view src/share/vm/opto/mathexactnode.cpp @ 17716:cdb71841f4bc

6498581: ThreadInterruptTest3 produces wrong output on Windows Summary: There is race condition between os::interrupt and os::is_interrupted on Windows. In JVM_Sleep(Thread.sleep), check if thread gets interrupted, it may see interrupted but not really interrupted so cause spurious waking up (early return from sleep). Fix by checking if interrupt event really gets set thus prevent false return. For intrinsic of _isInterrupted, on Windows, go fastpath only on bit not set. Reviewed-by: acorn, kvn Contributed-by: david.holmes@oracle.com, yumin.qi@oracle.com
author minqi
date Wed, 26 Feb 2014 15:20:41 -0800
parents 59e8ad757e19
children cd5d10655495
line wrap: on
line source

/*
 * Copyright (c) 2013, 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/cfgnode.hpp"
#include "opto/machnode.hpp"
#include "opto/matcher.hpp"
#include "opto/mathexactnode.hpp"
#include "opto/subnode.hpp"

MathExactNode::MathExactNode(Node* ctrl, Node* in1) : MultiNode(2) {
  init_class_id(Class_MathExact);
  init_req(0, ctrl);
  init_req(1, in1);
}

MathExactNode::MathExactNode(Node* ctrl, Node* in1, Node* in2) : MultiNode(3) {
  init_class_id(Class_MathExact);
  init_req(0, ctrl);
  init_req(1, in1);
  init_req(2, in2);
}

BoolNode* MathExactNode::bool_node() const {
  Node* flags = flags_node();
  BoolNode* boolnode = flags->unique_out()->as_Bool();
  assert(boolnode != NULL, "must have BoolNode");
  return boolnode;
}

IfNode* MathExactNode::if_node() const {
  BoolNode* boolnode = bool_node();
  IfNode* ifnode = boolnode->unique_out()->as_If();
  assert(ifnode != NULL, "must have IfNode");
  return ifnode;
}

Node* MathExactNode::control_node() const {
  IfNode* ifnode = if_node();
  return ifnode->in(0);
}

Node* MathExactNode::non_throwing_branch() const {
  IfNode* ifnode = if_node();
  if (bool_node()->_test._test == BoolTest::overflow) {
    return ifnode->proj_out(0);
  }
  return ifnode->proj_out(1);
}

// If the MathExactNode won't overflow we have to replace the
// FlagsProjNode and ProjNode that is generated by the MathExactNode
Node* MathExactNode::no_overflow(PhaseGVN* phase, Node* new_result) {
  PhaseIterGVN* igvn = phase->is_IterGVN();
  if (igvn) {
    ProjNode* result = result_node();
    ProjNode* flags = flags_node();

    if (result != NULL) {
      igvn->replace_node(result, new_result);
    }

    if (flags != NULL) {
      BoolNode* boolnode = bool_node();
      switch (boolnode->_test._test) {
        case BoolTest::overflow:
          // if the check is for overflow - never taken
          igvn->replace_node(boolnode, phase->intcon(0));
          break;
        case BoolTest::no_overflow:
          // if the check is for no overflow - always taken
          igvn->replace_node(boolnode, phase->intcon(1));
          break;
        default:
          fatal("Unexpected value of BoolTest");
          break;
      }
      flags->del_req(0);
    }
  }
  return new_result;
}

Node* MathExactINode::match(const ProjNode* proj, const Matcher* m) {
  uint ideal_reg = proj->ideal_reg();
  RegMask rm;
  if (proj->_con == result_proj_node) {
    rm = m->mathExactI_result_proj_mask();
  } else {
    assert(proj->_con == flags_proj_node, "must be result or flags");
    assert(ideal_reg == Op_RegFlags, "sanity");
    rm = m->mathExactI_flags_proj_mask();
  }
  return new (m->C) MachProjNode(this, proj->_con, rm, ideal_reg);
}

