llvm/clang/lib/AST/Randstruct.cpp

//===--- Randstruct.cpp ---------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains the implementation for Clang's structure field layout
// randomization.
//
//===----------------------------------------------------------------------===//

#include "clang/AST/Randstruct.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTDiagnostic.h"
#include "clang/AST/Attr.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h" // For StaticAssertDecl
#include "clang/Basic/Diagnostic.h"
#include "llvm/ADT/SmallVector.h"

#include <algorithm>
#include <random>
#include <set>
#include <sstream>
#include <string>

ASTContext;
FieldDecl;
SmallVector;

namespace {

// FIXME: Replace this with some discovery once that mechanism exists.
enum { … };

// The Bucket class holds the struct fields we're trying to fill to a
// cache-line.
class Bucket { … };

void Bucket::addField(FieldDecl *Field, int FieldSize) { … }

struct BitfieldRunBucket : public Bucket { … };

void randomizeStructureLayoutImpl(const ASTContext &Context,
                                  llvm::SmallVectorImpl<FieldDecl *> &FieldsOut,
                                  std::mt19937 &RNG) { … }

} // anonymous namespace

namespace clang {
namespace randstruct {

bool randomizeStructureLayout(const ASTContext &Context, RecordDecl *RD,
                              SmallVectorImpl<Decl *> &FinalOrdering) { … }

} // end namespace randstruct
} // end namespace clang