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-rw-r--r--js/src/devtools/rootAnalysis/analyzeRoots.js871
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diff --git a/js/src/devtools/rootAnalysis/analyzeRoots.js b/js/src/devtools/rootAnalysis/analyzeRoots.js
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+++ b/js/src/devtools/rootAnalysis/analyzeRoots.js
@@ -0,0 +1,871 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 4 -*- */
+
+"use strict";
+
+loadRelativeToScript('utility.js');
+loadRelativeToScript('annotations.js');
+loadRelativeToScript('CFG.js');
+
+var sourceRoot = (os.getenv('SOURCE') || '') + '/'
+
+var functionName;
+var functionBodies;
+
+if (typeof scriptArgs[0] != 'string' || typeof scriptArgs[1] != 'string')
+ throw "Usage: analyzeRoots.js [-f function_name] <gcFunctions.lst> <gcEdges.txt> <suppressedFunctions.lst> <gcTypes.txt> <typeInfo.txt> [start end [tmpfile]]";
+
+var theFunctionNameToFind;
+if (scriptArgs[0] == '--function' || scriptArgs[0] == '-f') {
+ theFunctionNameToFind = scriptArgs[1];
+ scriptArgs = scriptArgs.slice(2);
+}
+
+var gcFunctionsFile = scriptArgs[0] || "gcFunctions.lst";
+var gcEdgesFile = scriptArgs[1] || "gcEdges.txt";
+var suppressedFunctionsFile = scriptArgs[2] || "suppressedFunctions.lst";
+var gcTypesFile = scriptArgs[3] || "gcTypes.txt";
+var typeInfoFile = scriptArgs[4] || "typeInfo.txt";
+var batch = (scriptArgs[5]|0) || 1;
+var numBatches = (scriptArgs[6]|0) || 1;
+var tmpfile = scriptArgs[7] || "tmp.txt";
+
+GCSuppressionTypes = loadTypeInfo(typeInfoFile)["Suppress GC"] || [];
+
+var gcFunctions = {};
+var text = snarf("gcFunctions.lst").split("\n");
+assert(text.pop().length == 0);
+for (var line of text)
+ gcFunctions[mangled(line)] = true;
+
+var suppressedFunctions = {};
+var text = snarf(suppressedFunctionsFile).split("\n");
+assert(text.pop().length == 0);
+for (var line of text) {
+ suppressedFunctions[line] = true;
+}
+text = null;
+
+var gcEdges = {};
+text = snarf(gcEdgesFile).split('\n');
+assert(text.pop().length == 0);
+for (var line of text) {
+ var [ block, edge, func ] = line.split(" || ");
+ if (!(block in gcEdges))
+ gcEdges[block] = {}
+ gcEdges[block][edge] = func;
+}
+text = null;
+
+var match;
+var gcThings = {};
+var gcPointers = {};
+
+text = snarf(gcTypesFile).split("\n");
+for (var line of text) {
+ if (match = /^GCThing: (.*)/.exec(line))
+ gcThings[match[1]] = true;
+ if (match = /^GCPointer: (.*)/.exec(line))
+ gcPointers[match[1]] = true;
+}
+text = null;
+
+function isGCType(type)
+{
+ if (type.Kind == "CSU")
+ return type.Name in gcThings;
+ else if (type.Kind == "Array")
+ return isGCType(type.Type);
+ return false;
+}
+
+function isUnrootedType(type)
+{
+ if (type.Kind == "Pointer")
+ return isGCType(type.Type);
+ else if (type.Kind == "Array")
+ return isUnrootedType(type.Type);
+ else if (type.Kind == "CSU")
+ return type.Name in gcPointers;
+ else
+ return false;
+}
+
+function expressionUsesVariable(exp, variable)
+{
+ if (exp.Kind == "Var" && sameVariable(exp.Variable, variable))
+ return true;
+ if (!("Exp" in exp))
+ return false;
+ for (var childExp of exp.Exp) {
+ if (expressionUsesVariable(childExp, variable))
+ return true;
+ }
+ return false;
+}
+
+function expressionUsesVariableContents(exp, variable)
+{
+ if (!("Exp" in exp))
+ return false;
+ for (var childExp of exp.Exp) {
+ if (childExp.Kind == 'Drf') {
+ if (expressionUsesVariable(childExp, variable))
+ return true;
+ } else if (expressionUsesVariableContents(childExp, variable)) {
+ return true;
+ }
+ }
+ return false;
+}
+
+// Detect simple |return nullptr;| statements.
