llvm/llvm/include/llvm/Transforms/Utils/SymbolRewriter.h

//===- SymbolRewriter.h - Symbol Rewriting Pass -----------------*- C++ -*-===//
//
// 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 provides the prototypes and definitions related to the Symbol
// Rewriter pass.
//
// The Symbol Rewriter pass takes a set of rewrite descriptors which define
// transformations for symbol names.  These can be either single name to name
// trnsformation or more broad regular expression based transformations.
//
// All the functions are re-written at the IR level.  The Symbol Rewriter itself
// is exposed as a module level pass.  All symbols at the module level are
// iterated.  For any matching symbol, the requested transformation is applied,
// updating references to it as well (a la RAUW).  The resulting binary will
// only contain the rewritten symbols.
//
// By performing this operation in the compiler, we are able to catch symbols
// that would otherwise not be possible to catch (e.g. inlined symbols).
//
// This makes it possible to cleanly transform symbols without resorting to
// overly-complex macro tricks and the pre-processor.  An example of where this
// is useful is the sanitizers where we would like to intercept a well-defined
// set of functions across the module.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_TRANSFORMS_UTILS_SYMBOLREWRITER_H
#define LLVM_TRANSFORMS_UTILS_SYMBOLREWRITER_H

#include "llvm/IR/PassManager.h"
#include <list>
#include <memory>
#include <string>

namespace llvm {

class MemoryBuffer;
class Module;

namespace yaml {

class KeyValueNode;
class MappingNode;
class ScalarNode;
class Stream;

} // end namespace yaml

namespace SymbolRewriter {

/// The basic entity representing a rewrite operation.  It serves as the base
/// class for any rewrite descriptor.  It has a certain set of specializations
/// which describe a particular rewrite.
///
/// The RewriteMapParser can be used to parse a mapping file that provides the
/// mapping for rewriting the symbols.  The descriptors individually describe
/// whether to rewrite a function, global variable, or global alias.  Each of
/// these can be selected either by explicitly providing a name for the ones to
/// be rewritten or providing a (posix compatible) regular expression that will
/// select the symbols to rewrite.  This descriptor list is passed to the
/// SymbolRewriter pass.
class RewriteDescriptor { … };

RewriteDescriptorList;

class RewriteMapParser { … };

} // end namespace SymbolRewriter

class RewriteSymbolPass : public PassInfoMixin<RewriteSymbolPass> { … };

} // end namespace llvm

#endif // LLVM_TRANSFORMS_UTILS_SYMBOLREWRITER_H