Format
Review URL: http://codereview.chromium.org/1589036 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4420 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
parent
0e9149c543
commit
7721e484e9
@ -31,443 +31,439 @@
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// A LiveEdit namespace is declared inside a single function constructor.
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Debug.LiveEdit = new function() {
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// TODO(LiveEdit): restore indentation below
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// Changes script text and recompiles all relevant functions if possible.
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// The change is always a substring (change_pos, change_pos + change_len)
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// being replaced with a completely different string new_str.
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//
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// Only one function will have its Code changed in result of this function.
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// All nested functions (should they have any instances at the moment) are left
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// unchanged and re-linked to a newly created script instance representing old
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// version of the source. (Generally speaking,
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// during the change all nested functions are erased and completely different
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// set of nested functions are introduced.) All other functions just have
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// their positions updated.
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//
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// @param {Script} script that is being changed
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// @param {Array} change_log a list that collects engineer-readable description
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// of what happened.
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function ApplyPatch(script, change_pos, change_len, new_str,
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change_log) {
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// Fully compiles source string as a script. Returns Array of
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// FunctionCompileInfo -- a descriptions of all functions of the script.
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// Elements of array are ordered by start positions of functions (from top
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// to bottom) in the source. Fields outer_index and next_sibling_index help
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// to navigate the nesting structure of functions.
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// Changes script text and recompiles all relevant functions if possible.
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// The change is always a substring (change_pos, change_pos + change_len)
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// being replaced with a completely different string new_str.
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//
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// The script is used for compilation, because it produces code that
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// needs to be linked with some particular script (for nested functions).
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function DebugGatherCompileInfo(source) {
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// Get function info, elements are partially sorted (it is a tree
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// of nested functions serialized as parent followed by serialized children.
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var raw_compile_info = %LiveEditGatherCompileInfo(script, source);
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// Sort function infos by start position field.
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var compile_info = new Array();
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var old_index_map = new Array();
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for (var i = 0; i < raw_compile_info.length; i++) {
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compile_info.push(new FunctionCompileInfo(raw_compile_info[i]));
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old_index_map.push(i);
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}
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for (var i = 0; i < compile_info.length; i++) {
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var k = i;
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for (var j = i + 1; j < compile_info.length; j++) {
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if (compile_info[k].start_position > compile_info[j].start_position) {
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k = j;
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}
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}
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if (k != i) {
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var temp_info = compile_info[k];
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var temp_index = old_index_map[k];
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compile_info[k] = compile_info[i];
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old_index_map[k] = old_index_map[i];
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compile_info[i] = temp_info;
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old_index_map[i] = temp_index;
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}
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}
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// After sorting update outer_inder field using old_index_map. Also
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// set next_sibling_index field.
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var current_index = 0;
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// The recursive function, that goes over all children of a particular
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// node (i.e. function info).
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function ResetIndexes(new_parent_index, old_parent_index) {
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var previous_sibling = -1;
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while (current_index < compile_info.length &&
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compile_info[current_index].outer_index == old_parent_index) {
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var saved_index = current_index;
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compile_info[saved_index].outer_index = new_parent_index;
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if (previous_sibling != -1) {
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compile_info[previous_sibling].next_sibling_index = saved_index;
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}
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previous_sibling = saved_index;
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current_index++;
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ResetIndexes(saved_index, old_index_map[saved_index]);
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}
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if (previous_sibling != -1) {
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compile_info[previous_sibling].next_sibling_index = -1;
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}
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}
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ResetIndexes(-1, -1);
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Assert(current_index == compile_info.length);
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return compile_info;
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}
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// Given a positions, finds a function that fully includes the entire change.
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function FindChangedFunction(compile_info, offset, len) {
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// First condition: function should start before the change region.
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// Function #0 (whole-script function) always does, but we want
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// one, that is later in this list.
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var index = 0;
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while (index + 1 < compile_info.length &&
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compile_info[index + 1].start_position <= offset) {
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index++;
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}
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// Now we are at the last function that begins before the change
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// region. The function that covers entire change region is either
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// this function or the enclosing one.
