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    <p>Hi Rafael,</p>
    <p>I did read into clang-refactor a while ago but unfortunatly could
      not follow that up. If I recall correctly its about
      source-to-source transformation (as you said) and aims at
      implementing the primitive refactorings that exist (e.g.
      extract-method, extract-variable, ....).</p>
    <p>Rewriting itself should happen with the normal tooling framework.<br>
    </p>
    (<a class="moz-txt-link-freetext" href="https://clang.llvm.org/docs/RefactoringEngine.html">https://clang.llvm.org/docs/RefactoringEngine.html</a>)<br>
    <br>
    Maybe the implementers of the existing code can give better comments
    on you proposal (and might have considered a similar solution to
    yours already). <br>
    <br>
    +Alex Lorenz<br>
    <br>
    All the best, Jonas<br>
    <br>
    <br>
    <div class="moz-cite-prefix">Am 17.07.2018 um 14:46 schrieb
      Rafael·Stahl:<br>
    </div>
    <blockquote type="cite"
      cite="mid:f94cfa5f-233e-7cad-bd6e-09ce07a549bc@tum.de">
      <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
      <p>Hi Jonas</p>
      <p>Thanks for introducing me to this, I have seen the
        "Replacement" before, but not clang-refactor.</p>
      <p>However it seems to only provide management facilities around
        rewrite operations and not aid with the rewriting itself. Am I
        missing something here?</p>
      <p>The two core problems for me:</p>
      <p>- nesting replacements: When implementing replacements with
        clang-refactor, I still have to provide replacements that are
        closed in themselves. I cannot make them depend on others,
        right?<br>
        - macros: clang-refactor only seems to work with spelling
        locations.</p>
      <p>Maybe an even simpler example: Replace all additions with
        "add(lhs, rhs)". This in itself is very difficult with clang as
        soon as the Stmts are nested or macros are involved.<br>
      </p>
      <p>Best regards<br>
        Rafael<br>
      </p>
      <br>
      <div class="moz-cite-prefix">On 16.07.2018 19:06, Jonas Toth via
        cfe-dev wrote:<br>
      </div>
      <blockquote type="cite"
        cite="mid:cef03437-19d3-fba7-82d9-2a7983011ddc@jonas-toth.eu">
        <meta http-equiv="Content-Type" content="text/html;
          charset=utf-8">
        <p>Hi Rafael,</p>
        <p>wouldn't your usecase be a task for clang-refactor?</p>
        <p>Best,  Jonas<br>
        </p>
        <br>
        <div class="moz-cite-prefix">Am 16.07.2018 um 17:08 schrieb
          Rafael·Stahl via cfe-dev:<br>
        </div>
        <blockquote type="cite"
          cite="mid:78dd3056-9faa-4dae-5bf8-9d10f3a3219d@tum.de">Hey
          everyone <br>
          <br>
          The rewriting API of Clang operates on the source code in
          textual form. The user can use AST nodes to figure out what to
          replace, but in the end he has to remove and insert snippets
          in a linear piece of text. <br>
          <br>
          This is very inconvenient when it is required to restructure
          and nest replacements. The involvement of macros makes a
          manual process even more difficult. See some recent threads
          expressing difficulty with the API [1][2]. <br>
          <br>
          What do I mean by "nested replacements"? For example in the
          following: <br>
          <br>
              int i = x + s->a; <br>
          <br>
          I would want to replace the BinaryOperator with a function
          call and the MemberExpr with some constant: <br>
          <br>
              int i = Addition(x, 7); <br>
          <br>
          When keeping the two replacement rules independent of each
          other, achieving this with the current API is extremely
          difficult. More so when macros are involved. <br>
          <br>
          I am proposing some kind of helper that aims to solve these
          issues by providing an interface that offers to directly
          replace AST nodes and a mechanism to nest AST node
          replacements - without having to worry about macros. <br>
          <br>
          Potential usage: <br>
          <br>
          - Develop a class that derives from StmtToRewrite to define
          how replacements should happen: <br>
          <br>
              class RewriteAdds : public cu::StmtToRewrite <br>
              { <br>
              public: <br>
                  std::string makeReplaceStr() const override <br>
                  { <br>
                      auto binOp =
          dyn_cast<BinaryOperator>(replaceS); <br>
                      return "Addition(" +
          getMgr()->getReplaced(binOp->getLHS()).strToInsert + ",
          " + <br>
          getMgr()->getReplaced(binOp->getRHS()).strToInsert +
          ")"; <br>
                  } <br>
              }; <br>
          <br>
              class RewriteMembs : public cu::StmtToRewrite <br>
              { <br>
              public: <br>
                  std::string makeReplaceStr() const override <br>
                  { <br>
                      return "7"; <br>
                  } <br>
              }; <br>
          <br>
          - Construct a RewriteManager: <br>
          <br>
              cu::RewriteManager mgr(ACtx, PP); <br>
          <br>
          - Add rewriting operations to the manager: <br>
          <br>
              // std::vector<const Stmt *> AddStmts = /* matched
          from binaryOperator() with plus */ <br>
              // std::vector<const Stmt *> MembStmts = /* matched
          from memberExpr() */ <br>
