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diff --git a/clang-r353983e/include/llvm/Transforms/Utils/SymbolRewriter.h b/clang-r353983e/include/llvm/Transforms/Utils/SymbolRewriter.h
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+//===- 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;
+class ModulePass;
+
+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 {
+public:
+  enum class Type {
+    Invalid,        /// invalid
+    Function,       /// function - descriptor rewrites a function
+    GlobalVariable, /// global variable - descriptor rewrites a global variable
+    NamedAlias,     /// named alias - descriptor rewrites a global alias
+  };
+
+  RewriteDescriptor(const RewriteDescriptor &) = delete;
+  RewriteDescriptor &operator=(const RewriteDescriptor &) = delete;
+  virtual ~RewriteDescriptor() = default;
+
+  Type getType() const { return Kind; }
+
+  virtual bool performOnModule(Module &M) = 0;
+
+protected:
+  explicit RewriteDescriptor(Type T) : Kind(T) {}
+
+private:
+  const Type Kind;
+};
+
+using RewriteDescriptorList = std::list<std::unique_ptr<RewriteDescriptor>>;
+
+class RewriteMapParser {
+public:
+  bool parse(const std::string &MapFile, RewriteDescriptorList *Descriptors);
+
+private:
+  bool parse(std::unique_ptr<MemoryBuffer> &MapFile, RewriteDescriptorList *DL);
+  bool parseEntry(yaml::Stream &Stream, yaml::KeyValueNode &Entry,
+                  RewriteDescriptorList *DL);
+  bool parseRewriteFunctionDescriptor(yaml::Stream &Stream,
+                                      yaml::ScalarNode *Key,
+                                      yaml::MappingNode *Value,
+                                      RewriteDescriptorList *DL);
+  bool parseRewriteGlobalVariableDescriptor(yaml::Stream &Stream,
+                                            yaml::ScalarNode *Key,
+                                            yaml::MappingNode *Value,
+                                            RewriteDescriptorList *DL);
+  bool parseRewriteGlobalAliasDescriptor(yaml::Stream &YS, yaml::ScalarNode *K,
+                                         yaml::MappingNode *V,
+                                         RewriteDescriptorList *DL);
+};
+
+} // end namespace SymbolRewriter
+
+ModulePass *createRewriteSymbolsPass();
+ModulePass *createRewriteSymbolsPass(SymbolRewriter::RewriteDescriptorList &);
+
+class RewriteSymbolPass : public PassInfoMixin<RewriteSymbolPass> {
+public:
+  RewriteSymbolPass() { loadAndParseMapFiles(); }
+
+  RewriteSymbolPass(SymbolRewriter::RewriteDescriptorList &DL) {
+    Descriptors.splice(Descriptors.begin(), DL);
+  }
+
+  PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM);
+
+  // Glue for old PM
+  bool runImpl(Module &M);
+
+private:
+  void loadAndParseMapFiles();
+
+  SymbolRewriter::RewriteDescriptorList Descriptors;
+};
+
+} // end namespace llvm
+
+#endif //LLVM_TRANSFORMS_UTILS_SYMBOLREWRITER_H