+function isReturningImmobileValue(edge, variable)
+{
+ if (variable.Kind == "Return") {
+ if (edge.Exp[0].Kind == "Var" && sameVariable(edge.Exp[0].Variable, variable)) {
+ if (edge.Exp[1].Kind == "Int" && edge.Exp[1].String == "0") {
+ return true;
+ }
+ }
+ }
+ return false;
+}
+
+// If the edge uses the given variable's value, return the earliest point at
+// which the use is definite. Usually, that means the source of the edge
+// (anything that reaches that source point will end up using the variable, but
+// there may be other ways to reach the destination of the edge.)
+//
+// Return values are implicitly used at the very last point in the function.
+// This makes a difference: if an RAII class GCs in its destructor, we need to
+// start looking at the final point in the function, not one point back from
+// that, since that would skip over the GCing call.
+//
+// Note that this returns true only if the variable's incoming value is used.
+// So this would return false for 'obj':
+//
+// obj = someFunction();
+//
+// but these would return true:
+//
+// obj = someFunction(obj);
+// obj->foo = someFunction();
+//
+function edgeUsesVariable(edge, variable, body)
+{
+ if (ignoreEdgeUse(edge, variable, body))
+ return 0;
+
+ if (variable.Kind == "Return" && body.Index[1] == edge.Index[1] && body.BlockId.Kind == "Function")
+ return edge.Index[1]; // Last point in function body uses the return value.
+
+ var src = edge.Index[0];
+
+ switch (edge.Kind) {
+
+ case "Assign": {
+ if (isReturningImmobileValue(edge, variable))
+ return 0;
+ const [lhs, rhs] = edge.Exp;
+ if (expressionUsesVariable(rhs, variable))
+ return src;
+ if (expressionUsesVariable(lhs, variable) && !expressionIsVariable(lhs, variable))
+ return src;
+ return 0;
+ }
+
+ case "Assume":
+ return expressionUsesVariableContents(edge.Exp[0], variable) ? src : 0;
+
+ case "Call": {
+ const callee = edge.Exp[0];
+ if (expressionUsesVariable(callee, variable))
+ return src;
+ if ("PEdgeCallInstance" in edge) {
+ if (expressionUsesVariable(edge.PEdgeCallInstance.Exp, variable)) {
+ if (edgeKillsVariable(edge, variable)) {
+ // If the variable is being constructed, then the incoming
+ // value is not used here; it didn't exist before
+ // construction. (The analysis doesn't get told where
+ // variables are defined, so must infer it from
+ // construction. If the variable does not have a
+ // constructor, its live range may be larger than it really
+ // ought to be if it is defined within a loop body, but
+ // that is conservative.)
+ } else {
+ return src;
+ }
+ }
+ }
+ if ("PEdgeCallArguments" in edge) {
+ for (var exp of edge.PEdgeCallArguments.Exp) {
+ if (expressionUsesVariable(exp, variable))
+ return src;
+ }
+ }
+ if (edge.Exp.length == 1)
+ return 0;
+
+ // Assigning call result to a variable.
+ const lhs = edge.Exp[1];
+ if (expressionUsesVariable(lhs, variable) && !expressionIsVariable(lhs, variable))
+ return src;
+ return 0;
+ }
+
+ case "Loop":
+ return 0;
+
+ default:
+ assert(false);
+ }
+}
+
+function expressionIsVariableAddress(exp, variable)
+{
+ while (exp.Kind == "Fld")
+ exp = exp.Exp[0];
+ return exp.Kind == "Var" && sameVariable(exp.Variable, variable);
+}
+
+function edgeTakesVariableAddress(edge, variable, body)
+{
+ if (ignoreEdgeUse(edge, variable, body))
+ return false;
+ if (ignoreEdgeAddressTaken(edge))
+ return false;
+ switch (edge.Kind) {
+ case "Assign":
+ return expressionIsVariableAddress(edge.Exp[1], variable);
+ case "Call":
+ if ("PEdgeCallArguments" in edge) {
+ for (var exp of edge.PEdgeCallArguments.Exp) {
+ if (expressionIsVariableAddress(exp, variable))
+ return true;
+ }
+ }
+ return false;
+ default:
+ return false;
+ }
+}
+
+function expressionIsVariable(exp, variable)
+{
+ return exp.Kind == "Var" && sameVariable(exp.Variable, variable);
+}
+
+// Return whether the edge kills (overwrites) the variable's incoming value.