              for (const auto &S : AddStmts)
          mgr.registerStmt<RewriteAdds>(S); <br>
              for (const auto &S : MembStmts)
          mgr.registerStmt<RewriteMembs>(S); <br>
          <br>
          - Retrieve and apply the results: <br>
          <br>
              clang::Rewriter rewriter(SM, LangOpts); <br>
              for (const auto &r : mgr.getReplacements()) { <br>
                  rewriter.RemoveText(r.rangeToRemove); <br>
                  rewriter.InsertText(r.rangeToRemove.getBegin(),
          r.strToInsert); <br>
              } <br>
          <br>
          <br>
          At the end of this mail is my low quality code that kind-of
          implements this. TLDR: <br>
          <br>
          - Build a hierarchy of stmts to replace and keep track of
          which replacements must be combined <br>
          - Move further up in the AST if these replacements are inside
          a macro <br>
          - Recursively lex the file and look for replacements
          outside-in by spelling locations. Expand any macros that are
          encountered during this. The re-lexing idea is based on the
          hint in [3]. <br>
          <br>
          The code has the following shortcomings: <br>
          <br>
          - I do not know how to distinguish macro argument expansions
          within macros. For example in "#define FOO(a) a + a" the two
          "a"s expand to different AST nodes that could be replaced with
          different rules. This is an important issue, because it can
          lead to completely broken code with nesting. <br>
          - Limited to Stmts, when Decls should be supported too. <br>
          - Very un-optimized with lexing the entire source file many
          times. Easy to solve, but didn't want to raise the complexity
          further for now. <br>
          - Could keep written code more clean by only expanding macros
          if required. For example not required if just a macro arg is
          replaced and all expansions would be the same. <br>
          <br>
          <br>
          I am very interested in your general thoughts. I'm not very
          experienced with clang, but this was my vision how I would
          want to do replacements. Are you interested in getting this
          into clang? I would need help with ironing out the remaining
          issues. <br>
          <br>
          -Rafael <br>
          <br>
          <br>
          [1] <a class="moz-txt-link-freetext"
            href="http://lists.llvm.org/pipermail/cfe-dev/2018-July/058430.html"
            moz-do-not-send="true">http://lists.llvm.org/pipermail/cfe-dev/2018-July/058430.html</a>
          <br>
          [2] <a class="moz-txt-link-freetext"
            href="http://lists.llvm.org/pipermail/cfe-dev/2018-June/058213.html"
            moz-do-not-send="true">http://lists.llvm.org/pipermail/cfe-dev/2018-June/058213.html</a>
          <br>
          [3] <a class="moz-txt-link-freetext"
            href="http://lists.llvm.org/pipermail/cfe-dev/2017-August/055079.html"
            moz-do-not-send="true">http://lists.llvm.org/pipermail/cfe-dev/2017-August/055079.html</a>
          <br>
          <br>
          <br>
          <br>
          ---------------------------------------- <br>
          <br>
          RewriteManager.h <br>
          <br>
          ---------------------------------------- <br>
          <br>
          #ifndef CLANGUTIL_REWRITEMANAGER_H <br>
          #define CLANGUTIL_REWRITEMANAGER_H <br>
          <br>
          #include "ClangUtil/SourceRangeLess.h" <br>
          #include "make_unique.h" <br>
          #include "clang/AST/AST.h" <br>
          #include <vector> <br>
          #include <map> <br>
          <br>
          <br>
          // TODO extend to decls <br>
          <br>
          <br>
          namespace cu <br>
          { <br>
          // Represents a statement in the original AST that should be
          rewritten. To implement recursive replacements, call <br>
          // getMgr()->getReplaced() on any AST node within the
          makeReplaceStr callback. <br>
          class StmtToRewrite <br>
          { <br>
              friend class RewriteManager; <br>
          <br>
          public: <br>
              // Returns the enclosing RewriteManager. <br>
              class RewriteManager *getMgr() const; <br>
              // Override this to build a replacement string. Implement
          recursive replacements with RewriteManager::getReplaced. <br>
              virtual std::string makeReplaceStr() const = 0; <br>
          <br>
              // The statement to replace. <br>
              const clang::Stmt *replaceS = nullptr; <br>
          <br>
          private: <br>
              RewriteManager *m_mgr; <br>
          }; <br>
          <br>
          struct RewriteOperation <br>
          { <br>
              clang::SourceRange rangeToRemove; <br>
              std::string strToInsert; <br>
          }; <br>
          <br>
          // A class for managing replacements of AST nodes. It allows
          to specifically target AST nodes instead of raw source <br>
          // locations to enable easy replacements involving macros and
          nested replacements. <br>
          // For extended documentation see: doc/rewriting.md <br>
          class RewriteManager <br>
          { <br>
          public: <br>
              RewriteManager(clang::ASTContext &ACtx,
          clang::Preprocessor &PP); <br>
          <br>
              clang::ASTContext &getACtx() const { return ACtx; } <br>
          <br>
              // Registers a StmtToRewrite for use with getReplacements.
