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Remove the last of the obsolete *-delay.js files. This one

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is replaced by src/liveedit-debugger.js.
Review URL: http://codereview.chromium.org/1158005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4221 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
kasperl@chromium.org 2010-03-23 12:36:41 +00:00
parent 9240342ad6
commit 9dfb673fab
1 changed files with 0 additions and 431 deletions
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src/liveedit-delay.js
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// 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.
// LiveEdit feature implementation. The script should be executed after
// debug-delay.js.
// Changes script text and recompiles all relevant functions if possible.
// The change is always a substring (change_pos, change_pos + change_len)
// being replaced with a completely different string new_str.
//
// Only one function will have its Code changed in result of this function.
// All nested functions (should they have any instances at the moment) are left
// unchanged and re-linked to a newly created script instance representing old
// version of the source. (Generally speaking,
// during the change all nested functions are erased and completely different
// set of nested functions are introduced.) All other functions just have
// their positions updated.
//
// @param {Script} script that is being changed
// @param {Array} change_log a list that collects engineer-readable description
// of what happened.
Debug.LiveEditChangeScript = function(script, change_pos, change_len, new_str,
change_log) {
// So far the function works as namespace.
var liveedit = Debug.LiveEditChangeScript;
var Assert = liveedit.Assert;
// Fully compiles source string as a script. Returns Array of
// FunctionCompileInfo -- a descriptions of all functions of the script.
// Elements of array are ordered by start positions of functions (from top
// to bottom) in the source. Fields outer_index and next_sibling_index help
// to navigate the nesting structure of functions.
//
// The script is used for compilation, because it produces code that
// needs to be linked with some particular script (for nested functions).
function DebugGatherCompileInfo(source) {
// Get function info, elements are partially sorted (it is a tree
// of nested functions serialized as parent followed by serialized children.
var raw_compile_info = %LiveEditGatherCompileInfo(script, source);
// Sort function infos by start position field.
var compile_info = new Array();
var old_index_map = new Array();
for (var i = 0; i < raw_compile_info.length; i++) {
compile_info.push(new liveedit.FunctionCompileInfo(raw_compile_info[i]));
old_index_map.push(i);
}
for (var i = 0; i < compile_info.length; i++) {
var k = i;
for (var j = i + 1; j < compile_info.length; j++) {
if (compile_info[k].start_position > compile_info[j].start_position) {
k = j;
}
}
if (k != i) {
var temp_info = compile_info[k];
var temp_index = old_index_map[k];
compile_info[k] = compile_info[i];
old_index_map[k] = old_index_map[i];
compile_info[i] = temp_info;
old_index_map[i] = temp_index;
}
}
// After sorting update outer_inder field using old_index_map. Also
// set next_sibling_index field.
var current_index = 0;
// The recursive function, that goes over all children of a particular
// node (i.e. function info).
function ResetIndexes(new_parent_index, old_parent_index) {
var previous_sibling = -1;
while (current_index < compile_info.length &&
compile_info[current_index].outer_index == old_parent_index) {
var saved_index = current_index;
compile_info[saved_index].outer_index = new_parent_index;
if (previous_sibling != -1) {
compile_info[previous_sibling].next_sibling_index = saved_index;
}
previous_sibling = saved_index;
current_index++;
ResetIndexes(saved_index, old_index_map[saved_index]);
}
if (previous_sibling != -1) {
compile_info[previous_sibling].next_sibling_index = -1;
}
}
ResetIndexes(-1, -1);
Assert(current_index == compile_info.length);
return compile_info;
}
// Given a positions, finds a function that fully includes the entire change.
function FindChangedFunction(compile_info, offset, len) {
// First condition: function should start before the change region.
// Function #0 (whole-script function) always does, but we want
// one, that is later in this list.
var index = 0;
while (index + 1 < compile_info.length &&
compile_info[index + 1].start_position <= offset) {
index++;
}
// Now we are at the last function that begins before the change
// region. The function that covers entire change region is either
// this function or the enclosing one.
for (; compile_info[index].end_position < offset + len;
index = compile_info[index].outer_index) {
Assert(index != -1);
}
return index;
}
// Variable forward declarations. Preprocessor "Minifier" needs them.
var old_compile_info;
var shared_infos;
// Finds SharedFunctionInfo that corresponds compile info with index
// in old version of the script.
