From f3da5ff626dbd20b54a3f293df55f18a64475593 Mon Sep 17 00:00:00 2001 From: "iposva@chromium.org" Date: Wed, 7 Jan 2009 23:26:31 +0000 Subject: [PATCH] Fix for issue 171: - Make sure to not destroy the instance type by slightly rearranging the code. - Added regression test. Review URL: http://codereview.chromium.org/16594 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1042 ce2b1a6d-e550-0410-aec6-3dcde31c8c00 --- src/stub-cache-arm.cc | 16 ++++++++------- test/mjsunit/regress/regress-171.js | 41 +++++++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+), 7 deletions(-) create mode 100644 test/mjsunit/regress/regress-171.js diff --git a/src/stub-cache-arm.cc b/src/stub-cache-arm.cc index 3584a4e..4470822 100644 --- a/src/stub-cache-arm.cc +++ b/src/stub-cache-arm.cc @@ -312,20 +312,24 @@ static void GenerateStringCheck(MacroAssembler* masm, } +// Generate code to load the length from a string object and return the length. +// If the receiver object is not a string or a wrapped string object the +// execution continues at the miss label. The register containing the +// receiver is potentially clobbered. void StubCompiler::GenerateLoadStringLength2(MacroAssembler* masm, Register receiver, Register scratch1, Register scratch2, Label* miss) { - Label load_length, check_wrapper; + Label check_string, check_wrapper; + __ bind(&check_string); // Check if the object is a string leaving the instance type in the // scratch1 register. GenerateStringCheck(masm, receiver, scratch1, scratch2, miss, &check_wrapper); // Load length directly from the string. - __ bind(&load_length); __ and_(scratch1, scratch1, Operand(kStringSizeMask)); __ add(scratch1, scratch1, Operand(String::kHashShift)); __ ldr(r0, FieldMemOperand(receiver, String::kLengthOffset)); @@ -338,11 +342,9 @@ void StubCompiler::GenerateLoadStringLength2(MacroAssembler* masm, __ cmp(scratch1, Operand(JS_VALUE_TYPE)); __ b(ne, miss); - // Check if the wrapped value is a string and load the length - // directly if it is. - __ ldr(r0, FieldMemOperand(receiver, JSValue::kValueOffset)); - GenerateStringCheck(masm, receiver, scratch1, scratch1, miss, miss); - __ b(&load_length); + // Unwrap the value in place and check if the wrapped value is a string. + __ ldr(receiver, FieldMemOperand(receiver, JSValue::kValueOffset)); + __ b(&check_string); } diff --git a/test/mjsunit/regress/regress-171.js b/test/mjsunit/regress/regress-171.js new file mode 100644 index 0000000..fe981da --- /dev/null +++ b/test/mjsunit/regress/regress-171.js @@ -0,0 +1,41 @@ +// Copyright 2009 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 f(s) { return s.length; } +function g(s, key) { return s[key]; } + +assertEquals(f(new String("a")), 1); +assertEquals(f(new String("a")), 1); +assertEquals(f(new String("a")), 1); +assertEquals(f("a"), 1); +assertEquals(f(new String("a")), 1); + +assertEquals(g(new String("a"), "length"), 1); +assertEquals(g(new String("a"), "length"), 1); +assertEquals(g(new String("a"), "length"), 1); +assertEquals(g("a", "length"), 1); +assertEquals(g(new String("a"), "length"), 1); -- 2.7.4