Node* MathExactLNode::match(const ProjNode* proj, const Matcher* m) {
  uint ideal_reg = proj->ideal_reg();
  RegMask rm;
  if (proj->_con == result_proj_node) {
    rm = m->mathExactL_result_proj_mask();
  } else {
    assert(proj->_con == flags_proj_node, "must be result or flags");
    assert(ideal_reg == Op_RegFlags, "sanity");
    rm = m->mathExactI_flags_proj_mask();
  }
  return new (m->C) MachProjNode(this, proj->_con, rm, ideal_reg);
}

Node* AddExactINode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jint val1 = arg1->get_int();
    jint val2 = arg2->get_int();
    jint result = val1 + val2;
    // Hacker's Delight 2-12 Overflow if both arguments have the opposite sign of the result
    if ( (((val1 ^ result) & (val2 ^ result)) >= 0)) {
      Node* con_result = ConINode::make(phase->C, result);
      return no_overflow(phase, con_result);
    }
    return NULL;
  }

  if (type1 == TypeInt::ZERO || type2 == TypeInt::ZERO) { // (Add 0 x) == x
    Node* add_result = new (phase->C) AddINode(arg1, arg2);
    return no_overflow(phase, add_result);
  }

  if (type2->singleton()) {
    return NULL; // no change - keep constant on the right
  }

  if (type1->singleton()) {
    // Make it x + Constant - move constant to the right
    swap_edges(1, 2);
    return this;
  }

  if (arg2->is_Load()) {
    return NULL; // no change - keep load on the right
  }

  if (arg1->is_Load()) {
    // Make it x + Load - move load to the right
    swap_edges(1, 2);
    return this;
  }

  if (arg1->_idx > arg2->_idx) {
    // Sort the edges
    swap_edges(1, 2);
    return this;
  }

  return NULL;
}

Node* AddExactLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jlong val1 = arg1->get_long();
    jlong val2 = arg2->get_long();
    jlong result = val1 + val2;
    // Hacker's Delight 2-12 Overflow if both arguments have the opposite sign of the result
    if ( (((val1 ^ result) & (val2 ^ result)) >= 0)) {
      Node* con_result = ConLNode::make(phase->C, result);
      return no_overflow(phase, con_result);
    }
    return NULL;
  }

  if (type1 == TypeLong::ZERO || type2 == TypeLong::ZERO) { // (Add 0 x) == x
    Node* add_result = new (phase->C) AddLNode(arg1, arg2);
    return no_overflow(phase, add_result);
  }

  if (type2->singleton()) {
    return NULL; // no change - keep constant on the right
  }

  if (type1->singleton()) {
    // Make it x + Constant - move constant to the right
    swap_edges(1, 2);
    return this;
  }

  if (arg2->is_Load()) {
    return NULL; // no change - keep load on the right
  }

  if (arg1->is_Load()) {
    // Make it x + Load - move load to the right
    swap_edges(1, 2);
    return this;
  }

  if (arg1->_idx > arg2->_idx) {
    // Sort the edges
    swap_edges(1, 2);
    return this;
  }

  return NULL;
}

Node* SubExactINode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jint val1 = arg1->get_int();
    jint val2 = arg2->get_int();
    jint result = val1 - val2;

    // Hacker's Delight 2-12 Overflow iff the arguments have different signs and
    // the sign of the result is different than the sign of arg1
    if (((val1 ^ val2) & (val1 ^ result)) >= 0) {
      Node* con_result = ConINode::make(phase->C, result);
      return no_overflow(phase, con_result);
    }
    return NULL;
  }

  if (type1 == TypeInt::ZERO || type2 == TypeInt::ZERO) {
    // Sub with zero is the same as add with zero
    Node* add_result = new (phase->C) AddINode(arg1, arg2);
    return no_overflow(phase, add_result);
  }

  return NULL;
}

Node* SubExactLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jlong val1 = arg1->get_long();
    jlong val2 = arg2->get_long();
    jlong result = val1 - val2;