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for (; compile_info[index].end_position < offset + len;
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index = compile_info[index].outer_index) {
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Assert(index != -1);
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}
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return index;
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}
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// Variable forward declarations. Preprocessor "Minifier" needs them.
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var old_compile_info;
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var shared_infos;
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// Finds SharedFunctionInfo that corresponds compile info with index
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// in old version of the script.
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function FindFunctionInfo(index) {
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var old_info = old_compile_info[index];
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for (var i = 0; i < shared_infos.length; i++) {
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var info = shared_infos[i];
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if (info.start_position == old_info.start_position &&
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info.end_position == old_info.end_position) {
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return info;
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}
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}
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}
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// Replaces function's Code.
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function PatchCode(new_info, shared_info) {
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%LiveEditReplaceFunctionCode(new_info.raw_array, shared_info.raw_array);
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change_log.push( {function_patched: new_info.function_name} );
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}
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var change_len_old;
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var change_len_new;
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// Translate position in old version of script into position in new
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// version of script.
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function PosTranslator(old_pos) {
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if (old_pos <= change_pos) {
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return old_pos;
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}
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if (old_pos >= change_pos + change_len_old) {
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return old_pos + change_len_new - change_len_old;
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}
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return -1;
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}
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var position_change_array;
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var position_patch_report;
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function PatchPositions(new_info, shared_info) {
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if (!shared_info) {
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// TODO(LiveEdit): explain what is happening.
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return;
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}
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var breakpoint_position_update = %LiveEditPatchFunctionPositions(
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shared_info.raw_array, position_change_array);
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for (var i = 0; i < breakpoint_position_update.length; i += 2) {
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var new_pos = breakpoint_position_update[i];
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var break_point_object = breakpoint_position_update[i + 1];
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change_log.push( { breakpoint_position_update:
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{ from: break_point_object.source_position(), to: new_pos } } );
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break_point_object.updateSourcePosition(new_pos, script);
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}
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position_patch_report.push( { name: new_info.function_name } );
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}
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var link_to_old_script_report;
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var old_script;
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// Makes a function associated with another instance of a script (the
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// one representing its old version). This way the function still
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// may access its own text.
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function LinkToOldScript(shared_info) {
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%LiveEditRelinkFunctionToScript(shared_info.raw_array, old_script);
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link_to_old_script_report.push( { name: shared_info.function_name } );
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}
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var old_source = script.source;
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var change_len_old = change_len;
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var change_len_new = new_str.length;
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// Prepare new source string.
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var new_source = old_source.substring(0, change_pos) +
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new_str + old_source.substring(change_pos + change_len);
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// Find all SharedFunctionInfo's that are compiled from this script.
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var shared_raw_list = %LiveEditFindSharedFunctionInfosForScript(script);
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var shared_infos = new Array();
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for (var i = 0; i < shared_raw_list.length; i++) {
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shared_infos.push(new SharedInfoWrapper(shared_raw_list[i]));
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}
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// Gather compile information about old version of script.
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var old_compile_info = DebugGatherCompileInfo(old_source);
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// Gather compile information about new version of script.
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var new_compile_info;
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try {
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new_compile_info = DebugGatherCompileInfo(new_source);
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} catch (e) {
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throw new Failure("Failed to compile new version of script: " + e);
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}
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// An index of a single function, that is going to have its code replaced.
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var function_being_patched =
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FindChangedFunction(old_compile_info, change_pos, change_len_old);
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// In old and new script versions function with a change should have the
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// same indexes.
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var function_being_patched2 =
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FindChangedFunction(new_compile_info, change_pos, change_len_new);
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Assert(function_being_patched == function_being_patched2,
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"inconsistent old/new compile info");
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// Check that function being patched has the same expectations in a new
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// version. Otherwise we cannot safely patch its behavior and should
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// choose the outer function instead.
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while (!CompareFunctionExpectations(
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old_compile_info[function_being_patched],
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new_compile_info[function_being_patched])) {
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Assert(old_compile_info[function_being_patched].outer_index ==
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new_compile_info[function_being_patched].outer_index);
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function_being_patched =
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old_compile_info[function_being_patched].outer_index;
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Assert(function_being_patched != -1);
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}
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// Check that function being patched is not currently on stack.
