phase->type( mul1->in(2) ); |
| if( t12->singleton() && t12 != Type::TOP) { // Left input is an add of a constant? |
| // Compute new constant; check for overflow |
| const Type *tcon01 = ((MulNode*)mul1)->mul_ring(t2,t12); |
| if( tcon01->singleton() ) { |
| // The Mul of the flattened expression |
| set_req(1, mul1->in(1)); |
| set_req(2, phase->makecon( tcon01 )); |
| t2 = tcon01; |
| progress = this; // Made progress |
| } |
| } |
| } |
| // If the right input is a constant, and the left input is an add of a |
| // constant, flatten the tree: (X+con1)*con0 ==> X*con0 + con1*con0 |
| const Node *add1 = in(1); |
| if( add1->Opcode() == add_opcode() ) { // Left input is an add? |
| // Add of a constant? |
| const Type *t12 = phase->type( add1->in(2) ); |
| if( t12->singleton() && t12 != Type::TOP ) { // Left input is an add of a constant? |
| assert( add1->in(1) != add1, "dead loop in MulNode::Ideal" ); |
| // Compute new constant; check for overflow |
| const Type *tcon01 = mul_ring(t2,t12); |
| if( tcon01->singleton() ) { |
| |
| // Convert (X+con1)*con0 into X*con0 |
| Node *mul = clone(); // mul = ()*con0 |
| mul->set_req(1,add1->in(1)); // mul = X*con0 |
| mul = phase->transform(mul); |
| |
| Node *add2 = add1->clone(); |
| add2->set_req(1, mul); // X*con0 + con0*con1 |
| add2->set_req(2, phase->makecon(tcon01) ); |
| progress = add2; |
| } |
| } |
| } // End of is left input an add |
| } // End of is right input a Mul |
| |
| return progress; |
| } |
| |
| //------------------------------Value----------------------------------------- |
| const Type *MulNode::Value( PhaseTransform *phase ) const { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Either input is ZERO ==> the result is ZERO. |
| // Not valid for floats or doubles since +0.0 * -0.0 --> +0.0 |
| int op = Opcode(); |
| if( op == Op_MulI || op == Op_AndI || op == Op_MulL || op == Op_AndL ) { |
| const Type *zero = add_id(); // The multiplicative zero |
| if( t1->higher_equal( zero ) ) return zero; |
| if( t2->higher_equal( zero ) ) return zero; |
| } |
| |
| // Either input is BOTTOM ==> the result is the local BOTTOM |
| if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) |
| return bottom_type(); |
| |
| #if defined(IA32) |
| // Can't trust native compilers to properly fold strict double |
| // multiplication with round-to-zero on this platform. |
| if (op == Op_MulD && phase->C->method()->is_strict()) { |
| return TypeD::DOUBLE; |
| } |
| #endif |
| |
| return mul_ring(t1,t2); // Local flavor of type multiplication |
| } |
| |
| |
| //============================================================================= |
| //------------------------------Ideal------------------------------------------ |
| // Check for power-of-2 multiply, then try the regular MulNode::Ideal |
| Node *MulINode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| // Swap constant to right |
| jint con; |
| if ((con = in(1)->find_int_con(0)) != 0) { |
| swap_edges(1, 2); |
| // Finish rest of method to use info in 'con' |
| } else if ((con = in(2)->find_int_con(0)) == 0) { |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| |
| // Now we have a constant Node on the right and the constant in con |
| if( con == 0 ) return NULL; // By zero is handled by Value call |
| if( con == 1 ) return NULL; // By one is handled by Identity call |
| |
| // Check for negative constant; if so negate the final result |
| bool sign_flip = false; |
| if( con < 0 ) { |
| con = -con; |
| sign_flip = true; |
| } |
| |
| // Get low bit; check for being the only bit |
| Node *res = NULL; |
| jint bit1 = con & -con; // Extract low bit |
| if( bit1 == con ) { // Found a power of 2? |
| res = new (phase->C) LShiftINode( in(1), phase->intcon(log2_intptr(bit1)) ); |
| } else { |
| |
| // Check for constant with 2 bits set |
| jint bit2 = con-bit1; |
| bit2 = bit2 & -bit2; // Extract 2nd bit |
| if( bit2 + bit1 == con ) { // Found all bits in con? |
| Node *n1 = phase->transform( new (phase->C) LShiftINode( in(1), phase->intcon(log2_intptr(bit1)) ) ); |
| Node *n2 = phase->transform( new (phase->C) LShiftINode( in(1), phase->intcon(log2_intptr(bit2)) ) ); |
| res = new (phase->C) AddINode( n2, n1 ); |
| |
| } else if (is_power_of_2(con+1)) { |
| // Sleezy: power-of-2 -1. Next time be generic. |
| jint temp = (jint) (con + 1); |
| Node *n1 = phase->transform( new (phase->C) LShiftINode( in(1), phase->intcon(log2_intptr(temp)) ) ); |
| res = new (phase->C) SubINode( n1, in(1) ); |
| } else { |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| } |
| |
| if( sign_flip ) { // Need to negate result? |
| res = phase->transform(res);// Transform, before making the zero con |
| res = new (phase->C) SubINode(phase->intcon(0),res); |
| } |
| |
| return res; // Return final result |
| } |
| |
| //------------------------------mul_ring--------------------------------------- |
| // Compute the product type of two integer ranges into this node. |
| const Type *MulINode::mul_ring(const Type *t0, const Type *t1) const { |
| const TypeInt *r0 = t0->is_int(); // Handy access |
| const TypeInt *r1 = t1->is_int(); |
| |
| // Fetch endpoints of all ranges |
| int32 lo0 = r0->_lo; |
| double a = (double)lo0; |
| int32 hi0 = r0->_hi; |
| double b = (double)hi0; |
| int32 lo1 = r1->_lo; |
| double c = (double)lo1; |
| int32 hi1 = r1->_hi; |
| double d = (double)hi1; |
| |
| // Compute all endpoints & check for overflow |
| int32 A = lo0*lo1; |
| if( (double)A != a*c ) return TypeInt::INT; // Overflow? |
| int32 B = lo0*hi1; |
| if( (double)B != a*d ) return TypeInt::INT; // Overflow? |
| int32 C = hi0*lo1; |
| if( (double)C != b*c ) return TypeInt::INT; // Overflow? |
| int32 D = hi0*hi1; |
| if( (double)D != b*d ) return TypeInt::INT; // Overflow? |
| |
| if( A < B ) { lo0 = A; hi0 = B; } // Sort range endpoints |
| else { lo0 = B; hi0 = A; } |
| if( C < D ) { |