function FindFunctionInfo(index) {
var old_info = old_compile_info[index];
for (var i = 0; i < shared_infos.length; i++) {
var info = shared_infos[i];
if (info.start_position == old_info.start_position &&
info.end_position == old_info.end_position) {
return info;
}
}
}
// Replaces function's Code.
function PatchCode(new_info, shared_info) {
%LiveEditReplaceFunctionCode(new_info.raw_array, shared_info.raw_array);
change_log.push( {function_patched: new_info.function_name} );
}
var change_len_old;
var change_len_new;
// Translate position in old version of script into position in new
// version of script.
function PosTranslator(old_pos) {
if (old_pos <= change_pos) {
return old_pos;
}
if (old_pos >= change_pos + change_len_old) {
return old_pos + change_len_new - change_len_old;
}
return -1;
}
var position_change_array;
var position_patch_report;
function PatchPositions(new_info, shared_info) {
if (!shared_info) {
// TODO: explain what is happening.
return;
}
%LiveEditPatchFunctionPositions(shared_info.raw_array,
position_change_array);
position_patch_report.push( { name: new_info.function_name } );
}
var link_to_old_script_report;
var old_script;
// Makes a function associated with another instance of a script (the
// one representing its old version). This way the function still
// may access its own text.
function LinkToOldScript(shared_info) {
%LiveEditRelinkFunctionToScript(shared_info.raw_array, old_script);
link_to_old_script_report.push( { name: shared_info.function_name } );
}
var old_source = script.source;
var change_len_old = change_len;
var change_len_new = new_str.length;
// Prepare new source string.
var new_source = old_source.substring(0, change_pos) +
new_str + old_source.substring(change_pos + change_len);
// Find all SharedFunctionInfo's that are compiled from this script.
var shared_raw_list = %LiveEditFindSharedFunctionInfosForScript(script);
var shared_infos = new Array();
for (var i = 0; i < shared_raw_list.length; i++) {
shared_infos.push(new liveedit.SharedInfoWrapper(shared_raw_list[i]));
}
// Gather compile information about old version of script.
var old_compile_info = DebugGatherCompileInfo(old_source);
// Gather compile information about new version of script.
var new_compile_info;
try {
new_compile_info = DebugGatherCompileInfo(new_source);
} catch (e) {
throw new liveedit.Failure("Failed to compile new version of script: " + e);
}
// An index of a single function, that is going to have its code replaced.
var function_being_patched =
FindChangedFunction(old_compile_info, change_pos, change_len_old);
// In old and new script versions function with a change should have the
// same indexes.
var function_being_patched2 =
FindChangedFunction(new_compile_info, change_pos, change_len_new);
Assert(function_being_patched == function_being_patched2,
"inconsistent old/new compile info");
// Check that function being patched has the same expectations in a new
// version. Otherwise we cannot safely patch its behavior and should
// choose the outer function instead.
while (!liveedit.CompareFunctionExpectations(
old_compile_info[function_being_patched],
new_compile_info[function_being_patched])) {
Assert(old_compile_info[function_being_patched].outer_index ==
new_compile_info[function_being_patched].outer_index);
function_being_patched =
old_compile_info[function_being_patched].outer_index;
Assert(function_being_patched != -1);
}
// Check that function being patched is not currently on stack.
liveedit.CheckStackActivations(
[ FindFunctionInfo(function_being_patched) ], change_log );
// Committing all changes.
var old_script_name = liveedit.CreateNameForOldScript(script);
// Update the script text and create a new script representing an old
// version of the script.
var old_script = %LiveEditReplaceScript(script, new_source, old_script_name);
PatchCode(new_compile_info[function_being_patched],
FindFunctionInfo(function_being_patched));
var position_patch_report = new Array();
change_log.push( {position_patched: position_patch_report} );
var position_change_array = [ change_pos,
change_pos + change_len_old,
change_pos + change_len_new ];
// Update positions of all outer functions (i.e. all functions, that
// are partially below the function being patched).
for (var i = new_compile_info[function_being_patched].outer_index;
i != -1;
i = new_compile_info[i].outer_index) {
PatchPositions(new_compile_info[i], FindFunctionInfo(i));
}
// Update positions of all functions that are fully below the function
// being patched.
var old_next_sibling =
old_compile_info[function_being_patched].next_sibling_index;
var new_next_sibling =
new_compile_info[function_being_patched].next_sibling_index;
// We simply go over the tail of both old and new lists. Their tails should
// have an identical structure.