          Call this on all <br>
              // statements that should be rewritten before calling any
          rewriting functions. <br>
              void registerStmt(std::unique_ptr<StmtToRewrite> S);
          <br>
          <br>
              // Helper for constructing the custom type from a Stmt. <br>
              template <typename T, typename... Args> <br>
              void registerStmt(const clang::Stmt *S, Args... args) <br>
              { <br>
                  auto p =
          std::make_unique<T>(std::forward<Args>(args)...);
          <br>
                  p->replaceS = S; <br>
                  registerStmt(std::move(p)); <br>
              } <br>
          <br>
              // Get the full replacement of an AST node. Note that this
          function removes any replaced statements from the work <br>
              // list, so calling it twice will only replace the first
          time. <br>
              RewriteOperation getReplaced(const clang::Stmt *S); <br>
              // Get all replacements. These may be fewer than the
          requested ones because of nesting. <br>
              std::vector<RewriteOperation> getReplacements(); <br>
          <br>
          private: <br>
              std::string getExpandedCode(const clang::Stmt
          *toReplaceS); <br>
          <br>
          private: <br>
              clang::ASTContext &ACtx; <br>
              const clang::LangOptions &LangOpts; <br>
              clang::SourceManager &SM; <br>
              clang::Preprocessor &PP; <br>
          <br>
              // Manages the pending replacements. <br>
              class WorkList <br>
              { <br>
              public: <br>
                  typedef std::map<clang::SourceRange,
          std::vector<const StmtToRewrite *>> RangeToRepMap; <br>
          <br>
                  WorkList(clang::ASTContext &ACtx,
          clang::SourceManager &SM); <br>
          <br>
                  bool isStmtPending(const clang::Stmt *S) const; <br>
                  void addStmt(std::unique_ptr<StmtToRewrite> S);
          <br>
                  const RangeToRepMap &getRangeToReplacementsMap()
          const; <br>
                  std::vector<const StmtToRewrite *>
          getSortedReplacements() const; <br>
                  void markDone(const StmtToRewrite *S); <br>
                  void cleanup(); <br>
          <br>
              private: <br>
                  clang::ASTContext &ACtx; <br>
                  clang::SourceManager &SM; <br>
                 
          std::vector<std::unique_ptr<StmtToRewrite>>
          m_pending; <br>
                 
          std::vector<std::unique_ptr<StmtToRewrite>>
          m_done; <br>
                  RangeToRepMap m_rangeToReplacements; <br>
              }; <br>
          <br>
              WorkList m_workList; <br>
          }; <br>
          <br>
          } // namespace cu <br>
          <br>
          #endif <br>
          <br>
          <br>
          <br>
          ---------------------------------------- <br>
          <br>
          RewriteManager.cpp <br>
          <br>
          ---------------------------------------- <br>
          <br>
          #include "ClangUtil/RewriteManager.h" <br>
          #include "ClangUtil/ASTUtil.h" <br>
          #include "clang/Lex/Lexer.h" <br>
          #include "clang/Lex/Preprocessor.h" <br>
          #include "clang/Lex/PreprocessorOptions.h" <br>
          #include "clang/Lex/TokenConcatenation.h" <br>
          #include "clang/Lex/MacroArgs.h" <br>
          <br>
          <br>
          using namespace cu; <br>
          <br>
          <br>
          // Returns a Stmt that is the first parent of startS whose
          expansion range is within the given range. <br>
          static const clang::Stmt *GetFullMacroStmt(clang::SourceRange
          range, const clang::Stmt *startS, clang::ASTContext &ACtx)
          <br>
          { <br>
              auto &SM = ACtx.getSourceManager(); <br>
          <br>
              // Walk the tree upwards until ST does no longer expand to
          within range. <br>
              const clang::Stmt *ST = startS; <br>
              while (true) <br>
              { <br>
                  const auto &parents = ACtx.getParents(*ST); <br>
                  if (parents.empty()) <br>
                  { <br>
                      break; <br>
                  } <br>
                  auto childS = ST; <br>
                  ST = parents[0].get<clang::Stmt>(); <br>
