gecko-dev/xpcom/analysis/stack.js

200 строки
5.1 KiB
JavaScript

include("gcc_util.js");
include("unstable/lazy_types.js");
function process_type(c)
{
if ((c.kind == 'class' || c.kind == 'struct') &&
!c.isIncomplete)
isStack(c);
}
/**
* A BlameChain records a chain of one or more location/message pairs. It
* can be used to issue a complex error message such as:
* location: error: Allocated class Foo on the heap
* locationofFoo: class Foo inherits from class Bar
* locationofBar: in class Bar
* locationofBarMem: Member Bar::mFoo
* locationofBaz: class Baz is annotated NS_STACK
*/
function BlameChain(loc, message, prev)
{
this.loc = loc;
this.message = message;
this.prev = prev;
}
BlameChain.prototype.toString = function()
{
let loc = this.loc;
if (loc === undefined)
loc = "<unknown location>";
let str = '%s: %s'.format(loc.toString(), this.message);
if (this.prev)
str += "\n%s".format(this.prev);
return str;
};
function isStack(c)
{
function calculate()
{
if (hasAttribute(c, 'NS_stack'))
return new BlameChain(c.loc, '%s %s is annotated NS_STACK_CLASS'.format(c.kind, c.name));
for each (let base in c.bases) {
let r = isStack(base.type);
if (r != null)
return new BlameChain(c.loc, '%s %s is a base of %s %s'.format(base.type.kind, base.type.name, c.kind, c.name), r);
}
for each (let member in c.members) {
if (member.isFunction)
continue;
if (hasAttribute(member, 'NS_okonheap'))
continue;
let type = member.type;
while (true) {
if (type === undefined)
break;
if (type.isArray) {
type = type.type;
continue;
}
if (type.typedef) {
if (hasAttribute(type, 'NS_stack'))
return true;
type = type.typedef;
continue;
}
break;
}
if (type === undefined) {
warning("incomplete type for member " + member + ".", member.loc);
continue;
}
if (type.isPointer || type.isReference)
continue;
if (!type.kind || (type.kind != 'class' && type.kind != 'struct'))
continue;
let r = isStack(type);
if (r != null)
return new BlameChain(c.loc, 'In class %s'.format(c.name),
new BlameChain(member.loc, 'Member %s'.format(member.name), r));
}
return null;
}
if (c.isIncomplete)
throw Error("Can't get stack property for incomplete type.");
if (!c.hasOwnProperty('isStack'))
c.isStack = calculate();
return c.isStack;
}
function isVoidPtr(t)
{
return t.isPointer && t.type.name == 'void';
}
function xrange(start, end, skip)
{
for (;
(skip > 0) ? (start < end) : (start > end);
start += skip)
yield start;
}
function process_cp_pre_genericize(fndecl)
{
function findconstructors(t, stack)
{
function getLocation() {
let loc = location_of(t);
if (loc !== undefined)
return loc;
for (let i = stack.length - 1; i >= 0; --i) {
loc = location_of(stack[i]);
if (loc !== undefined)
return loc;
}
return location_of(DECL_SAVED_TREE(fndecl));
}
try {
t.tree_check(CALL_EXPR);
let fncall =
callable_arg_function_decl(CALL_EXPR_FN(t));
if (fncall == null)
return;
let nameid = DECL_NAME(fncall);
if (IDENTIFIER_OPNAME_P(nameid)) {
let name = IDENTIFIER_POINTER(nameid);
if (name == "operator new" || name == "operator new []") {
let fncallobj = dehydra_convert(TREE_TYPE(fncall));
if (fncallobj.parameters.length == 2 &&
isVoidPtr(fncallobj.parameters[1]))
return;
let i;
for (i in xrange(stack.length - 1, -1, -1)) {
if (TREE_CODE(stack[i]) != NOP_EXPR)
break;
}
let assign = stack[i];
switch (TREE_CODE(assign)) {
case VAR_DECL:
break;
case INIT_EXPR:
case MODIFY_EXPR:
case TARGET_EXPR:
assign = assign.operands()[1];
break;
case CALL_EXPR:
case AGGR_INIT_EXPR:
assign = stack[i + 1];
break;
default:
error("Unrecognized assignment from operator new: %s. Tree code stack: %s".format(TREE_CODE(assign), [TREE_CODE(s) for each (s in stack)].join(",")), getLocation());
return;
}
let destType = dehydra_convert(TREE_TYPE(assign));
if (!destType.isPointer && !destType.isReference) {
error("operator new not assigned to pointer/ref?", getLocation());
return;
}
destType = destType.type;
let r = isStack(destType);
if (r)
warning("constructed object of type '%s' not on the stack: %s".format(destType.name, r), getLocation());
}
}
}
catch (e if e.TreeCheckError) { }
}
if (hasAttribute(dehydra_convert(fndecl), 'NS_suppress_stackcheck'))
return;
walk_tree(DECL_SAVED_TREE(fndecl), findconstructors);
}