| if( C < lo0 ) lo0 = C; |
| if( D > hi0 ) hi0 = D; |
| } else { |
| if( D < lo0 ) lo0 = D; |
| if( C > hi0 ) hi0 = C; |
| } |
| return TypeInt::make(lo0, hi0, MAX2(r0->_widen,r1->_widen)); |
| } |
| |
| |
| //============================================================================= |
| //------------------------------Ideal------------------------------------------ |
| // Check for power-of-2 multiply, then try the regular MulNode::Ideal |
| Node *MulLNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| // Swap constant to right |
| jlong con; |
| if ((con = in(1)->find_long_con(0)) != 0) { |
| swap_edges(1, 2); |
| // Finish rest of method to use info in 'con' |
| } else if ((con = in(2)->find_long_con(0)) == 0) { |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| |
| // Now we have a constant Node on the right and the constant in con |
| if( con == CONST64(0) ) return NULL; // By zero is handled by Value call |
| if( con == CONST64(1) ) return NULL; // By one is handled by Identity call |
| |
| // Check for negative constant; if so negate the final result |
| bool sign_flip = false; |
| if( con < 0 ) { |
| con = -con; |
| sign_flip = true; |
| } |
| |
| // Get low bit; check for being the only bit |
| Node *res = NULL; |
| jlong bit1 = con & -con; // Extract low bit |
| if( bit1 == con ) { // Found a power of 2? |
| res = new (phase->C) LShiftLNode( in(1), phase->intcon(log2_long(bit1)) ); |
| } else { |
| |
| // Check for constant with 2 bits set |
| jlong bit2 = con-bit1; |
| bit2 = bit2 & -bit2; // Extract 2nd bit |
| if( bit2 + bit1 == con ) { // Found all bits in con? |
| Node *n1 = phase->transform( new (phase->C) LShiftLNode( in(1), phase->intcon(log2_long(bit1)) ) ); |
| Node *n2 = phase->transform( new (phase->C) LShiftLNode( in(1), phase->intcon(log2_long(bit2)) ) ); |
| res = new (phase->C) AddLNode( n2, n1 ); |
| |
| } else if (is_power_of_2_long(con+1)) { |
| // Sleezy: power-of-2 -1. Next time be generic. |
| jlong temp = (jlong) (con + 1); |
| Node *n1 = phase->transform( new (phase->C) LShiftLNode( in(1), phase->intcon(log2_long(temp)) ) ); |
| res = new (phase->C) SubLNode( n1, in(1) ); |
| } else { |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| } |
| |
| if( sign_flip ) { // Need to negate result? |
| res = phase->transform(res);// Transform, before making the zero con |
| res = new (phase->C) SubLNode(phase->longcon(0),res); |
| } |
| |
| return res; // Return final result |
| } |
| |
| //------------------------------mul_ring--------------------------------------- |
| // Compute the product type of two integer ranges into this node. |
| const Type *MulLNode::mul_ring(const Type *t0, const Type *t1) const { |
| const TypeLong *r0 = t0->is_long(); // Handy access |
| const TypeLong *r1 = t1->is_long(); |
| |
| // Fetch endpoints of all ranges |
| jlong lo0 = r0->_lo; |
| double a = (double)lo0; |
| jlong hi0 = r0->_hi; |
| double b = (double)hi0; |
| jlong lo1 = r1->_lo; |
| double c = (double)lo1; |
| jlong hi1 = r1->_hi; |
| double d = (double)hi1; |
| |
| // Compute all endpoints & check for overflow |
| jlong A = lo0*lo1; |
| if( (double)A != a*c ) return TypeLong::LONG; // Overflow? |
| jlong B = lo0*hi1; |
| if( (double)B != a*d ) return TypeLong::LONG; // Overflow? |
| jlong C = hi0*lo1; |
| if( (double)C != b*c ) return TypeLong::LONG; // Overflow? |
| jlong D = hi0*hi1; |
| if( (double)D != b*d ) return TypeLong::LONG; // Overflow? |
| |
| if( A < B ) { lo0 = A; hi0 = B; } // Sort range endpoints |
| else { lo0 = B; hi0 = A; } |
| if( C < D ) { |
| if( C < lo0 ) lo0 = C; |
| if( D > hi0 ) hi0 = D; |
| } else { |
| if( D < lo0 ) lo0 = D; |
| if( C > hi0 ) hi0 = C; |
| } |
| return TypeLong::make(lo0, hi0, MAX2(r0->_widen,r1->_widen)); |
| } |
| |
| //============================================================================= |
| //------------------------------mul_ring--------------------------------------- |
| // Compute the product type of two double ranges into this node. |
| const Type *MulFNode::mul_ring(const Type *t0, const Type *t1) const { |
| if( t0 == Type::FLOAT || t1 == Type::FLOAT ) return Type::FLOAT; |
| return TypeF::make( t0->getf() * t1->getf() ); |
| } |
| |
| //============================================================================= |
| //------------------------------mul_ring--------------------------------------- |
| // Compute the product type of two double ranges into this node. |
| const Type *MulDNode::mul_ring(const Type *t0, const Type *t1) const { |
| if( t0 == Type::DOUBLE || t1 == Type::DOUBLE ) return Type::DOUBLE; |
| // We must be multiplying 2 double constants. |
| return TypeD::make( t0->getd() * t1->getd() ); |
| } |
| |
| //============================================================================= |
| //------------------------------Value------------------------------------------ |
| const Type *MulHiLNode::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; |
| |
| // It is not worth trying to constant fold this stuff! |
| return TypeLong::LONG; |
| } |
| |
| //============================================================================= |
| //------------------------------mul_ring--------------------------------------- |
| // Supplied function returns the product of the inputs IN THE CURRENT RING. |
| // For the logical operations the ring's MUL is really a logical AND function. |
| // This also type-checks the inputs for sanity. Guaranteed never to |
| // be passed a TOP or BOTTOM type, these are filtered out by pre-check. |
| const Type *AndINode::mul_ring( const Type *t0, const Type *t1 ) const { |
| const TypeInt *r0 = t0->is_int(); // Handy access |
| const TypeInt *r1 = t1->is_int(); |
| int widen = MAX2(r0->_widen,r1->_widen); |
| |
| // If either input is a constant, might be able to trim cases |
| if( !r0->is_con() && !r1->is_con() ) |
| return TypeInt::INT; // No constants to be had |