                  if (!ST) <br>
                  { <br>
                      if (auto D = parents[0].get<clang::Decl>())
          <br>
                      { <br>
                          const auto &parentsD =
          ACtx.getParents(*D); <br>
                          if (parentsD.empty()) <br>
                          { <br>
                              break; <br>
                          } <br>
                          ST = parentsD[0].get<clang::Stmt>(); <br>
                          if (!ST) <br>
                          { <br>
                              break; <br>
                          } <br>
                      } <br>
                      else <br>
                      { <br>
                          break; <br>
                      } <br>
                  } <br>
          <br>
                  auto exLocS =
          SM.getExpansionLoc(ST->getLocStart()); <br>
                  auto exLocE = SM.getExpansionLoc(ST->getLocEnd());
          <br>
                  if (SM.isBeforeInTranslationUnit(exLocS,
          range.getBegin()) || <br>
                      SM.isBeforeInTranslationUnit(range.getEnd(),
          exLocE)) <br>
                  { <br>
                      return childS; <br>
                  } <br>
              } <br>
          <br>
              return nullptr; <br>
          } <br>
          <br>
          <br>
          RewriteManager *StmtToRewrite::getMgr() const <br>
          { <br>
              return m_mgr; <br>
          } <br>
          <br>
          <br>
          RewriteManager::WorkList::WorkList(clang::ASTContext
          &ACtx, clang::SourceManager &SM) : ACtx(ACtx), SM(SM)
          {} <br>
          bool RewriteManager::WorkList::isStmtPending(const clang::Stmt
          *S) const <br>
          { <br>
              for (const auto &r : m_pending) <br>
              { <br>
                  if (r->replaceS == S) <br>
                  { <br>
                      return true; <br>
                  } <br>
              } <br>
              return false; <br>
          } <br>
          void
          RewriteManager::WorkList::addStmt(std::unique_ptr<StmtToRewrite>
          S) <br>
          { <br>
              // Use the expansion range for maximal replacement
          flexibility in macros. <br>
              auto replaceRange =
          SM.getExpansionRange(S->replaceS->getSourceRange()); <br>
          <br>
              // TODO not quite correct. <br>
              /*auto sortRanges = [&](std::vector<const
          StmtToRewrite *> &vec) { <br>
                  std::sort(vec.begin(), vec.end(), [&](const
          StmtToRewrite *lhs, const StmtToRewrite *rhs) { <br>
                      auto lhsRange =
          SM.getExpansionRange(lhs->replaceS->getSourceRange()); <br>
                      auto rhsRange =
          SM.getExpansionRange(rhs->replaceS->getSourceRange()); <br>
                      return IsContained(rhsRange, lhsRange, SM); <br>
                  }); <br>
              };*/ <br>
          <br>
              // Establish hierarchical relation between all ranges. <br>
              bool found = false; <br>
              // First, check if this range is within one we already
          have. <br>
              for (auto &r : m_rangeToReplacements) <br>
              { <br>
                  if (IsContained(replaceRange, r.first, SM)) <br>
                  { <br>
                      // Insert in a sorted order. <br>
                      for (auto it = r.second.begin(); it !=
          r.second.end(); ++it) <br>
                      { <br>
                          //auto testRange =
          SM.getExpansionRange((*it)->replaceS->getSourceRange());
          <br>
                          // if (IsContained(testRange, replaceRange,
          SM)) <br>
                          if (IsParent(S->replaceS,
          (*it)->replaceS, ACtx)) <br>
                          { <br>
                              r.second.insert(it, S.get()); <br>
                              found = true; <br>
                              break; <br>
                          } <br>
                      } <br>
                      if (!found) <br>
                      { <br>
                          r.second.push_back(S.get()); <br>
                          found = true; <br>
                      } <br>
                      break; <br>
                  } <br>
              } <br>
              // Not within existing range, add as new top-level range.