+// Examples of killing 'obj':
+//
+// obj = foo;
+// obj = foo();
+// obj = foo(obj); // uses previous value but then kills it
+// SomeClass obj(true, 1); // constructor
+//
+function edgeKillsVariable(edge, variable)
+{
+ // Direct assignments kill their lhs: var = value
+ if (edge.Kind == "Assign") {
+ const [lhs] = edge.Exp;
+ return (expressionIsVariable(lhs, variable) &&
+ !isReturningImmobileValue(edge, variable));
+ }
+
+ if (edge.Kind != "Call")
+ return false;
+
+ // Assignments of call results kill their lhs.
+ if (1 in edge.Exp) {
+ var lhs = edge.Exp[1];
+ if (expressionIsVariable(lhs, variable))
+ return true;
+ }
+
+ // Constructor calls kill their 'this' value.
+ if ("PEdgeCallInstance" in edge) {
+ var instance = edge.PEdgeCallInstance.Exp;
+
+ // Kludge around incorrect dereference on some constructor calls.
+ if (instance.Kind == "Drf")
+ instance = instance.Exp[0];
+
+ if (!expressionIsVariable(instance, variable))
+ return false;
+
+ var callee = edge.Exp[0];
+ if (callee.Kind != "Var")
+ return false;
+
+ assert(callee.Variable.Kind == "Func");
+ var calleeName = readable(callee.Variable.Name[0]);
+
+ // Constructor calls include the text 'Name::Name(' or 'Name<...>::Name('.
+ var openParen = calleeName.indexOf('(');
+ if (openParen < 0)
+ return false;
+ calleeName = calleeName.substring(0, openParen);
+
+ var lastColon = calleeName.lastIndexOf('::');
+ if (lastColon < 0)
+ return false;
+ var constructorName = calleeName.substr(lastColon + 2);
+ calleeName = calleeName.substr(0, lastColon);
+
+ var lastTemplateOpen = calleeName.lastIndexOf('<');
+ if (lastTemplateOpen >= 0)
+ calleeName = calleeName.substr(0, lastTemplateOpen);
+
+ if (calleeName.endsWith(constructorName))
+ return true;
+ }
+
+ return false;
+}
+
+function edgeCanGC(edge)
+{
+ if (edge.Kind != "Call")
+ return false;
+
+ var callee = edge.Exp[0];
+
+ while (callee.Kind == "Drf")
+ callee = callee.Exp[0];
+
+ if (callee.Kind == "Var") {
+ var variable = callee.Variable;
+
+ if (variable.Kind == "Func") {
+ var callee = mangled(variable.Name[0]);
+ if ((callee in gcFunctions) || ((callee + internalMarker) in gcFunctions))
+ return "'" + variable.Name[0] + "'";
+ return null;
+ }
+
+ var varName = variable.Name[0];
+ return indirectCallCannotGC(functionName, varName) ? null : "*" + varName;
+ }
+
+ if (callee.Kind == "Fld") {
+ var field = callee.Field;
+ var csuName = field.FieldCSU.Type.Name;
+ var fullFieldName = csuName + "." + field.Name[0];
+ if (fieldCallCannotGC(csuName, fullFieldName))
+ return null;
+ return (fullFieldName in suppressedFunctions) ? null : fullFieldName;
+ }
+}
+
+// Search recursively through predecessors from the use of a variable's value,
+// returning whether a GC call is reachable (in the reverse direction; this
+// means that the variable use is reachable from the GC call, and therefore the
+// variable is live after the GC call), along with some additional information.
+// What info we want depends on whether the variable turns out to be live
+// across a GC call. We are looking for both hazards (unrooted variables live
+// across GC calls) and unnecessary roots (rooted variables that have no GC
+// calls in their live ranges.)
+//
+// If not:
+//
+// - 'minimumUse': the earliest point in each body that uses the variable, for
+// reporting on unnecessary roots.