| |
| // Both constants? Return bits |
| if( r0->is_con() && r1->is_con() ) |
| return TypeInt::make( r0->get_con() & r1->get_con() ); |
| |
| if( r0->is_con() && r0->get_con() > 0 ) |
| return TypeInt::make(0, r0->get_con(), widen); |
| |
| if( r1->is_con() && r1->get_con() > 0 ) |
| return TypeInt::make(0, r1->get_con(), widen); |
| |
| if( r0 == TypeInt::BOOL || r1 == TypeInt::BOOL ) { |
| return TypeInt::BOOL; |
| } |
| |
| return TypeInt::INT; // No constants to be had |
| } |
| |
| //------------------------------Identity--------------------------------------- |
| // Masking off the high bits of an unsigned load is not required |
| Node *AndINode::Identity( PhaseTransform *phase ) { |
| |
| // x & x => x |
| if (phase->eqv(in(1), in(2))) return in(1); |
| |
| Node* in1 = in(1); |
| uint op = in1->Opcode(); |
| const TypeInt* t2 = phase->type(in(2))->isa_int(); |
| if (t2 && t2->is_con()) { |
| int con = t2->get_con(); |
| // Masking off high bits which are always zero is useless. |
| const TypeInt* t1 = phase->type( in(1) )->isa_int(); |
| if (t1 != NULL && t1->_lo >= 0) { |
| jint t1_support = right_n_bits(1 + log2_intptr(t1->_hi)); |
| if ((t1_support & con) == t1_support) |
| return in1; |
| } |
| // Masking off the high bits of a unsigned-shift-right is not |
| // needed either. |
| if (op == Op_URShiftI) { |
| const TypeInt* t12 = phase->type(in1->in(2))->isa_int(); |
| if (t12 && t12->is_con()) { // Shift is by a constant |
| int shift = t12->get_con(); |
| shift &= BitsPerJavaInteger - 1; // semantics of Java shifts |
| int mask = max_juint >> shift; |
| if ((mask & con) == mask) // If AND is useless, skip it |
| return in1; |
| } |
| } |
| } |
| return MulNode::Identity(phase); |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| Node *AndINode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| // Special case constant AND mask |
| const TypeInt *t2 = phase->type( in(2) )->isa_int(); |
| if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape); |
| const int mask = t2->get_con(); |
| Node *load = in(1); |
| uint lop = load->Opcode(); |
| |
| // Masking bits off of a Character? Hi bits are already zero. |
| if( lop == Op_LoadUS && |
| (mask & 0xFFFF0000) ) // Can we make a smaller mask? |
| return new (phase->C) AndINode(load,phase->intcon(mask&0xFFFF)); |
| |
| // Masking bits off of a Short? Loading a Character does some masking |
| if (can_reshape && |
| load->outcnt() == 1 && load->unique_out() == this) { |
| if (lop == Op_LoadS && (mask & 0xFFFF0000) == 0 ) { |
| Node *ldus = new (phase->C) LoadUSNode(load->in(MemNode::Control), |
| load->in(MemNode::Memory), |
| load->in(MemNode::Address), |
| load->adr_type(), |
| TypeInt::CHAR, MemNode::unordered); |
| ldus = phase->transform(ldus); |
| return new (phase->C) AndINode(ldus, phase->intcon(mask & 0xFFFF)); |
| } |
| |
| // Masking sign bits off of a Byte? Do an unsigned byte load plus |
| // an and. |
| if (lop == Op_LoadB && (mask & 0xFFFFFF00) == 0) { |
| Node* ldub = new (phase->C) LoadUBNode(load->in(MemNode::Control), |
| load->in(MemNode::Memory), |
| load->in(MemNode::Address), |
| load->adr_type(), |
| TypeInt::UBYTE, MemNode::unordered); |
| ldub = phase->transform(ldub); |
| return new (phase->C) AndINode(ldub, phase->intcon(mask)); |
| } |
| } |
| |
| // Masking off sign bits? Dont make them! |
| if( lop == Op_RShiftI ) { |
| const TypeInt *t12 = phase->type(load->in(2))->isa_int(); |
| if( t12 && t12->is_con() ) { // Shift is by a constant |
| int shift = t12->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| const int sign_bits_mask = ~right_n_bits(BitsPerJavaInteger - shift); |
| // If the AND'ing of the 2 masks has no bits, then only original shifted |
| // bits survive. NO sign-extension bits survive the maskings. |
| if( (sign_bits_mask & mask) == 0 ) { |
| // Use zero-fill shift instead |
| Node *zshift = phase->transform(new (phase->C) URShiftINode(load->in(1),load->in(2))); |
| return new (phase->C) AndINode( zshift, in(2) ); |
| } |
| } |
| } |
| |
| // Check for 'negate/and-1', a pattern emitted when someone asks for |
| // 'mod 2'. Negate leaves the low order bit unchanged (think: complement |
| // plus 1) and the mask is of the low order bit. Skip the negate. |
| if( lop == Op_SubI && mask == 1 && load->in(1) && |
| phase->type(load->in(1)) == TypeInt::ZERO ) |
| return new (phase->C) AndINode( load->in(2), in(2) ); |
| |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| |
| //============================================================================= |
| //------------------------------mul_ring--------------------------------------- |
| // Supplied function returns the product of the inputs IN THE CURRENT RING. |
| // For the logical operations the ring's MUL is really a logical AND function. |
| // This also type-checks the inputs for sanity. Guaranteed never to |
| // be passed a TOP or BOTTOM type, these are filtered out by pre-check. |
| const Type *AndLNode::mul_ring( const Type *t0, const Type *t1 ) const { |
| const TypeLong *r0 = t0->is_long(); // Handy access |
| const TypeLong *r1 = t1->is_long(); |
| int widen = MAX2(r0->_widen,r1->_widen); |
| |
| // If either input is a constant, might be able to trim cases |
| if( !r0->is_con() && !r1->is_con() ) |
| return TypeLong::LONG; // No constants to be had |
| |
| // Both constants? Return bits |
| if( r0->is_con() && r1->is_con() ) |
| return TypeLong::make( r0->get_con() & r1->get_con() ); |
| |
| if( r0->is_con() && r0->get_con() > 0 ) |
| return TypeLong::make(CONST64(0), r0->get_con(), widen); |
| |
| if( r1->is_con() && r1->get_con() > 0 ) |
| return TypeLong::make(CONST64(0), r1->get_con(), widen); |
| |
| return TypeLong::LONG; // No constants to be had |
| } |
| |
| //------------------------------Identity--------------------------------------- |