          <br>
              if (!found) <br>
              { <br>
                  // Check if any existing ranges are contained within
          the new one. <br>
                  std::vector<const StmtToRewrite *> moveThese; <br>
                  auto it = m_rangeToReplacements.begin(); <br>
                  while (it != m_rangeToReplacements.end()) <br>
                  { <br>
                      if (IsContained(it->first, replaceRange, SM)) <br>
                      { <br>
                          moveThese.insert(moveThese.end(),
          it->second.begin(), it->second.end()); <br>
                          it = m_rangeToReplacements.erase(it); <br>
                      } <br>
                      else <br>
                      { <br>
                          ++it; <br>
                      } <br>
                  } <br>
                  auto &accesses =
          m_rangeToReplacements[replaceRange]; <br>
                  // The order is important here. We want the first
          element to be the one that spans the full range. <br>
                  accesses.push_back(S.get()); <br>
                  // TODO sort "moveThese". <br>
                  accesses.insert(accesses.end(), moveThese.begin(),
          moveThese.end()); <br>
              } <br>
          <br>
              int count = 0; <br>
              for (const auto &r : m_rangeToReplacements) <br>
              { <br>
                  printf("range %i\n", count++); <br>
                  for (const auto &a : r.second) <br>
                  { <br>
                      printf("replacement:\n"); <br>
                      a->replaceS->dump(); <br>
                  } <br>
              } <br>
          <br>
              m_pending.push_back(std::move(S)); <br>
          } <br>
          const RewriteManager::WorkList::RangeToRepMap
          &RewriteManager::WorkList::getRangeToReplacementsMap()
          const <br>
          { <br>
              return m_rangeToReplacements; <br>
          } <br>
          std::vector<const StmtToRewrite *>
          RewriteManager::WorkList::getSortedReplacements() const <br>
          { <br>
              std::vector<const StmtToRewrite *> result; <br>
              for (auto &r : m_rangeToReplacements) <br>
              { <br>
                  result.insert(result.end(), r.second.begin(),
          r.second.end()); <br>
              } <br>
              return result; <br>
          } <br>
          void RewriteManager::WorkList::markDone(const StmtToRewrite
          *S) <br>
          { <br>
              // Remove from hierarchy. <br>
              for (auto &r : m_rangeToReplacements) <br>
              { <br>
                  r.second.erase(std::remove(r.second.begin(),
          r.second.end(), S), r.second.end()); <br>
              } <br>
          <br>
              // Move from pending to done list. <br>
              auto it = std::find_if(m_pending.begin(), m_pending.end(),
          <br>
                                     [&](const
          std::unique_ptr<StmtToRewrite> &rep) { return
          rep.get() == S; }); <br>
              if (it == m_pending.end()) <br>
              { <br>
                  throw std::runtime_error("Did not find replacement to
          mark as done"); <br>
              } <br>
              m_done.push_back(std::move(*it)); <br>
              m_pending.erase(it); <br>
          } <br>
          void RewriteManager::WorkList::cleanup() <br>
          { <br>
              m_done.clear(); <br>
          } <br>
          <br>
          <br>
          RewriteManager::RewriteManager(clang::ASTContext &ACtx,
          clang::Preprocessor &PP) <br>
              : ACtx(ACtx), LangOpts(ACtx.getLangOpts()),
          SM(ACtx.getSourceManager()), PP(PP), m_workList(ACtx, SM) <br>
          { <br>
          } <br>
          <br>
          void
          RewriteManager::registerStmt(std::unique_ptr<StmtToRewrite>
          S) <br>
          { <br>
              if (!S->replaceS) <br>
              { <br>
                  throw std::runtime_error("Must set replaceS"); <br>
              } <br>
          <br>
              if (m_workList.isStmtPending(S->replaceS)) <br>
              { <br>
                  throw std::runtime_error("This Stmt will already be
          replaced"); <br>
              } <br>
          <br>
              S->m_mgr = this; <br>
              m_workList.addStmt(std::move(S)); <br>
          } <br>
          <br>
          RewriteOperation RewriteManager::getReplaced(const clang::Stmt
          *S) <br>
          { <br>
              auto range = SM.getExpansionRange(S->getSourceRange());
          <br>
              return { range, getExpandedCode(S) }; <br>
          } <br>
          <br>
          std::vector<RewriteOperation>
          RewriteManager::getReplacements() <br>
          { <br>
              std::vector<RewriteOperation> results; <br>
          <br>
              for (auto &rangeAndAccesses :
          m_workList.getRangeToReplacementsMap()) <br>
              { <br>
                  auto &range = rangeAndAccesses.first; <br>
                  auto &accesses = rangeAndAccesses.second; <br>
          <br>
                  // Cannot replace something inside a macro because it
          would replace all expansions instead of just the selected <br>
                  // AST node. So in a first step, get an enclosing
          statement that is no longer inside a macro. <br>
                  // TODO we could keep the original code more clean by
          not expanding macro args if the whole expansion does not <br>
                  // contain the macro arg more than once. <br>
                  auto macroS = GetFullMacroStmt(range,
          accesses[0]->replaceS, ACtx); <br>
          <br>
                  results.push_back(getReplaced(macroS)); <br>
          <br>
                  // TODO we could run clang-format on the replacements.