+//
+// If so:
+//
+// - 'why': a path from the GC call to a use of the variable after the GC
+// call, chained through a 'why' field in the returned edge descriptor
+//
+// - 'gcInfo': a direct pointer to the GC call edge
+//
+function findGCBeforeValueUse(start_body, start_point, suppressed, variable)
+{
+ // Scan through all edges preceding an unrooted variable use, using an
+ // explicit worklist, looking for a GC call. A worklist contains an
+ // incoming edge together with a description of where it or one of its
+ // successors GC'd (if any).
+
+ var bodies_visited = new Map();
+
+ let worklist = [{body: start_body, ppoint: start_point, preGCLive: false, gcInfo: null, why: null}];
+ while (worklist.length) {
+ // Grab an entry off of the worklist, representing a point within the
+ // CFG identified by <body,ppoint>. If this point has a descendant
+ // later in the CFG that can GC, gcInfo will be set to the information
+ // about that GC call.
+
+ var entry = worklist.pop();
+ var { body, ppoint, gcInfo, preGCLive } = entry;
+
+ // Handle the case where there are multiple ways to reach this point
+ // (traversing backwards).
+ var visited = bodies_visited.get(body);
+ if (!visited)
+ bodies_visited.set(body, visited = new Map());
+ if (visited.has(ppoint)) {
+ var seenEntry = visited.get(ppoint);
+
+ // This point already knows how to GC through some other path, so
+ // we have nothing new to learn. (The other path will consider the
+ // predecessors.)
+ if (seenEntry.gcInfo)
+ continue;
+
+ // If this worklist's entry doesn't know of any way to GC, then
+ // there's no point in continuing the traversal through it. Perhaps
+ // another edge will be found that *can* GC; otherwise, the first
+ // route to the point will traverse through predecessors.
+ //
+ // Note that this means we may visit a point more than once, if the
+ // first time we visit we don't have a known reachable GC call and
+ // the second time we do.
+ if (!gcInfo)
+ continue;
+ }
+ visited.set(ppoint, {body: body, gcInfo: gcInfo});
+
+ // Check for hitting the entry point of the current body (which may be
+ // the outer function or a loop within it.)
+ if (ppoint == body.Index[0]) {
+ if (body.BlockId.Kind == "Loop") {
+ // Propagate to outer body parents that enter the loop body.
+ if ("BlockPPoint" in body) {
+ for (var parent of body.BlockPPoint) {
+ var found = false;
+ for (var xbody of functionBodies) {
+ if (sameBlockId(xbody.BlockId, parent.BlockId)) {
+ assert(!found);
+ found = true;
+ worklist.push({body: xbody, ppoint: parent.Index,
+ gcInfo: gcInfo, why: entry});
+ }
+ }
+ assert(found);
+ }
+ }
+
+ // Also propagate to the *end* of this loop, for the previous
+ // iteration.
+ worklist.push({body: body, ppoint: body.Index[1],
+ gcInfo: gcInfo, why: entry});
+ } else if (variable.Kind == "Arg" && gcInfo) {
+ // The scope of arguments starts at the beginning of the
+ // function
+ return entry;
+ } else if (entry.preGCLive) {
+ // We didn't find a "good" explanation beginning of the live
+ // range, but we do know the variable was live across the GC.
+ // This can happen if the live range started when a variable is
+ // used as a retparam.
+ return entry;
+ }
+ }
+
+ var predecessors = getPredecessors(body);
+ if (!(ppoint in predecessors))
+ continue;
+
+ for (var edge of predecessors[ppoint]) {
+ var source = edge.Index[0];
+
+ var edge_kills = edgeKillsVariable(edge, variable);
+ var edge_uses = edgeUsesVariable(edge, variable, body);
+
+ if (edge_kills || edge_uses) {
+ if (!body.minimumUse || source < body.minimumUse)
+ body.minimumUse = source;
+ }
+
+ if (edge_kills) {
+ // This is a beginning of the variable's live range. If we can
+ // reach a GC call from here, then we're done -- we have a path
+ // from the beginning of the live range, through the GC call,
+ // to a use after the GC call that proves its live range
+ // extends at least that far.