| // Masking off the high bits of an unsigned load is not required |
| Node *AndLNode::Identity( PhaseTransform *phase ) { |
| |
| // x & x => x |
| if (phase->eqv(in(1), in(2))) return in(1); |
| |
| Node *usr = in(1); |
| const TypeLong *t2 = phase->type( in(2) )->isa_long(); |
| if( t2 && t2->is_con() ) { |
| jlong con = t2->get_con(); |
| // Masking off high bits which are always zero is useless. |
| const TypeLong* t1 = phase->type( in(1) )->isa_long(); |
| if (t1 != NULL && t1->_lo >= 0) { |
| jlong t1_support = ((jlong)1 << (1 + log2_long(t1->_hi))) - 1; |
| if ((t1_support & con) == t1_support) |
| return usr; |
| } |
| uint lop = usr->Opcode(); |
| // Masking off the high bits of a unsigned-shift-right is not |
| // needed either. |
| if( lop == Op_URShiftL ) { |
| const TypeInt *t12 = phase->type( usr->in(2) )->isa_int(); |
| if( t12 && t12->is_con() ) { // Shift is by a constant |
| int shift = t12->get_con(); |
| shift &= BitsPerJavaLong - 1; // semantics of Java shifts |
| jlong mask = max_julong >> shift; |
| if( (mask&con) == mask ) // If AND is useless, skip it |
| return usr; |
| } |
| } |
| } |
| return MulNode::Identity(phase); |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| Node *AndLNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| // Special case constant AND mask |
| const TypeLong *t2 = phase->type( in(2) )->isa_long(); |
| if( !t2 || !t2->is_con() ) return MulNode::Ideal(phase, can_reshape); |
| const jlong mask = t2->get_con(); |
| |
| Node* in1 = in(1); |
| uint op = in1->Opcode(); |
| |
| // Are we masking a long that was converted from an int with a mask |
| // that fits in 32-bits? Commute them and use an AndINode. Don't |
| // convert masks which would cause a sign extension of the integer |
| // value. This check includes UI2L masks (0x00000000FFFFFFFF) which |
| // would be optimized away later in Identity. |
| if (op == Op_ConvI2L && (mask & CONST64(0xFFFFFFFF80000000)) == 0) { |
| Node* andi = new (phase->C) AndINode(in1->in(1), phase->intcon(mask)); |
| andi = phase->transform(andi); |
| return new (phase->C) ConvI2LNode(andi); |
| } |
| |
| // Masking off sign bits? Dont make them! |
| if (op == Op_RShiftL) { |
| const TypeInt* t12 = phase->type(in1->in(2))->isa_int(); |
| if( t12 && t12->is_con() ) { // Shift is by a constant |
| int shift = t12->get_con(); |
| shift &= BitsPerJavaLong - 1; // semantics of Java shifts |
| const jlong sign_bits_mask = ~(((jlong)CONST64(1) << (jlong)(BitsPerJavaLong - shift)) -1); |
| // If the AND'ing of the 2 masks has no bits, then only original shifted |
| // bits survive. NO sign-extension bits survive the maskings. |
| if( (sign_bits_mask & mask) == 0 ) { |
| // Use zero-fill shift instead |
| Node *zshift = phase->transform(new (phase->C) URShiftLNode(in1->in(1), in1->in(2))); |
| return new (phase->C) AndLNode(zshift, in(2)); |
| } |
| } |
| } |
| |
| return MulNode::Ideal(phase, can_reshape); |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *LShiftINode::Identity( PhaseTransform *phase ) { |
| const TypeInt *ti = phase->type( in(2) )->isa_int(); // shift count is an int |
| return ( ti && ti->is_con() && ( ti->get_con() & ( BitsPerInt - 1 ) ) == 0 ) ? in(1) : this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| // If the right input is a constant, and the left input is an add of a |
| // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0 |
| Node *LShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| const Type *t = phase->type( in(2) ); |
| if( t == Type::TOP ) return NULL; // Right input is dead |
| const TypeInt *t2 = t->isa_int(); |
| if( !t2 || !t2->is_con() ) return NULL; // Right input is a constant |
| const int con = t2->get_con() & ( BitsPerInt - 1 ); // masked shift count |
| |
| if ( con == 0 ) return NULL; // let Identity() handle 0 shift count |
| |
| // Left input is an add of a constant? |
| Node *add1 = in(1); |
| int add1_op = add1->Opcode(); |
| if( add1_op == Op_AddI ) { // Left input is an add? |
| assert( add1 != add1->in(1), "dead loop in LShiftINode::Ideal" ); |
| const TypeInt *t12 = phase->type(add1->in(2))->isa_int(); |
| if( t12 && t12->is_con() ){ // Left input is an add of a con? |
| // Transform is legal, but check for profit. Avoid breaking 'i2s' |
| // and 'i2b' patterns which typically fold into 'StoreC/StoreB'. |
| if( con < 16 ) { |
| // Compute X << con0 |
| Node *lsh = phase->transform( new (phase->C) LShiftINode( add1->in(1), in(2) ) ); |
| // Compute X<<con0 + (con1<<con0) |
| return new (phase->C) AddINode( lsh, phase->intcon(t12->get_con() << con)); |
| } |
| } |
| } |
| |
| // Check for "(x>>c0)<<c0" which just masks off low bits |
| if( (add1_op == Op_RShiftI || add1_op == Op_URShiftI ) && |
| add1->in(2) == in(2) ) |
| // Convert to "(x & -(1<<c0))" |
| return new (phase->C) AndINode(add1->in(1),phase->intcon( -(1<<con))); |
| |
| // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits |
| if( add1_op == Op_AndI ) { |
| Node *add2 = add1->in(1); |
| int add2_op = add2->Opcode(); |
| if( (add2_op == Op_RShiftI || add2_op == Op_URShiftI ) && |
| add2->in(2) == in(2) ) { |
| // Convert to "(x & (Y<<c0))" |
| Node *y_sh = phase->transform( new (phase->C) LShiftINode( add1->in(2), in(2) ) ); |
| return new (phase->C) AndINode( add2->in(1), y_sh ); |
| } |
| } |
| |
| // Check for ((x & ((1<<(32-c0))-1)) << c0) which ANDs off high bits |
| // before shifting them away. |
| const jint bits_mask = right_n_bits(BitsPerJavaInteger-con); |
| if( add1_op == Op_AndI && |
| phase->type(add1->in(2)) == TypeInt::make( bits_mask ) ) |
| return new (phase->C) LShiftINode( add1->in(1), in(2) ); |
| |
| return NULL; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A LShiftINode shifts its input2 left by input1 amount. |
| const Type *LShiftINode::Value( PhaseTransform *phase ) const { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if( (t1 == TypeInt::INT) || (t2 == TypeInt::INT) || |