          this would especially benefit long macro expansions. <br>
              } <br>
          <br>
              m_workList.cleanup(); <br>
          <br>
              return results; <br>
          } <br>
          <br>
          std::string RewriteManager::getExpandedCode(const clang::Stmt
          *toReplaceS) <br>
          { <br>
              // TODO performance optimization. this is parsing way more
          than required. <br>
          <br>
              using namespace clang; <br>
          <br>
              printf("getExpandedCode:\n"); <br>
              toReplaceS->dump(); <br>
          <br>
              std::string out; <br>
          <br>
              auto toReplaceExpStart =
          SM.getExpansionLoc(toReplaceS->getLocStart()); <br>
              auto toReplaceExpEnd =
          SM.getExpansionLoc(toReplaceS->getLocEnd()); <br>
              auto toReplaceSpellStart =
          SM.getSpellingLoc(toReplaceS->getLocStart()); <br>
              auto toReplaceSpellEnd =
          SM.getSpellingLoc(toReplaceS->getLocEnd()); <br>
          <br>
              auto FID =
          SM.getFileID(SM.getExpansionLoc(toReplaceS->getLocStart()));
          <br>
          <br>
              // The following is inspired by:
          clang/Rewrite/HTMLRewrite.cpp:HighlightMacros <br>
          <br>
              // Re-lex the raw token stream into a token buffer. <br>
              std::vector<Token> TokenStream; <br>
          <br>
              const llvm::MemoryBuffer *FromFile = SM.getBuffer(FID); <br>
              Lexer L(FID, FromFile, SM, PP.getLangOpts()); <br>
          <br>
              // Lex all the tokens in raw mode, to avoid entering
          #includes or expanding <br>
              // macros. <br>
              while (1) <br>
              { <br>
                  Token Tok; <br>
                  L.LexFromRawLexer(Tok); <br>
          <br>
                  // If this is a # at the start of a line, discard it
          from the token stream. <br>
                  // We don't want the re-preprocess step to see
          #defines, #includes or other <br>
                  // preprocessor directives. <br>
                  if (Tok.is(tok::hash) &&
          Tok.isAtStartOfLine()) <br>
                      continue; <br>
          <br>
                  // If this is a ## token, change its kind to unknown
          so that repreprocessing <br>
                  // it will not produce an error. <br>
                  if (Tok.is(tok::hashhash)) <br>
                      Tok.setKind(tok::unknown); <br>
          <br>
                  // If this raw token is an identifier, the raw lexer
          won't have looked up <br>
                  // the corresponding identifier info for it.  Do this
          now so that it will be <br>
                  // macro expanded when we re-preprocess it. <br>
                  if (Tok.is(tok::raw_identifier)) <br>
                      PP.LookUpIdentifierInfo(Tok); <br>
          <br>
                  TokenStream.push_back(Tok); <br>
          <br>
                  for (auto &rep :
          m_workList.getSortedReplacements()) <br>
                  { <br>
                      auto repS = rep->replaceS; <br>
                      auto spellLoc =
          SM.getSpellingLoc(repS->getLocStart()); <br>
                      if (SM.getSpellingLoc(Tok.getLocation()) ==
          spellLoc) <br>
                      { <br>
                          // <br>
                      } <br>
                  } <br>
          <br>
                  if (Tok.is(tok::eof)) <br>
                      break; <br>
              } <br>
          <br>
              // Temporarily change the diagnostics object so that we
          ignore any generated <br>
              // diagnostics from this pass. <br>
              DiagnosticsEngine
          TmpDiags(PP.getDiagnostics().getDiagnosticIDs(),
          &PP.getDiagnostics().getDiagnosticOptions(), <br>
                                         new IgnoringDiagConsumer); <br>
          <br>
              // Copy the preprocessor and all of its state. <br>
              auto PPOpts =
          std::make_shared<PreprocessorOptions>(PP.getPreprocessorOpts());
          <br>
              LangOptions LO = PP.getLangOpts(); <br>
              Preprocessor TmpPP(PPOpts, TmpDiags, LO, SM,
          PP.getPCMCache(), PP.getHeaderSearchInfo(),
          PP.getModuleLoader(), <br>
          PP.getIdentifierTable().getExternalIdentifierLookup()); <br>
              TmpPP.Initialize(PP.getTargetInfo(),
          PP.getAuxTargetInfo()); <br>
              TmpPP.setExternalSource(PP.getExternalSource()); <br>