+ if (gcInfo)
+ return {body: body, ppoint: source, gcInfo: gcInfo, why: entry };
+
+ // Otherwise, keep searching through the graph, but truncate
+ // this particular branch of the search at this edge.
+ continue;
+ }
+
+ var src_gcInfo = gcInfo;
+ var src_preGCLive = preGCLive;
+ if (!gcInfo && !(source in body.suppressed) && !suppressed) {
+ var gcName = edgeCanGC(edge, body);
+ if (gcName)
+ src_gcInfo = {name:gcName, body:body, ppoint:source};
+ }
+
+ if (edge_uses) {
+ // The live range starts at least this far back, so we're done
+ // for the same reason as with edge_kills. The only difference
+ // is that a GC on this edge indicates a hazard, whereas if
+ // we're killing a live range in the GC call then it's not live
+ // *across* the call.
+ //
+ // However, we may want to generate a longer usage chain for
+ // the variable than is minimally necessary. For example,
+ // consider:
+ //
+ // Value v = f();
+ // if (v.isUndefined())
+ // return false;
+ // gc();
+ // return v;
+ //
+ // The call to .isUndefined() is considered to be a use and
+ // therefore indicates that v must be live at that point. But
+ // it's more helpful to the user to continue the 'why' path to
+ // include the ancestor where the value was generated. So we
+ // will only return here if edge.Kind is Assign; otherwise,
+ // we'll pass a "preGCLive" value up through the worklist to
+ // remember that the variable *is* alive before the GC and so
+ // this function should be returning a true value even if we
+ // don't find an assignment.
+
+ if (src_gcInfo) {
+ src_preGCLive = true;
+ if (edge.Kind == 'Assign')
+ return {body:body, ppoint:source, gcInfo:src_gcInfo, why:entry};
+ }
+ }
+
+ if (edge.Kind == "Loop") {
+ // Additionally propagate the search into a loop body, starting
+ // with the exit point.
+ var found = false;
+ for (var xbody of functionBodies) {
+ if (sameBlockId(xbody.BlockId, edge.BlockId)) {
+ assert(!found);
+ found = true;
+ worklist.push({body:xbody, ppoint:xbody.Index[1],
+ preGCLive: src_preGCLive, gcInfo:src_gcInfo,
+ why:entry});
+ }
+ }
+ assert(found);
+ // Don't continue to predecessors here without going through
+ // the loop. (The points in this body that enter the loop will
+ // be traversed when we reach the entry point of the loop.)
+ break;
+ }
+
+ // Propagate the search to the predecessors of this edge.
+ worklist.push({body:body, ppoint:source,
+ preGCLive: src_preGCLive, gcInfo:src_gcInfo,
+ why:entry});
+ }
+ }
+
+ return null;
+}
+
+function variableLiveAcrossGC(suppressed, variable)
+{
+ // A variable is live across a GC if (1) it is used by an edge (as in, it
+ // was at least initialized), and (2) it is used after a GC in a successor
+ // edge.
+
+ for (var body of functionBodies)
+ body.minimumUse = 0;
+
+ for (var body of functionBodies) {
+ if (!("PEdge" in body))
+ continue;
+ for (var edge of body.PEdge) {
+ // Examples:
+ //
+ // JSObject* obj = NewObject();
+ // cangc();
+ // obj = NewObject(); <-- mentions 'obj' but kills previous value
+ //
+ // This is not a hazard. Contrast this with:
+ //
+ // JSObject* obj = NewObject();
+ // cangc();
+ // obj = LookAt(obj); <-- uses 'obj' and kills previous value
+ //
+ // This is a hazard; the initial value of obj is live across
+ // cangc(). And a third possibility:
+ //
+ // JSObject* obj = NewObject();
+ // obj = CopyObject(obj);
+ //
+ // This is not a hazard, because even though CopyObject can GC, obj
+ // is not live across it. (obj is live before CopyObject, and
+ // probably after, but not across.) There may be a hazard within
+ // CopyObject, of course.
+ //
+
+ var usePoint = edgeUsesVariable(edge, variable, body);
+ if (usePoint) {
+ var call = findGCBeforeValueUse(body, usePoint, suppressed, variable);
+ if (!call)
+ continue;
+
+ call.afterGCUse = usePoint;
+ return call;
+ }
+ }
+ }
+ return null;
+}
+
+// An unrooted variable has its address stored in another variable via
+// assignment, or passed into a function that can GC. If the address is
+// assigned into some other variable, we can't track it to see if it is held
+// live across a GC. If it is passed into a function that can GC, then it's
+// sort of like a Handle to an unrooted location, and the callee could GC
+// before overwriting it or rooting it.
