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Edit File: debug-liveedit-patch-positions.js
// 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. // Flags: --expose-debug-as debug // Get the Debug object exposed from the debug context global object. // Scenario: some function is being edited; the outer function has to have its // positions patched. Accoring to a special markup of function text // corresponding byte-code PCs should coincide before change and after it. Debug = debug.Debug eval( "function F1() { return 5; }\n" + "function ChooseAnimal(/*$*/ ) {\n" + "/*$*/ var x = F1(/*$*/ );\n" + "/*$*/ var res/*$*/ =/*$*/ (function() { return 'Cat'; } )();\n" + "/*$*/ var y/*$*/ = F2(/*$*/ F1()/*$*/ , F1(/*$*/ )/*$*/ );\n" + "/*$*/ if (/*$*/ x.toString(/*$*/ )) { /*$*/ y = 3;/*$*/ } else {/*$*/ y = 8;/*$*/ }\n" + "/*$*/ var z = /*$*/ x * y;\n" + "/*$*/ return/*$*/ res/*$*/ + z;/*$*/ }\n" + "function F2(x, y) { return x + y; }" ); // Find all *$* markers in text of the function and read corresponding statement // PCs. function ReadMarkerPositions(func) { var text = func.toString(); var positions = new Array(); var match; var pattern = /\/\*\$\*\//g; while ((match = pattern.exec(text)) != null) { positions.push(match.index); } return positions; } function ReadPCMap(func, positions) { var res = new Array(); for (var i = 0; i < positions.length; i++) { var pc = Debug.LiveEdit.GetPcFromSourcePos(func, positions[i]); if (typeof pc === 'undefined') { // Function was marked for recompilation and it's code was replaced with a // stub. This can happen at any time especially if we are running with // --stress-opt. There is no way to get PCs now. return; } res.push(pc); } return res; } function ApplyPatch(orig_animal, new_animal) { var res = ChooseAnimal(); assertEquals(orig_animal + "15", res); var script = Debug.findScript(ChooseAnimal); var orig_string = "'" + orig_animal + "'"; var patch_string = "'" + new_animal + "'"; var patch_pos = script.source.indexOf(orig_string); var change_log = new Array(); Debug.LiveEdit.TestApi.ApplySingleChunkPatch(script, patch_pos, orig_string.length, patch_string, change_log); print("Change log: " + JSON.stringify(change_log) + "\n"); var markerPositions = ReadMarkerPositions(ChooseAnimal); var pcArray = ReadPCMap(ChooseAnimal, markerPositions); var res = ChooseAnimal(); assertEquals(new_animal + "15", res); return pcArray; } var pcArray1 = ApplyPatch('Cat', 'Dog'); // When we patched function for the first time it was deoptimized. // Check that after the second patch maping between sources position and // pcs will not change. var pcArray2 = ApplyPatch('Dog', 'Capybara'); print(pcArray1); print(pcArray2); // Function can be marked for recompilation at any point (especially if we are // running with --stress-opt). When we mark function for recompilation we // replace it's code with stub. So there is no reliable way to get PCs for // function. if (pcArray1 && pcArray2) { assertArrayEquals(pcArray1, pcArray2); }