Reviewers: fschneider, Description: Add check for overflow after MUL operations in side-effect free int32 expressions.
BUG=http://code.google.com/p/v8/issues/detail?id=927 TEST=test/mjsunit/regress/regress-927.js Please review this at http://codereview.chromium.org/4746001/show SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/ Affected files: M src/ia32/codegen-ia32.cc A test/mjsunit/regress/regress-927.js Index: src/ia32/codegen-ia32.cc =================================================================== --- src/ia32/codegen-ia32.cc (revision 5792) +++ src/ia32/codegen-ia32.cc (working copy) @@ -8578,9 +8578,11 @@ } right.Unuse(); frame_->Push(&left); - if (!node->to_int32()) { - // If ToInt32 is called on the result of ADD, SUB, or MUL, we don't + if (!node->to_int32() || op == Token::MUL) { + // If ToInt32 is called on the result of ADD, SUB, we don't // care about overflows. + // Result of MUL can be non-representable precisely in double so + // we have to check for overflow. unsafe_bailout_->Branch(overflow); } break; Index: test/mjsunit/regress/regress-927.js =================================================================== --- test/mjsunit/regress/regress-927.js (revision 0) +++ test/mjsunit/regress/regress-927.js (revision 0) @@ -0,0 +1,33 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +function a1() { + var a2 = -1756315459; + return ((((a2 & a2) ^ 1) * a2) << -10); +} + +assertEquals(a1(), -2147483648); -- v8-dev mailing list [email protected] http://groups.google.com/group/v8-dev