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CheckStackActivations(
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[ FindFunctionInfo(function_being_patched) ], change_log );
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// Committing all changes.
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var old_script_name = CreateNameForOldScript(script);
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// Update the script text and create a new script representing an old
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// version of the script.
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var old_script = %LiveEditReplaceScript(script, new_source, old_script_name);
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PatchCode(new_compile_info[function_being_patched],
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FindFunctionInfo(function_being_patched));
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var position_patch_report = new Array();
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change_log.push( {position_patched: position_patch_report} );
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var position_change_array = [ change_pos,
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change_pos + change_len_old,
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change_pos + change_len_new ];
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// Update positions of all outer functions (i.e. all functions, that
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// are partially below the function being patched).
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for (var i = new_compile_info[function_being_patched].outer_index;
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i != -1;
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i = new_compile_info[i].outer_index) {
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PatchPositions(new_compile_info[i], FindFunctionInfo(i));
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}
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// Update positions of all functions that are fully below the function
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// being patched.
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var old_next_sibling =
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old_compile_info[function_being_patched].next_sibling_index;
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var new_next_sibling =
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new_compile_info[function_being_patched].next_sibling_index;
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// We simply go over the tail of both old and new lists. Their tails should
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// have an identical structure.
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if (old_next_sibling == -1) {
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Assert(new_next_sibling == -1);
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} else {
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Assert(old_compile_info.length - old_next_sibling ==
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new_compile_info.length - new_next_sibling);
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for (var i = old_next_sibling, j = new_next_sibling;
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i < old_compile_info.length; i++, j++) {
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PatchPositions(new_compile_info[j], FindFunctionInfo(i));
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}
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}
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var link_to_old_script_report = new Array();
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change_log.push( { linked_to_old_script: link_to_old_script_report } );
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// We need to link to old script all former nested functions.
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for (var i = function_being_patched + 1; i < old_next_sibling; i++) {
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LinkToOldScript(FindFunctionInfo(i), old_script);
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}
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}
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// Function is public.
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this.ApplyPatch = ApplyPatch;
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function Assert(condition, message) {
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if (!condition) {
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if (message) {
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throw "Assert " + message;
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} else {
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throw "Assert";
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}
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}
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}
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// An object describing function compilation details. Its index fields
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// apply to indexes inside array that stores these objects.
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function FunctionCompileInfo(raw_array) {
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this.function_name = raw_array[0];
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this.start_position = raw_array[1];
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this.end_position = raw_array[2];
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this.param_num = raw_array[3];
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this.code = raw_array[4];
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this.scope_info = raw_array[5];
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this.outer_index = raw_array[6];
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this.next_sibling_index = null;
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this.raw_array = raw_array;
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}
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function SharedInfoWrapper(raw_array) {
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this.function_name = raw_array[0];
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this.start_position = raw_array[1];
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this.end_position = raw_array[2];
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this.info = raw_array[3];
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this.raw_array = raw_array;
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}
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// Adds a suffix to script name to mark that it is old version.
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function CreateNameForOldScript(script) {
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// TODO(635): try better than this; support several changes.
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return script.name + " (old)";
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}
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// Compares a function interface old and new version, whether it
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// changed or not.
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function CompareFunctionExpectations(function_info1, function_info2) {
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// Check that function has the same number of parameters (there may exist
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// an adapter, that won't survive function parameter number change).
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if (function_info1.param_num != function_info2.param_num) {
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return false;
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}
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var scope_info1 = function_info1.scope_info;
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var scope_info2 = function_info2.scope_info;
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if (!scope_info1) {
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return !scope_info2;
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}
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if (scope_info1.length != scope_info2.length) {
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return false;
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}
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// Check that outer scope structure is not changed. Otherwise the function
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// will not properly work with existing scopes.
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return scope_info1.toString() == scope_info2.toString();
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}
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// Minifier forward declaration.