    // Hacker's Delight 2-12 Overflow iff the arguments have different signs and
    // the sign of the result is different than the sign of arg1
    if (((val1 ^ val2) & (val1 ^ result)) >= 0) {
      Node* con_result = ConLNode::make(phase->C, result);
      return no_overflow(phase, con_result);
    }
    return NULL;
  }

  if (type1 == TypeLong::ZERO || type2 == TypeLong::ZERO) {
    // Sub with zero is the same as add with zero
    Node* add_result = new (phase->C) AddLNode(arg1, arg2);
    return no_overflow(phase, add_result);
  }

  return NULL;
}

Node* NegExactINode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node *arg = in(1);

  const Type* type = phase->type(arg);
  if (type != Type::TOP && type->singleton()) {
    jint value = arg->get_int();
    if (value != min_jint) {
      Node* neg_result = ConINode::make(phase->C, -value);
      return no_overflow(phase, neg_result);
    }
  }
  return NULL;
}

Node* NegExactLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node *arg = in(1);

  const Type* type = phase->type(arg);
  if (type != Type::TOP && type->singleton()) {
    jlong value = arg->get_long();
    if (value != min_jlong) {
      Node* neg_result = ConLNode::make(phase->C, -value);
      return no_overflow(phase, neg_result);
    }
  }
  return NULL;
}

Node* MulExactINode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jint val1 = arg1->get_int();
    jint val2 = arg2->get_int();
    jlong result = (jlong) val1 * (jlong) val2;
    if ((jint) result == result) {
      // no overflow
      Node* mul_result = ConINode::make(phase->C, result);
      return no_overflow(phase, mul_result);
    }
  }

  if (type1 == TypeInt::ZERO || type2 == TypeInt::ZERO) {
    return no_overflow(phase, ConINode::make(phase->C, 0));
  }

  if (type1 == TypeInt::ONE) {
    Node* mul_result = new (phase->C) AddINode(arg2, phase->intcon(0));
    return no_overflow(phase, mul_result);
  }
  if (type2 == TypeInt::ONE) {
    Node* mul_result = new (phase->C) AddINode(arg1, phase->intcon(0));
    return no_overflow(phase, mul_result);
  }

  if (type1 == TypeInt::MINUS_1) {
    return new (phase->C) NegExactINode(NULL, arg2);
  }

  if (type2 == TypeInt::MINUS_1) {
    return new (phase->C) NegExactINode(NULL, arg1);
  }

  return NULL;
}

Node* MulExactLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
  Node* arg1 = in(1);
  Node* arg2 = in(2);

  const Type* type1 = phase->type(arg1);
  const Type* type2 = phase->type(arg2);

  if (type1 != Type::TOP && type1->singleton() &&
      type2 != Type::TOP && type2->singleton()) {
    jlong val1 = arg1->get_long();
    jlong val2 = arg2->get_long();

    jlong result = val1 * val2;
    jlong ax = (val1 < 0 ? -val1 : val1);
    jlong ay = (val2 < 0 ? -val2 : val2);

    bool overflow = false;
    if ((ax | ay) & CONST64(0xFFFFFFFF00000000)) {
      // potential overflow if any bit in upper 32 bits are set
      if ((val1 == min_jlong && val2 == -1) || (val2 == min_jlong && val1 == -1)) {
        // -1 * Long.MIN_VALUE will overflow
        overflow = true;
      } else if (val2 != 0 && (result / val2 != val1)) {
        overflow = true;
      }
    }

    if (!overflow) {
      Node* mul_result = ConLNode::make(phase->C, result);
      return no_overflow(phase, mul_result);
    }
  }

  if (type1 == TypeLong::ZERO || type2 == TypeLong::ZERO) {
    return no_overflow(phase, ConLNode::make(phase->C, 0));
  }

  if (type1 == TypeLong::ONE) {
    Node* mul_result = new (phase->C) AddLNode(arg2, phase->longcon(0));
    return no_overflow(phase, mul_result);
  }
  if (type2 == TypeLong::ONE) {
    Node* mul_result = new (phase->C) AddLNode(arg1, phase->longcon(0));
    return no_overflow(phase, mul_result);
  }

  if (type1 == TypeLong::MINUS_1) {
    return new (phase->C) NegExactLNode(NULL, arg2);
  }

  if (type2 == TypeLong::MINUS_1) {
    return new (phase->C) NegExactLNode(NULL, arg1);
  }

  return NULL;
}