Revision: 13464
Author: [email protected]
Date: Tue Jan 22 05:55:22 2013
Log: Fix pattern detection for replacing shifts by rotation.
BUG=2499
[email protected]
Review URL: https://chromiumcodereview.appspot.com/12047015
Patch from Hirofumi Mako <[email protected]>.
http://code.google.com/p/v8/source/detail?r=13464
Added:
/branches/bleeding_edge/test/mjsunit/regress/regress-2499.js
Modified:
/branches/bleeding_edge/src/hydrogen.cc
=======================================
--- /dev/null
+++ /branches/bleeding_edge/test/mjsunit/regress/regress-2499.js Tue Jan 22
05:55:22 2013
@@ -0,0 +1,40 @@
+// Copyright 2013 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.
+
+// Flags: --allow-natives-syntax
+
+function foo(word, nBits) {
+ return (word[1] >>> nBits) | (word[0] << (32 - nBits));
+}
+
+word = [0x1001, 0];
+
+var expected = foo(word, 1);
+foo(word, 1);
+%OptimizeFunctionOnNextCall(foo);
+var optimized = foo(word, 1);
+assertEquals(expected, optimized)
=======================================
--- /branches/bleeding_edge/src/hydrogen.cc Tue Jan 22 04:03:35 2013
+++ /branches/bleeding_edge/src/hydrogen.cc Tue Jan 22 05:55:22 2013
@@ -8464,6 +8464,7 @@
HValue* const32_minus_sa) {
if (!const32_minus_sa->IsSub()) return false;
HSub* sub = HSub::cast(const32_minus_sa);
+ if (sa != sub->right()) return false;
HValue* const32 = sub->left();
if (!const32->IsConstant() ||
HConstant::cast(const32)->Integer32Value() != 32) {
@@ -8492,6 +8493,7 @@
} else {
return false;
}
+ if (shl->left() != shr->left()) return false;
if (!ShiftAmountsAllowReplaceByRotate(shl->right(), shr->right()) &&
!ShiftAmountsAllowReplaceByRotate(shr->right(), shl->right())) {
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