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var FunctionPatchabilityStatus;
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// For array of wrapped shared function infos checks that none of them
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// have activations on stack (of any thread). Throws a Failure exception
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// if this proves to be false.
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function CheckStackActivations(shared_wrapper_list, change_log) {
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var shared_list = new Array();
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for (var i = 0; i < shared_wrapper_list.length; i++) {
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shared_list[i] = shared_wrapper_list[i].info;
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}
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var result = %LiveEditCheckAndDropActivations(shared_list, true);
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if (result[shared_list.length]) {
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// Extra array element may contain error message.
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throw new Failure(result[shared_list.length]);
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}
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||||
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var problems = new Array();
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var dropped = new Array();
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||||
for (var i = 0; i < shared_list.length; i++) {
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var shared = shared_wrapper_list[i];
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if (result[i] == FunctionPatchabilityStatus.REPLACED_ON_ACTIVE_STACK) {
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dropped.push({ name: shared.function_name } );
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} else if (result[i] != FunctionPatchabilityStatus.AVAILABLE_FOR_PATCH) {
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||||
var description = {
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name: shared.function_name,
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start_pos: shared.start_position,
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end_pos: shared.end_position,
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||||
replace_problem:
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||||
FunctionPatchabilityStatus.SymbolName(result[i])
|
||||
};
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||||
problems.push(description);
|
||||
}
|
||||
}
|
||||
if (dropped.length > 0) {
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||||
change_log.push({ dropped_from_stack: dropped });
|
||||
}
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||||
if (problems.length > 0) {
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||||
change_log.push( { functions_on_stack: problems } );
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||||
throw new Failure("Blocked by functions on stack");
|
||||
}
|
||||
}
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||||
|
||||
// A copy of the FunctionPatchabilityStatus enum from liveedit.h
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var FunctionPatchabilityStatus = {
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AVAILABLE_FOR_PATCH: 1,
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BLOCKED_ON_ACTIVE_STACK: 2,
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BLOCKED_ON_OTHER_STACK: 3,
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BLOCKED_UNDER_NATIVE_CODE: 4,
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REPLACED_ON_ACTIVE_STACK: 5
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}
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||||
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FunctionPatchabilityStatus.SymbolName = function(code) {
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||||
var enum = FunctionPatchabilityStatus;
|
||||
for (name in enum) {
|
||||
if (enum[name] == code) {
|
||||
return name;
|
||||
}
|
||||
}
|
||||
}
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||||
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||||
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||||
// A logical failure in liveedit process. This means that change_log
|
||||
// is valid and consistent description of what happened.
|
||||
function Failure(message) {
|
||||
this.message = message;
|
||||
}
|
||||
// Function (constructor) is public.
|
||||
this.Failure = Failure;
|
||||
|
||||
Failure.prototype.toString = function() {
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||||
return "LiveEdit Failure: " + this.message;
|
||||
}
|
||||
|
||||
// A testing entry.
|
||||
function GetPcFromSourcePos(func, source_pos) {
|
||||
return %GetFunctionCodePositionFromSource(func, source_pos);
|
||||
}
|
||||
// Function is public.
|
||||
this.GetPcFromSourcePos = GetPcFromSourcePos;
|
||||
|
||||
// TODO(LiveEdit): restore indentation above
|
||||
// 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.
|
||||
function ApplyPatch(script, change_pos, change_len, new_str,
|
||||
change_log) {
|
||||
|
||||
// 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 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(LiveEdit): explain what is happening.
|
||||
return;
|
||||
}
|
||||
var breakpoint_position_update = %LiveEditPatchFunctionPositions(
|
||||
shared_info.raw_array, position_change_array);
|
||||
for (var i = 0; i < breakpoint_position_update.length; i += 2) {
|
||||
var new_pos = breakpoint_position_update[i];
|
||||
var break_point_object = breakpoint_position_update[i + 1];
|
||||
change_log.push( { breakpoint_position_update:
|
||||
{ from: break_point_object.source_position(), to: new_pos } } );
|
||||
break_point_object.updateSourcePosition(new_pos, script);
|
||||
}
|
||||
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 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 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 (!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.
