ladybird/Userland/Libraries/LibJS/Runtime/Error.h
Andreas Kling 3c74dc9f4d LibJS: Segregate GC-allocated objects by type
This patch adds two macros to declare per-type allocators:

- JS_DECLARE_ALLOCATOR(TypeName)
- JS_DEFINE_ALLOCATOR(TypeName)

When used, they add a type-specific CellAllocator that the Heap will
delegate allocation requests to.

The result of this is that GC objects of the same type always end up
within the same HeapBlock, drastically reducing the ability to perform
type confusion attacks.

It also improves HeapBlock utilization, since each block now has cells
sized exactly to the type used within that block. (Previously we only
had a handful of block sizes available, and most GC allocations ended
up with a large amount of slack in their tails.)

There is a small performance hit from this, but I'm sure we can make
up for it elsewhere.

Note that the old size-based allocators still exist, and we fall back
to them for any type that doesn't have its own CellAllocator.
2023-11-19 12:10:31 +01:00

76 lines
2.7 KiB
C++

/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021-2022, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/DeprecatedFlyString.h>
#include <AK/String.h>
#include <LibJS/Runtime/Completion.h>
#include <LibJS/Runtime/Object.h>
#include <LibJS/SourceRange.h>
namespace JS {
struct TracebackFrame {
DeprecatedFlyString function_name;
[[nodiscard]] SourceRange const& source_range() const;
mutable Variant<SourceRange, UnrealizedSourceRange> source_range_storage;
};
enum CompactTraceback {
No,
Yes,
};
class Error : public Object {
JS_OBJECT(Error, Object);
JS_DECLARE_ALLOCATOR(Error);
public:
static NonnullGCPtr<Error> create(Realm&);
static NonnullGCPtr<Error> create(Realm&, String message);
static NonnullGCPtr<Error> create(Realm&, StringView message);
virtual ~Error() override = default;
[[nodiscard]] String stack_string(CompactTraceback compact = CompactTraceback::No) const;
ThrowCompletionOr<void> install_error_cause(Value options);
Vector<TracebackFrame, 32> const& traceback() const { return m_traceback; }
protected:
explicit Error(Object& prototype);
private:
void populate_stack();
Vector<TracebackFrame, 32> m_traceback;
};
// NOTE: Making these inherit from Error is not required by the spec but
// our way of implementing the [[ErrorData]] internal slot, which is
// used in Object.prototype.toString().
#define DECLARE_NATIVE_ERROR(ClassName, snake_name, PrototypeName, ConstructorName) \
class ClassName final : public Error { \
JS_OBJECT(ClassName, Error); \
JS_DECLARE_ALLOCATOR(ClassName); \
\
public: \
static NonnullGCPtr<ClassName> create(Realm&); \
static NonnullGCPtr<ClassName> create(Realm&, String message); \
static NonnullGCPtr<ClassName> create(Realm&, StringView message); \
\
explicit ClassName(Object& prototype); \
virtual ~ClassName() override = default; \
};
#define __JS_ENUMERATE(ClassName, snake_name, PrototypeName, ConstructorName, ArrayType) \
DECLARE_NATIVE_ERROR(ClassName, snake_name, PrototypeName, ConstructorName)
JS_ENUMERATE_NATIVE_ERRORS
#undef __JS_ENUMERATE
}