+function unsafeVariableAddressTaken(suppressed, variable)
+{
+ for (var body of functionBodies) {
+ if (!("PEdge" in body))
+ continue;
+ for (var edge of body.PEdge) {
+ if (edgeTakesVariableAddress(edge, variable, body)) {
+ if (edge.Kind == "Assign" || (!suppressed && edgeCanGC(edge)))
+ return {body:body, ppoint:edge.Index[0]};
+ }
+ }
+ }
+ return null;
+}
+
+// Read out the brief (non-JSON, semi-human-readable) CFG description for the
+// given function and store it.
+function loadPrintedLines(functionName)
+{
+ assert(!os.system("xdbfind src_body.xdb '" + functionName + "' > " + tmpfile));
+ var lines = snarf(tmpfile).split('\n');
+
+ for (var body of functionBodies)
+ body.lines = [];
+
+ // Distribute lines of output to the block they originate from.
+ var currentBody = null;
+ for (var line of lines) {
+ if (/^block:/.test(line)) {
+ if (match = /:(loop#[\d#]+)/.exec(line)) {
+ var loop = match[1];
+ var found = false;
+ for (var body of functionBodies) {
+ if (body.BlockId.Kind == "Loop" && body.BlockId.Loop == loop) {
+ assert(!found);
+ found = true;
+ currentBody = body;
+ }
+ }
+ assert(found);
+ } else {
+ for (var body of functionBodies) {
+ if (body.BlockId.Kind == "Function")
+ currentBody = body;
+ }
+ }
+ }
+ if (currentBody)
+ currentBody.lines.push(line);
+ }
+}
+
+function findLocation(body, ppoint, opts={brief: false})
+{
+ var location = body.PPoint[ppoint - 1].Location;
+ var file = location.CacheString;
+
+ if (file.indexOf(sourceRoot) == 0)
+ file = file.substring(sourceRoot.length);
+
+ if (opts.brief) {
+ var m = /.*\/(.*)/.exec(file);
+ if (m)
+ file = m[1];
+ }
+
+ return file + ":" + location.Line;
+}
+
+function locationLine(text)
+{
+ if (match = /:(\d+)$/.exec(text))
+ return match[1];
+ return 0;
+}
+
+function printEntryTrace(functionName, entry)
+{
+ var gcPoint = entry.gcInfo ? entry.gcInfo.ppoint : 0;
+
+ if (!functionBodies[0].lines)
+ loadPrintedLines(functionName);
+
+ while (entry) {
+ var ppoint = entry.ppoint;
+ var lineText = findLocation(entry.body, ppoint, {"brief": true});
+
+ var edgeText = "";
+ if (entry.why && entry.why.body == entry.body) {
+ // If the next point in the trace is in the same block, look for an edge between them.
+ var next = entry.why.ppoint;
+
+ if (!entry.body.edgeTable) {
+ var table = {};
+ entry.body.edgeTable = table;
+ for (var line of entry.body.lines) {
+ if (match = /^\w+\((\d+,\d+),/.exec(line))
+ table[match[1]] = line; // May be multiple?
+ }
+ if (entry.body.BlockId.Kind == 'Loop') {
+ const [startPoint, endPoint] = entry.body.Index;
+ table[`${endPoint},${startPoint}`] = '(loop to next iteration)';
+ }
+ }
+
+ edgeText = entry.body.edgeTable[ppoint + "," + next];
+ assert(edgeText);
+ if (ppoint == gcPoint)
+ edgeText += " [[GC call]]";
+ } else {
+ // Look for any outgoing edge from the chosen point.