              TmpPP.setPreprocessedOutput(true); <br>
          <br>
              std::map<const clang::IdentifierInfo *, bool>
          MacroPreviouslyEnabled; <br>
              for (const auto &m : PP.macros()) <br>
              { <br>
                  // printf("PREDEF MACRO: %s\n",
          m.first->getName().str().c_str()); <br>
                  TmpPP.getMacroDefinition(m.first); <br>
          <br>
                  for (const auto &tmpm : TmpPP.macros()) <br>
                  { <br>
                      if (tmpm.first == m.first) <br>
                      { <br>
                          auto MD = m.second.getLatest(); <br>
                          auto MI = MD->getMacroInfo(); <br>
                          // If this is a recursive call we might be in
          a macro expansion and the macro might be disabled. We need <br>
                          // to enable it for now so that all expansions
          work. Restore it later. <br>
                          MacroPreviouslyEnabled[tmpm.first] =
          MI->isEnabled(); <br>
                          if (!MI->isEnabled()) <br>
                          { <br>
                              MD->getMacroInfo()->EnableMacro(); <br>
                          } <br>
          <br>
                          // This should not change anything since we
          just copy data over. <br>
                          auto &mutableState =
          const_cast<std::remove_const<decltype(tmpm.second)>::type
          &>(tmpm.second); <br>
                          mutableState.setLatest(MD); <br>
                          break; <br>
                      } <br>
                  } <br>
              } <br>
          <br>
              class MacroArgCollector : public clang::PPCallbacks <br>
              { <br>
              public: <br>
                  MacroArgCollector(Preprocessor &TmpPP) :
          TmpPP(TmpPP) {} <br>
          <br>
                  void MacroExpands(const Token &Tok, const
          MacroDefinition &MD, SourceRange Range, const MacroArgs
          *Args) override <br>
                  { <br>
                      if (!Args) <br>
                      { <br>
                          return; <br>
                      } <br>
                      printf("GOT MACRO ARGS EXPANSION CALLBACK\n"); <br>
                      for (int i = 0; i <
          (int)Args->getNumMacroArguments(); i++) <br>
                      { <br>
                          auto TokUnex = Args->getUnexpArgument(i); <br>
                          // Thats just non-const for a cache, so should
          be fine. <br>
                          auto TokPreExp = const_cast<MacroArgs
          *>(Args)->getPreExpArgument(i, TmpPP); <br>
                          printf("unexp: %s\n",
          TmpPP.getSpelling(*TokUnex).c_str()); <br>
                          for (const auto &T : TokPreExp) <br>
                          { <br>
                              printf("preexp: %s\n",
          TmpPP.getSpelling(T).c_str()); <br>
                          } <br>
                      } <br>
                  } <br>
          <br>
                  Preprocessor &TmpPP; <br>
              }; <br>
TmpPP.addPPCallbacks(std::make_unique<MacroArgCollector>(TmpPP));
          <br>
              // Instead: collect the macro arg info in the law lexing
          step above. or do another pass that uses the PP but without
          expansions. <br>
          <br>
              /*printf("DUMP MACRO INFO\n"); <br>
              for (const auto &m : PP.macros()) <br>
                  PP.dumpMacroInfo(m.first); <br>
              printf("---\n"); <br>
              for (const auto &m : TmpPP.macros()) <br>
                  TmpPP.dumpMacroInfo(m.first); <br>
              printf("DUMP MACRO INFO END\n");*/ <br>
          <br>
              DiagnosticsEngine *OldDiags = &TmpPP.getDiagnostics();
          <br>
          <br>
              // Inform the preprocessor that we don't want comments. <br>
              TmpPP.SetCommentRetentionState(false, false); <br>
          <br>
              // We don't want pragmas either. Although we filtered out
          #pragma, removing <br>
              // _Pragma and __pragma is much harder. <br>
              bool PragmasPreviouslyEnabled = TmpPP.getPragmasEnabled();
          <br>
              TmpPP.setPragmasEnabled(false); <br>
          <br>
              // Enter the tokens we just lexed.  This will cause them
          to be macro expanded <br>
              // but won't enter sub-files (because we removed #'s). <br>
              TmpPP.EnterTokenStream(TokenStream, false); <br>
          <br>
              TokenConcatenation ConcatInfo(TmpPP); <br>