|
||||
CheckStackActivations(
|
||||
[ FindFunctionInfo(function_being_patched) ], change_log );
|
||||
|
||||
|
||||
// Committing all changes.
|
||||
var old_script_name = 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);
|
||||
}
|
||||
}
|
||||
// Function is public.
|
||||
this.ApplyPatch = ApplyPatch;
|
||||
|
||||
function Assert(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.
|
||||
function FunctionCompileInfo(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;
|
||||
}
|
||||
|
||||
function SharedInfoWrapper(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.
|
||||
function CreateNameForOldScript(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.
|
||||
function CompareFunctionExpectations(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();
|
||||
}
|
||||
|
||||
// Minifier forward declaration.
|
||||
var FunctionPatchabilityStatus;
|
||||
|
||||
// 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.
|
||||
function CheckStackActivations(shared_wrapper_list, change_log) {
|
||||
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 = %LiveEditCheckAndDropActivations(shared_list, true);
|
||||
if (result[shared_list.length]) {
|
||||
// Extra array element may contain error message.
|
||||
throw new Failure(result[shared_list.length]);
|
||||
}
|
||||
|
||||
var problems = new Array();
|
||||
var dropped = new Array();
|
||||
for (var i = 0; i < shared_list.length; i++) {
|
||||
var shared = shared_wrapper_list[i];
|
||||
if (result[i] == FunctionPatchabilityStatus.REPLACED_ON_ACTIVE_STACK) {
|
||||
dropped.push({ name: shared.function_name } );
|
||||
} else if (result[i] != FunctionPatchabilityStatus.AVAILABLE_FOR_PATCH) {
|
||||
var description = {
|
||||
name: shared.function_name,
|
||||
start_pos: shared.start_position,
|
||||
end_pos: shared.end_position,
|
||||
replace_problem:
|
||||
FunctionPatchabilityStatus.SymbolName(result[i])
|
||||
};
|
||||
problems.push(description);
|
||||
}
|
||||
}
|
||||
if (dropped.length > 0) {
|
||||
change_log.push({ dropped_from_stack: dropped });
|
||||
}
|
||||
if (problems.length > 0) {
|
||||
change_log.push( { functions_on_stack: problems } );
|
||||
throw new Failure("Blocked by functions on stack");
|
||||
}
|
||||
}
|
||||
|
||||
// A copy of the FunctionPatchabilityStatus enum from liveedit.h
|
||||
var FunctionPatchabilityStatus = {
|
||||
AVAILABLE_FOR_PATCH: 1,
|
||||
BLOCKED_ON_ACTIVE_STACK: 2,
|
||||
BLOCKED_ON_OTHER_STACK: 3,
|
||||
BLOCKED_UNDER_NATIVE_CODE: 4,
|
||||
REPLACED_ON_ACTIVE_STACK: 5
|
||||
}
|
||||
|
||||
FunctionPatchabilityStatus.SymbolName = function(code) {
|
||||
var enum = FunctionPatchabilityStatus;
|
||||
for (name in enum) {
|
||||
if (enum[name] == code) {
|
||||
return name;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
// A logical failure in liveedit process. This means that change_log
|
||||
// is valid and consistent description of what happened.
|
||||
function Failure(message) {
|
||||
this.message = message;
|
||||
}
|
||||
// Function (constructor) is public.
|
||||
this.Failure = Failure;
|
||||
|
||||
Failure.prototype.toString = function() {
|
||||
return "LiveEdit Failure: " + this.message;
|
||||
}
|
||||
|
||||
// A testing entry.
|
||||
function GetPcFromSourcePos(func, source_pos) {
|
||||
return %GetFunctionCodePositionFromSource(func, source_pos);
|
||||
}
|
||||
// Function is public.
|
||||
this.GetPcFromSourcePos = GetPcFromSourcePos;
|
||||
|
||||
// LiveEdit main entry point: changes a script text to a new string.
|
||||
function SetScriptSource(script, new_source, change_log) {
|
||||
var old_source = script.source;
|
||||
|
Loading…
Reference in New Issue
Block a user