From 1d6710c933448671ae060351c547cff4c71498c0 Mon Sep 17 00:00:00 2001 From: "titzer@chromium.org" Date: Tue, 3 Dec 2013 18:04:45 +0000 Subject: [PATCH] Add some test cases with dead loops. BUG= R=verwaest@chromium.org Review URL: https://codereview.chromium.org/98323004 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18242 ce2b1a6d-e550-0410-aec6-3dcde31c8c00 --- test/mjsunit/compiler/dead-loops-neg.js | 100 ++++++++++++++++++++++++++++++++ test/mjsunit/compiler/dead-loops.js | 87 +++++++++++++++++++++++++++ 2 files changed, 187 insertions(+) create mode 100644 test/mjsunit/compiler/dead-loops-neg.js create mode 100644 test/mjsunit/compiler/dead-loops.js diff --git a/test/mjsunit/compiler/dead-loops-neg.js b/test/mjsunit/compiler/dead-loops-neg.js new file mode 100644 index 0000000..dbf500b --- /dev/null +++ b/test/mjsunit/compiler/dead-loops-neg.js @@ -0,0 +1,100 @@ +// 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 + +// Presents negative opportunities for dead loop removal. + +function loop1() { + while (true) return; +} + +function loop2() { + var i = 0; + while (i++ < 10) ; + return i; // value of {i} escapes. + // can only remove the loop with induction variable analysis. +} + +function loop3() { + var i = 0; + for (; i < 10; i++) ; + return i; // value of {i} escapes. + // can only remove the loop with induction variable analysis. +} + +function loop4() { + var a = 0; + for (var i = 0; i < 10; i++) a++; + return a; // value of {a} escapes. + // can only remove the loop with induction variable analysis. +} + +function loop5() { + var a = new Int32Array(4), sum = 0; + for (var i = 0; i < a.length; i++) { + sum += a[i]; + } + return sum; // {sum} escapes. + // can only remove the loop by figuring out that all elements of {a} are 0. +} + +function loop6(a) { + for (var i = 0; i < a; i++) ; // implicit a.valueOf(). + // can only remove the loop by guarding on the type of a. +} + +function loop7(a) { + for (var i = 0; i < 10; i++) a.toString(); // unknown side-effect on a. + // can only remove the loop by guarding on the type of a. +} + +function loop8(a) { + for (var i = 0; i < 10; i++) a.valueOf(); // unknown side-effect on a. + // can only remove the loop by guarding on the type of a. +} + +var no_params_loops = [loop1, loop2, loop3, loop4, loop5, loop6]; +var params_loops = [loop6, loop7, loop8]; + +for (var i = 0; i < no_params_loops.length; i++) { + var f = no_params_loops[i]; + f(); + f(); + f(); + %OptimizeFunctionOnNextCall(f); + f(); +} + +for (var i = 0; i < params_loops.length; i++) { + var f = params_loops[i]; + f(3); + f(7); + f(11); + %OptimizeFunctionOnNextCall(f); + f(9); +} diff --git a/test/mjsunit/compiler/dead-loops.js b/test/mjsunit/compiler/dead-loops.js new file mode 100644 index 0000000..2301b12 --- /dev/null +++ b/test/mjsunit/compiler/dead-loops.js @@ -0,0 +1,87 @@ +// 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 + +// Presents opportunities for dead loop removal. + +function loop1() { + while (false) ; // doesn't even loop. +} + +function loop2() { + var i = 0; + while (i++ < 10) ; // nothing in the body. +} + +function loop3() { + for (var i = 0; i < 10; i++) ; // nothing in the body. +} + +function loop4() { + var a = 0; + for (var i = 0; i < 10; i++) a++; // {a} is dead after the loop. +} + +function loop5() { + var a = new Int32Array(4), sum = 0; + for (var i = 0; i < a.length; i++) { + // Involves only reads on typed arrays, and {i} doesn't overflow. + sum += a[i]; + } +} + +function loop6() { + var a = new Array(4), sum = 0; + for (var i = 0; i < a.length; i++) { + // Involves only in-bounds read on the array {a}. + // Have to prove that {a} doesn't have getters...? + sum += a[i]; + } +} + +function loop7() { + for (var i = 0; i < 10; i++) { + new Object(); // Have to prove the allocation doesn't escape. + } +} + +function loop8() { + for (var i = 0; i < 10; i++) { + var x = {}; // Have to prove the allocation doesn't escape. + } +} + +var loops = [loop1, loop2, loop3, loop4, loop5, loop6, loop7, loop8]; + +for (var i = 0; i < loops.length; i++) { + var f = loops[i]; + f(); + f(); + %OptimizeFunctionOnNextCall(f); + f(); +} -- 2.7.4