| (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) |
| return TypeInt::INT; |
| |
| const TypeInt *r1 = t1->is_int(); // Handy access |
| const TypeInt *r2 = t2->is_int(); // Handy access |
| |
| if (!r2->is_con()) |
| return TypeInt::INT; |
| |
| uint shift = r2->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| // Shift by a multiple of 32 does nothing: |
| if (shift == 0) return t1; |
| |
| // If the shift is a constant, shift the bounds of the type, |
| // unless this could lead to an overflow. |
| if (!r1->is_con()) { |
| jint lo = r1->_lo, hi = r1->_hi; |
| if (((lo << shift) >> shift) == lo && |
| ((hi << shift) >> shift) == hi) { |
| // No overflow. The range shifts up cleanly. |
| return TypeInt::make((jint)lo << (jint)shift, |
| (jint)hi << (jint)shift, |
| MAX2(r1->_widen,r2->_widen)); |
| } |
| return TypeInt::INT; |
| } |
| |
| return TypeInt::make( (jint)r1->get_con() << (jint)shift ); |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *LShiftLNode::Identity( PhaseTransform *phase ) { |
| const TypeInt *ti = phase->type( in(2) )->isa_int(); // shift count is an int |
| return ( ti && ti->is_con() && ( ti->get_con() & ( BitsPerLong - 1 ) ) == 0 ) ? in(1) : this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| // If the right input is a constant, and the left input is an add of a |
| // constant, flatten the tree: (X+con1)<<con0 ==> X<<con0 + con1<<con0 |
| Node *LShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| const Type *t = phase->type( in(2) ); |
| if( t == Type::TOP ) return NULL; // Right input is dead |
| const TypeInt *t2 = t->isa_int(); |
| if( !t2 || !t2->is_con() ) return NULL; // Right input is a constant |
| const int con = t2->get_con() & ( BitsPerLong - 1 ); // masked shift count |
| |
| if ( con == 0 ) return NULL; // let Identity() handle 0 shift count |
| |
| // Left input is an add of a constant? |
| Node *add1 = in(1); |
| int add1_op = add1->Opcode(); |
| if( add1_op == Op_AddL ) { // Left input is an add? |
| // Avoid dead data cycles from dead loops |
| assert( add1 != add1->in(1), "dead loop in LShiftLNode::Ideal" ); |
| const TypeLong *t12 = phase->type(add1->in(2))->isa_long(); |
| if( t12 && t12->is_con() ){ // Left input is an add of a con? |
| // Compute X << con0 |
| Node *lsh = phase->transform( new (phase->C) LShiftLNode( add1->in(1), in(2) ) ); |
| // Compute X<<con0 + (con1<<con0) |
| return new (phase->C) AddLNode( lsh, phase->longcon(t12->get_con() << con)); |
| } |
| } |
| |
| // Check for "(x>>c0)<<c0" which just masks off low bits |
| if( (add1_op == Op_RShiftL || add1_op == Op_URShiftL ) && |
| add1->in(2) == in(2) ) |
| // Convert to "(x & -(1<<c0))" |
| return new (phase->C) AndLNode(add1->in(1),phase->longcon( -(CONST64(1)<<con))); |
| |
| // Check for "((x>>c0) & Y)<<c0" which just masks off more low bits |
| if( add1_op == Op_AndL ) { |
| Node *add2 = add1->in(1); |
| int add2_op = add2->Opcode(); |
| if( (add2_op == Op_RShiftL || add2_op == Op_URShiftL ) && |
| add2->in(2) == in(2) ) { |
| // Convert to "(x & (Y<<c0))" |
| Node *y_sh = phase->transform( new (phase->C) LShiftLNode( add1->in(2), in(2) ) ); |
| return new (phase->C) AndLNode( add2->in(1), y_sh ); |
| } |
| } |
| |
| // Check for ((x & ((CONST64(1)<<(64-c0))-1)) << c0) which ANDs off high bits |
| // before shifting them away. |
| const jlong bits_mask = ((jlong)CONST64(1) << (jlong)(BitsPerJavaLong - con)) - CONST64(1); |
| if( add1_op == Op_AndL && |
| phase->type(add1->in(2)) == TypeLong::make( bits_mask ) ) |
| return new (phase->C) LShiftLNode( add1->in(1), in(2) ); |
| |
| return NULL; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A LShiftLNode shifts its input2 left by input1 amount. |
| const Type *LShiftLNode::Value( PhaseTransform *phase ) const { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if( (t1 == TypeLong::LONG) || (t2 == TypeInt::INT) || |
| (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) |
| return TypeLong::LONG; |
| |
| const TypeLong *r1 = t1->is_long(); // Handy access |
| const TypeInt *r2 = t2->is_int(); // Handy access |
| |
| if (!r2->is_con()) |
| return TypeLong::LONG; |
| |
| uint shift = r2->get_con(); |
| shift &= BitsPerJavaLong - 1; // semantics of Java shifts |
| // Shift by a multiple of 64 does nothing: |
| if (shift == 0) return t1; |
| |
| // If the shift is a constant, shift the bounds of the type, |
| // unless this could lead to an overflow. |
| if (!r1->is_con()) { |
| jlong lo = r1->_lo, hi = r1->_hi; |
| if (((lo << shift) >> shift) == lo && |
| ((hi << shift) >> shift) == hi) { |
| // No overflow. The range shifts up cleanly. |
| return TypeLong::make((jlong)lo << (jint)shift, |
| (jlong)hi << (jint)shift, |
| MAX2(r1->_widen,r2->_widen)); |
| } |
| return TypeLong::LONG; |
| } |
| |
| return TypeLong::make( (jlong)r1->get_con() << (jint)shift ); |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *RShiftINode::Identity( PhaseTransform *phase ) { |
| const TypeInt *t2 = phase->type(in(2))->isa_int(); |
| if( !t2 ) return this; |
| if ( t2->is_con() && ( t2->get_con() & ( BitsPerInt - 1 ) ) == 0 ) |
| return in(1); |
| |
| // Check for useless sign-masking |
| if( in(1)->Opcode() == Op_LShiftI && |
| in(1)->req() == 3 && |
| in(1)->in(2) == in(2) && |
| t2->is_con() ) { |
| uint shift = t2->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| // Compute masks for which this shifting doesn't change |
| int lo = (-1 << (BitsPerJavaInteger - shift-1)); // FFFF8000 |
| int hi = ~lo; // 00007FFF |
| const TypeInt *t11 = phase->type(in(1)->in(1))->isa_int(); |
| if( !t11 ) return this; |
| // Does actual value fit inside of mask? |
| if( lo <= t11->_lo && t11->_hi <= hi ) |
| return in(1)->in(1); // Then shifting is a nop |
| } |
| |
| return this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| Node *RShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| // Inputs may be TOP if they are dead. |