if (old_next_sibling == -1) {
Assert(new_next_sibling == -1);
} else {
Assert(old_compile_info.length - old_next_sibling ==
new_compile_info.length - new_next_sibling);
for (var i = old_next_sibling, j = new_next_sibling;
i < old_compile_info.length; i++, j++) {
PatchPositions(new_compile_info[j], FindFunctionInfo(i));
}
}
var link_to_old_script_report = new Array();
change_log.push( { linked_to_old_script: link_to_old_script_report } );
// We need to link to old script all former nested functions.
for (var i = function_being_patched + 1; i < old_next_sibling; i++) {
LinkToOldScript(FindFunctionInfo(i), old_script);
}
}
Debug.LiveEditChangeScript.Assert = function(condition, message) {
if (!condition) {
if (message) {
throw "Assert " + message;
} else {
throw "Assert";
}
}
}
// An object describing function compilation details. Its index fields
// apply to indexes inside array that stores these objects.
Debug.LiveEditChangeScript.FunctionCompileInfo = function(raw_array) {
this.function_name = raw_array[0];
this.start_position = raw_array[1];
this.end_position = raw_array[2];
this.param_num = raw_array[3];
this.code = raw_array[4];
this.scope_info = raw_array[5];
this.outer_index = raw_array[6];
this.next_sibling_index = null;
this.raw_array = raw_array;
}
// A structure describing SharedFunctionInfo.
Debug.LiveEditChangeScript.SharedInfoWrapper = function(raw_array) {
this.function_name = raw_array[0];
this.start_position = raw_array[1];
this.end_position = raw_array[2];
this.info = raw_array[3];
this.raw_array = raw_array;
}
// Adds a suffix to script name to mark that it is old version.
Debug.LiveEditChangeScript.CreateNameForOldScript = function(script) {
// TODO(635): try better than this; support several changes.
return script.name + " (old)";
}
// Compares a function interface old and new version, whether it
// changed or not.
Debug.LiveEditChangeScript.CompareFunctionExpectations =
function(function_info1, function_info2) {
// Check that function has the same number of parameters (there may exist
// an adapter, that won't survive function parameter number change).
if (function_info1.param_num != function_info2.param_num) {
return false;
}
var scope_info1 = function_info1.scope_info;
var scope_info2 = function_info2.scope_info;
if (!scope_info1) {
return !scope_info2;
}
if (scope_info1.length != scope_info2.length) {
return false;
}
// Check that outer scope structure is not changed. Otherwise the function
// will not properly work with existing scopes.
return scope_info1.toString() == scope_info2.toString();
}
// For array of wrapped shared function infos checks that none of them
// have activations on stack (of any thread). Throws a Failure exception
// if this proves to be false.
Debug.LiveEditChangeScript.CheckStackActivations = function(shared_wrapper_list,
change_log) {
var liveedit = Debug.LiveEditChangeScript;
var shared_list = new Array();
for (var i = 0; i < shared_wrapper_list.length; i++) {
shared_list[i] = shared_wrapper_list[i].info;
}
var result = %LiveEditCheckStackActivations(shared_list);
var problems = new Array();
for (var i = 0; i < shared_list.length; i++) {
if (result[i] == liveedit.FunctionPatchabilityStatus.FUNCTION_BLOCKED_ON_STACK) {
var shared = shared_list[i];
var description = {
name: shared.function_name,
start_pos: shared.start_position,
end_pos: shared.end_position
};
problems.push(description);
}
}
if (problems.length > 0) {
change_log.push( { functions_on_stack: problems } );
throw new liveedit.Failure("Blocked by functions on stack");
}
}
// A copy of the FunctionPatchabilityStatus enum from liveedit.h
Debug.LiveEditChangeScript.FunctionPatchabilityStatus = {
FUNCTION_AVAILABLE_FOR_PATCH: 0,
FUNCTION_BLOCKED_ON_STACK: 1
}
// A logical failure in liveedit process. This means that change_log
// is valid and consistent description of what happened.
Debug.LiveEditChangeScript.Failure = function(message) {
this.message = message;
}
Debug.LiveEditChangeScript.Failure.prototype.toString = function() {
return "LiveEdit Failure: " + this.message;
}
// A testing entry.
Debug.LiveEditChangeScript.GetPcFromSourcePos = function(func, source_pos) {
return %GetFunctionCodePositionFromSource(func, source_pos);
}