+ for (var line of entry.body.lines) {
+ if (match = /\((\d+),/.exec(line)) {
+ if (match[1] == ppoint) {
+ edgeText = line;
+ break;
+ }
+ }
+ }
+ if (ppoint == entry.body.Index[1] && entry.body.BlockId.Kind == "Function")
+ edgeText += " [[end of function]]";
+ }
+
+ print(" " + lineText + (edgeText.length ? ": " + edgeText : ""));
+ entry = entry.why;
+ }
+}
+
+function isRootedType(type)
+{
+ return type.Kind == "CSU" && isRootedTypeName(type.Name);
+}
+
+function typeDesc(type)
+{
+ if (type.Kind == "CSU") {
+ return type.Name;
+ } else if ('Type' in type) {
+ var inner = typeDesc(type.Type);
+ if (type.Kind == 'Pointer')
+ return inner + '*';
+ else if (type.Kind == 'Array')
+ return inner + '[]';
+ else
+ return inner + '?';
+ } else {
+ return '???';
+ }
+}
+
+function processBodies(functionName)
+{
+ if (!("DefineVariable" in functionBodies[0]))
+ return;
+ var suppressed = (mangled(functionName) in suppressedFunctions);
+ for (var variable of functionBodies[0].DefineVariable) {
+ var name;
+ if (variable.Variable.Kind == "This")
+ name = "this";
+ else if (variable.Variable.Kind == "Return")
+ name = "<returnvalue>";
+ else
+ name = variable.Variable.Name[0];
+
+ if (isRootedType(variable.Type)) {
+ if (!variableLiveAcrossGC(suppressed, variable.Variable)) {
+ // The earliest use of the variable should be its constructor.
+ var lineText;
+ for (var body of functionBodies) {
+ if (body.minimumUse) {
+ var text = findLocation(body, body.minimumUse);
+ if (!lineText || locationLine(lineText) > locationLine(text))
+ lineText = text;
+ }
+ }
+ print("\nFunction '" + functionName + "'" +
+ " has unnecessary root '" + name + "' at " + lineText);
+ }
+ } else if (isUnrootedType(variable.Type)) {
+ var result = variableLiveAcrossGC(suppressed, variable.Variable);
+ if (result) {
+ var lineText = findLocation(result.gcInfo.body, result.gcInfo.ppoint);
+ print("\nFunction '" + functionName + "'" +
+ " has unrooted '" + name + "'" +
+ " of type '" + typeDesc(variable.Type) + "'" +
+ " live across GC call " + result.gcInfo.name +
+ " at " + lineText);
+ printEntryTrace(functionName, result);
+ }
+ result = unsafeVariableAddressTaken(suppressed, variable.Variable);
+ if (result) {
+ var lineText = findLocation(result.body, result.ppoint);
+ print("\nFunction '" + functionName + "'" +
+ " takes unsafe address of unrooted '" + name + "'" +
+ " at " + lineText);
+ printEntryTrace(functionName, {body:result.body, ppoint:result.ppoint});
+ }
+ }
+ }
+}
+
+if (batch == 1)
+ print("Time: " + new Date);
+
+var xdb = xdbLibrary();
+xdb.open("src_body.xdb");
+
+var minStream = xdb.min_data_stream()|0;
+var maxStream = xdb.max_data_stream()|0;
+
+var N = (maxStream - minStream) + 1;
+var start = Math.floor((batch - 1) / numBatches * N) + minStream;
+var start_next = Math.floor(batch / numBatches * N) + minStream;
+var end = start_next - 1;
+
+function process(name, json) {
+ functionName = name;
+ functionBodies = JSON.parse(json);
+
+ for (var body of functionBodies)
+ body.suppressed = [];
+ for (var body of functionBodies) {
+ for (var [pbody, id] of allRAIIGuardedCallPoints(functionBodies, body, isSuppressConstructor))
+ pbody.suppressed[id] = true;
+ }
+ processBodies(functionName);
+}
+
+if (theFunctionNameToFind) {
+ var data = xdb.read_entry(theFunctionNameToFind);
+ var json = data.readString();
+ process(theFunctionNameToFind, json);
+ xdb.free_string(data);
+ quit(0);
+}
+
+for (var nameIndex = start; nameIndex <= end; nameIndex++) {
+ var name = xdb.read_key(nameIndex);
+ var functionName = name.readString();
+ var data = xdb.read_entry(name);
+ xdb.free_string(name);
+ var json = data.readString();
+ try {
+ process(functionName, json);
+ } catch (e) {
+ printErr("Exception caught while handling " + functionName);
+ throw(e);
+ }
+ xdb.free_string(data);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-21 03:27:07 +0000