| const TypeInt *t1 = phase->type( in(1) )->isa_int(); |
| if( !t1 ) return NULL; // Left input is an integer |
| const TypeInt *t2 = phase->type( in(2) )->isa_int(); |
| if( !t2 || !t2->is_con() ) return NULL; // Right input is a constant |
| const TypeInt *t3; // type of in(1).in(2) |
| int shift = t2->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| |
| if ( shift == 0 ) return NULL; // let Identity() handle 0 shift count |
| |
| // Check for (x & 0xFF000000) >> 24, whose mask can be made smaller. |
| // Such expressions arise normally from shift chains like (byte)(x >> 24). |
| const Node *mask = in(1); |
| if( mask->Opcode() == Op_AndI && |
| (t3 = phase->type(mask->in(2))->isa_int()) && |
| t3->is_con() ) { |
| Node *x = mask->in(1); |
| jint maskbits = t3->get_con(); |
| // Convert to "(x >> shift) & (mask >> shift)" |
| Node *shr_nomask = phase->transform( new (phase->C) RShiftINode(mask->in(1), in(2)) ); |
| return new (phase->C) AndINode(shr_nomask, phase->intcon( maskbits >> shift)); |
| } |
| |
| // Check for "(short[i] <<16)>>16" which simply sign-extends |
| const Node *shl = in(1); |
| if( shl->Opcode() != Op_LShiftI ) return NULL; |
| |
| if( shift == 16 && |
| (t3 = phase->type(shl->in(2))->isa_int()) && |
| t3->is_con(16) ) { |
| Node *ld = shl->in(1); |
| if( ld->Opcode() == Op_LoadS ) { |
| // Sign extension is just useless here. Return a RShiftI of zero instead |
| // returning 'ld' directly. We cannot return an old Node directly as |
| // that is the job of 'Identity' calls and Identity calls only work on |
| // direct inputs ('ld' is an extra Node removed from 'this'). The |
| // combined optimization requires Identity only return direct inputs. |
| set_req(1, ld); |
| set_req(2, phase->intcon(0)); |
| return this; |
| } |
| else if( can_reshape && |
| ld->Opcode() == Op_LoadUS && |
| ld->outcnt() == 1 && ld->unique_out() == shl) |
| // Replace zero-extension-load with sign-extension-load |
| return new (phase->C) LoadSNode( ld->in(MemNode::Control), |
| ld->in(MemNode::Memory), |
| ld->in(MemNode::Address), |
| ld->adr_type(), TypeInt::SHORT, |
| MemNode::unordered); |
| } |
| |
| // Check for "(byte[i] <<24)>>24" which simply sign-extends |
| if( shift == 24 && |
| (t3 = phase->type(shl->in(2))->isa_int()) && |
| t3->is_con(24) ) { |
| Node *ld = shl->in(1); |
| if( ld->Opcode() == Op_LoadB ) { |
| // Sign extension is just useless here |
| set_req(1, ld); |
| set_req(2, phase->intcon(0)); |
| return this; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A RShiftINode shifts its input2 right by input1 amount. |
| const Type *RShiftINode::Value( PhaseTransform *phase ) const { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if (t1 == Type::BOTTOM || t2 == Type::BOTTOM) |
| return TypeInt::INT; |
| |
| if (t2 == TypeInt::INT) |
| return TypeInt::INT; |
| |
| const TypeInt *r1 = t1->is_int(); // Handy access |
| const TypeInt *r2 = t2->is_int(); // Handy access |
| |
| // If the shift is a constant, just shift the bounds of the type. |
| // For example, if the shift is 31, we just propagate sign bits. |
| if (r2->is_con()) { |
| uint shift = r2->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| // Shift by a multiple of 32 does nothing: |
| if (shift == 0) return t1; |
| // Calculate reasonably aggressive bounds for the result. |
| // This is necessary if we are to correctly type things |
| // like (x<<24>>24) == ((byte)x). |
| jint lo = (jint)r1->_lo >> (jint)shift; |
| jint hi = (jint)r1->_hi >> (jint)shift; |
| assert(lo <= hi, "must have valid bounds"); |
| const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen)); |
| #ifdef ASSERT |
| // Make sure we get the sign-capture idiom correct. |
| if (shift == BitsPerJavaInteger-1) { |
| if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>31 of + is 0"); |
| if (r1->_hi < 0) assert(ti == TypeInt::MINUS_1, ">>31 of - is -1"); |
| } |
| #endif |
| return ti; |
| } |
| |
| if( !r1->is_con() || !r2->is_con() ) |
| return TypeInt::INT; |
| |
| // Signed shift right |
| return TypeInt::make( r1->get_con() >> (r2->get_con()&31) ); |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *RShiftLNode::Identity( PhaseTransform *phase ) { |
| const TypeInt *ti = phase->type( in(2) )->isa_int(); // shift count is an int |
| return ( ti && ti->is_con() && ( ti->get_con() & ( BitsPerLong - 1 ) ) == 0 ) ? in(1) : this; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A RShiftLNode shifts its input2 right by input1 amount. |
| const Type *RShiftLNode::Value( PhaseTransform *phase ) const { |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if (t1 == Type::BOTTOM || t2 == Type::BOTTOM) |
| return TypeLong::LONG; |
| |
| if (t2 == TypeInt::INT) |
| return TypeLong::LONG; |
| |
| const TypeLong *r1 = t1->is_long(); // Handy access |
| const TypeInt *r2 = t2->is_int (); // Handy access |
| |
| // If the shift is a constant, just shift the bounds of the type. |
| // For example, if the shift is 63, we just propagate sign bits. |
| if (r2->is_con()) { |
| uint shift = r2->get_con(); |
| shift &= (2*BitsPerJavaInteger)-1; // semantics of Java shifts |
| // Shift by a multiple of 64 does nothing: |
| if (shift == 0) return t1; |
| // Calculate reasonably aggressive bounds for the result. |
| // This is necessary if we are to correctly type things |
| // like (x<<24>>24) == ((byte)x). |
| jlong lo = (jlong)r1->_lo >> (jlong)shift; |
| jlong hi = (jlong)r1->_hi >> (jlong)shift; |
| assert(lo <= hi, "must have valid bounds"); |
| const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen)); |
| #ifdef ASSERT |
| // Make sure we get the sign-capture idiom correct. |
| if (shift == (2*BitsPerJavaInteger)-1) { |
| if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>63 of + is 0"); |
| if (r1->_hi < 0) assert(tl == TypeLong::MINUS_1, ">>63 of - is -1"); |
| } |
| #endif |
| return tl; |
| } |
| |
| return TypeLong::LONG; // Give up |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *URShiftINode::Identity( PhaseTransform *phase ) { |
| const TypeInt *ti = phase->type( in(2) )->isa_int(); |
| if ( ti && ti->is_con() && ( ti->get_con() & ( BitsPerInt - 1 ) ) == 0 ) return in(1); |
| |
| // Check for "((x << LogBytesPerWord) + (wordSize-1)) >> LogBytesPerWord" which is just "x". |
| // Happens during new-array length computation. |
| // Safe if 'x' is in the range [0..(max_int>>LogBytesPerWord)] |
| Node *add = in(1); |
| if( add->Opcode() == Op_AddI ) { |
| const TypeInt *t2 = phase->type(add->in(2))->isa_int(); |
| if( t2 && t2->is_con(wordSize - 1) && |
| add->in(1)->Opcode() == Op_LShiftI ) { |
| // Check that shift_counts are LogBytesPerWord |
| Node *lshift_count = add->in(1)->in(2); |
| const TypeInt *t_lshift_count = phase->type(lshift_count)->isa_int(); |
| if( t_lshift_count && t_lshift_count->is_con(LogBytesPerWord) && |
| t_lshift_count == phase->type(in(2)) ) { |
| Node *x = add->in(1)->in(1); |
| const TypeInt *t_x = phase->type(x)->isa_int(); |
| if( t_x != NULL && 0 <= t_x->_lo && t_x->_hi <= (max_jint>>LogBytesPerWord) ) { |
| return x; |
| } |
| } |
| } |
| } |
| |
| return (phase->type(in(2))->higher_equal(TypeInt::ZERO)) ? in(1) : this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| Node *URShiftINode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| const TypeInt *t2 = phase->type( in(2) )->isa_int(); |
| if( !t2 || !t2->is_con() ) return NULL; // Right input is a constant |
| const int con = t2->get_con() & 31; // Shift count is always masked |
| if ( con == 0 ) return NULL; // let Identity() handle a 0 shift count |
| // We'll be wanting the right-shift amount as a mask of that many bits |
| const int mask = right_n_bits(BitsPerJavaInteger - con); |
| |
| int in1_op = in(1)->Opcode(); |
| |
| // Check for ((x>>>a)>>>b) and replace with (x>>>(a+b)) when a+b < 32 |
| if( in1_op == Op_URShiftI ) { |
| const TypeInt *t12 = phase->type( in(1)->in(2) )->isa_int(); |
| if( t12 && t12->is_con() ) { // Right input is a constant |
| assert( in(1) != in(1)->in(1), "dead loop in URShiftINode::Ideal" ); |
| const int con2 = t12->get_con() & 31; // Shift count is always masked |
| const int con3 = con+con2; |
| if( con3 < 32 ) // Only merge shifts if total is < 32 |
| return new (phase->C) URShiftINode( in(1)->in(1), phase->intcon(con3) ); |
| } |
| } |
| |
| // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z |
| // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z". |
| // If Q is "X << z" the rounding is useless. Look for patterns like |
| // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask. |
| Node *add = in(1); |
| if( in1_op == Op_AddI ) { |
| Node *lshl = add->in(1); |
| if( lshl->Opcode() == Op_LShiftI && |
| phase->type(lshl->in(2)) == t2 ) { |
| Node *y_z = phase->transform( new (phase->C) URShiftINode(add->in(2),in(2)) ); |
| Node *sum = phase->transform( new (phase->C) AddINode( lshl->in(1), y_z ) ); |
| return new (phase->C) AndINode( sum, phase->intcon(mask) ); |
| } |
| } |
| |
| // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z) |
| // This shortens the mask. Also, if we are extracting a high byte and |
| // storing it to a buffer, the mask will be removed completely. |
| Node *andi = in(1); |
| if( in1_op == Op_AndI ) { |
| const TypeInt *t3 = phase->type( andi->in(2) )->isa_int(); |
| if( t3 && t3->is_con() ) { // Right input is a constant |
| jint mask2 = t3->get_con(); |
| mask2 >>= con; // *signed* shift downward (high-order zeroes do not help) |
| Node *newshr = phase->transform( new (phase->C) URShiftINode(andi->in(1), in(2)) ); |
| return new (phase->C) AndINode(newshr, phase->intcon(mask2)); |
| // The negative values are easier to materialize than positive ones. |
| // A typical case from address arithmetic is ((x & ~15) >> 4). |
| // It's better to change that to ((x >> 4) & ~0) versus |
| // ((x >> 4) & 0x0FFFFFFF). The difference is greatest in LP64. |
| } |
| } |
| |
| // Check for "(X << z ) >>> z" which simply zero-extends |
| Node *shl = in(1); |
| if( in1_op == Op_LShiftI && |
| phase->type(shl->in(2)) == t2 ) |
| return new (phase->C) AndINode( shl->in(1), phase->intcon(mask) ); |
| |
| return NULL; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A URShiftINode shifts its input2 right by input1 amount. |
| const Type *URShiftINode::Value( PhaseTransform *phase ) const { |
| // (This is a near clone of RShiftINode::Value.) |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeInt::ZERO ) return TypeInt::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if (t1 == Type::BOTTOM || t2 == Type::BOTTOM) |
| return TypeInt::INT; |
| |
| if (t2 == TypeInt::INT) |
| return TypeInt::INT; |
| |
| const TypeInt *r1 = t1->is_int(); // Handy access |
| const TypeInt *r2 = t2->is_int(); // Handy access |
| |
| if (r2->is_con()) { |
| uint shift = r2->get_con(); |
| shift &= BitsPerJavaInteger-1; // semantics of Java shifts |
| // Shift by a multiple of 32 does nothing: |
| if (shift == 0) return t1; |
| // Calculate reasonably aggressive bounds for the result. |
| jint lo = (juint)r1->_lo >> (juint)shift; |
| jint hi = (juint)r1->_hi >> (juint)shift; |
| if (r1->_hi >= 0 && r1->_lo < 0) { |
| // If the type has both negative and positive values, |
| // there are two separate sub-domains to worry about: |
| // The positive half and the negative half. |
| jint neg_lo = lo; |
| jint neg_hi = (juint)-1 >> (juint)shift; |
| jint pos_lo = (juint) 0 >> (juint)shift; |
| jint pos_hi = hi; |
| lo = MIN2(neg_lo, pos_lo); // == 0 |
| hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift; |
| } |
| assert(lo <= hi, "must have valid bounds"); |
| const TypeInt* ti = TypeInt::make(lo, hi, MAX2(r1->_widen,r2->_widen)); |
| #ifdef ASSERT |
| // Make sure we get the sign-capture idiom correct. |
| if (shift == BitsPerJavaInteger-1) { |
| if (r1->_lo >= 0) assert(ti == TypeInt::ZERO, ">>>31 of + is 0"); |
| if (r1->_hi < 0) assert(ti == TypeInt::ONE, ">>>31 of - is +1"); |
| } |
| #endif |
| return ti; |
| } |
| |
| // |
| // Do not support shifted oops in info for GC |
| // |
| // else if( t1->base() == Type::InstPtr ) { |
| // |
| // const TypeInstPtr *o = t1->is_instptr(); |
| // if( t1->singleton() ) |
| // return TypeInt::make( ((uint32)o->const_oop() + o->_offset) >> shift ); |
| // } |
| // else if( t1->base() == Type::KlassPtr ) { |
| // const TypeKlassPtr *o = t1->is_klassptr(); |
| // if( t1->singleton() ) |
| // return TypeInt::make( ((uint32)o->const_oop() + o->_offset) >> shift ); |
| // } |
| |
| return TypeInt::INT; |
| } |
| |
| //============================================================================= |
| //------------------------------Identity--------------------------------------- |
| Node *URShiftLNode::Identity( PhaseTransform *phase ) { |
| const TypeInt *ti = phase->type( in(2) )->isa_int(); // shift count is an int |
| return ( ti && ti->is_con() && ( ti->get_con() & ( BitsPerLong - 1 ) ) == 0 ) ? in(1) : this; |
| } |
| |
| //------------------------------Ideal------------------------------------------ |
| Node *URShiftLNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
| const TypeInt *t2 = phase->type( in(2) )->isa_int(); |
| if( !t2 || !t2->is_con() ) return NULL; // Right input is a constant |
| const int con = t2->get_con() & ( BitsPerLong - 1 ); // Shift count is always masked |
| if ( con == 0 ) return NULL; // let Identity() handle a 0 shift count |
| // note: mask computation below does not work for 0 shift count |
| // We'll be wanting the right-shift amount as a mask of that many bits |
| const jlong mask = (((jlong)CONST64(1) << (jlong)(BitsPerJavaLong - con)) -1); |
| |
| // Check for ((x << z) + Y) >>> z. Replace with x + con>>>z |
| // The idiom for rounding to a power of 2 is "(Q+(2^z-1)) >>> z". |
| // If Q is "X << z" the rounding is useless. Look for patterns like |
| // ((X<<Z) + Y) >>> Z and replace with (X + Y>>>Z) & Z-mask. |
| Node *add = in(1); |
| if( add->Opcode() == Op_AddL ) { |
| Node *lshl = add->in(1); |
| if( lshl->Opcode() == Op_LShiftL && |
| phase->type(lshl->in(2)) == t2 ) { |
| Node *y_z = phase->transform( new (phase->C) URShiftLNode(add->in(2),in(2)) ); |
| Node *sum = phase->transform( new (phase->C) AddLNode( lshl->in(1), y_z ) ); |
| return new (phase->C) AndLNode( sum, phase->longcon(mask) ); |
| } |
| } |
| |
| // Check for (x & mask) >>> z. Replace with (x >>> z) & (mask >>> z) |
| // This shortens the mask. Also, if we are extracting a high byte and |
| // storing it to a buffer, the mask will be removed completely. |
| Node *andi = in(1); |
| if( andi->Opcode() == Op_AndL ) { |
| const TypeLong *t3 = phase->type( andi->in(2) )->isa_long(); |
| if( t3 && t3->is_con() ) { // Right input is a constant |
| jlong mask2 = t3->get_con(); |
| mask2 >>= con; // *signed* shift downward (high-order zeroes do not help) |
| Node *newshr = phase->transform( new (phase->C) URShiftLNode(andi->in(1), in(2)) ); |
| return new (phase->C) AndLNode(newshr, phase->longcon(mask2)); |
| } |
| } |
| |
| // Check for "(X << z ) >>> z" which simply zero-extends |
| Node *shl = in(1); |
| if( shl->Opcode() == Op_LShiftL && |
| phase->type(shl->in(2)) == t2 ) |
| return new (phase->C) AndLNode( shl->in(1), phase->longcon(mask) ); |
| |
| return NULL; |
| } |
| |
| //------------------------------Value------------------------------------------ |
| // A URShiftINode shifts its input2 right by input1 amount. |
| const Type *URShiftLNode::Value( PhaseTransform *phase ) const { |
| // (This is a near clone of RShiftLNode::Value.) |
| const Type *t1 = phase->type( in(1) ); |
| const Type *t2 = phase->type( in(2) ); |
| // Either input is TOP ==> the result is TOP |
| if( t1 == Type::TOP ) return Type::TOP; |
| if( t2 == Type::TOP ) return Type::TOP; |
| |
| // Left input is ZERO ==> the result is ZERO. |
| if( t1 == TypeLong::ZERO ) return TypeLong::ZERO; |
| // Shift by zero does nothing |
| if( t2 == TypeInt::ZERO ) return t1; |
| |
| // Either input is BOTTOM ==> the result is BOTTOM |
| if (t1 == Type::BOTTOM || t2 == Type::BOTTOM) |
| return TypeLong::LONG; |
| |
| if (t2 == TypeInt::INT) |
| return TypeLong::LONG; |
| |
| const TypeLong *r1 = t1->is_long(); // Handy access |
| const TypeInt *r2 = t2->is_int (); // Handy access |
| |
| if (r2->is_con()) { |
| uint shift = r2->get_con(); |
| shift &= BitsPerJavaLong - 1; // semantics of Java shifts |
| // Shift by a multiple of 64 does nothing: |
| if (shift == 0) return t1; |
| // Calculate reasonably aggressive bounds for the result. |
| jlong lo = (julong)r1->_lo >> (juint)shift; |
| jlong hi = (julong)r1->_hi >> (juint)shift; |
| if (r1->_hi >= 0 && r1->_lo < 0) { |
| // If the type has both negative and positive values, |
| // there are two separate sub-domains to worry about: |
| // The positive half and the negative half. |
| jlong neg_lo = lo; |
| jlong neg_hi = (julong)-1 >> (juint)shift; |
| jlong pos_lo = (julong) 0 >> (juint)shift; |
| jlong pos_hi = hi; |
| //lo = MIN2(neg_lo, pos_lo); // == 0 |
| lo = neg_lo < pos_lo ? neg_lo : pos_lo; |
| //hi = MAX2(neg_hi, pos_hi); // == -1 >>> shift; |
| hi = neg_hi > pos_hi ? neg_hi : pos_hi; |
| } |
| assert(lo <= hi, "must have valid bounds"); |
| const TypeLong* tl = TypeLong::make(lo, hi, MAX2(r1->_widen,r2->_widen)); |
| #ifdef ASSERT |
| // Make sure we get the sign-capture idiom correct. |
| if (shift == BitsPerJavaLong - 1) { |
| if (r1->_lo >= 0) assert(tl == TypeLong::ZERO, ">>>63 of + is 0"); |
| if (r1->_hi < 0) assert(tl == TypeLong::ONE, ">>>63 of - is +1"); |
| } |
| #endif |
| return tl; |
| } |
| |
| return TypeLong::LONG; // Give up |
| } |