          <br>
              // Lex all the tokens. <br>
              Token Tok; <br>
              TmpPP.Lex(Tok); <br>
          <br>
              std::map<SourceLocation, int> slocIdx; <br>
          <br>
              auto checkReplacement = [&]() { <br>
                  for (auto &rep :
          m_workList.getSortedReplacements()) <br>
                  { <br>
                      // auto rep = r.second.get(); <br>
                      auto repS = rep->replaceS; <br>
                      auto spellLoc =
          SM.getSpellingLoc(repS->getLocStart()); <br>
                      // TODO we need to check here if the repS spans
          the full range (or largest?) <br>
                      if (SM.getSpellingLoc(Tok.getLocation()) ==
          spellLoc) <br>
                      { <br>
                          if (slocIdx[spellLoc] == 7) <br>
                          { <br>
                              // replace <br>
                          } <br>
                          slocIdx[spellLoc]++; <br>
          <br>
                          // Done replacing that one, but have to keep
          it alive until we're done with it. <br>
                          m_workList.markDone(rep); <br>
          <br>
                          printf("[[[\n"); <br>
                          auto repStr = rep->makeReplaceStr(); <br>
                          printf("REPLACED: %s ]]]\n", repStr.c_str());
          <br>
                          out += repStr; <br>
          <br>
                          // Skip ahead until after the whole
          replacement. <br>
                          auto repEnd =
          SM.getSpellingLoc(repS->getLocEnd()); <br>
                          while (repEnd !=
          SM.getSpellingLoc(Tok.getLocation())) <br>
                          { <br>
                              TmpPP.Lex(Tok); <br>
                              assert(!Tok.is(tok::eof) && "End
          not found"); <br>
                          } <br>
          <br>
                          // Eat one more since we stopped at the end
          token and we want to continue after it. <br>
                          TmpPP.Lex(Tok); <br>
          <br>
                          return true; <br>
                      } <br>
                  } <br>
                  return false; <br>
              }; <br>
          <br>
              while (Tok.isNot(tok::eof)) <br>
              { <br>
                  printf("TOKEN: %s\n", TmpPP.getSpelling(Tok).c_str());
          <br>
          <br>
                  auto TokLoc = Tok.getLocation(); <br>
                  auto TokExp = SM.getExpansionLoc(TokLoc); <br>
                  if (SM.isBeforeInTranslationUnit(toReplaceExpEnd,
          TokExp)) <br>
                  { <br>
                      // Anything after the Stmt we want to replace is
          not interesting. <br>
                      break; <br>
                  } <br>
          <br>
                  // Skip ahead until we are at the expansion start of
          the Stmt we want to replace. <br>
                  if (!SM.isBeforeInTranslationUnit(TokLoc,
          toReplaceExpStart)) <br>
                  { <br>
                      if (TokLoc.isMacroID()) <br>
                      { <br>
                          // This is the first token of a macro
          expansion. <br>
                          auto LLoc = SM.getExpansionRange(TokLoc); <br>
          <br>
                          // Ignore tokens whose instantiation location
          was not the main file. <br>
                          if (SM.getFileID(LLoc.first) != FID) <br>
                          { <br>
                              TmpPP.Lex(Tok); <br>
                              continue; <br>
                          } <br>
          <br>
                          assert(SM.getFileID(LLoc.second) == FID
          && <br>
                                 "Start and end of expansion must be in
          the same ultimate file!"); <br>
          <br>
                          bool stopOutputOnNextToken = false; <br>
                          bool toReplaceStartsInMacro =
          toReplaceExpStart == TokExp; <br>
                          bool toReplaceEndsInMacro = toReplaceExpEnd ==
          TokExp; <br>
                          bool startedOutput = false; <br>
          <br>
                          Token PrevPrevTok; <br>
                          Token PrevTok = Tok; <br>
          <br>
                          while (!Tok.is(tok::eof) &&
          SM.getExpansionLoc(Tok.getLocation()) == LLoc.first) <br>
                          { <br>
                              printf("TOKEN (in macro): %s\n",
          TmpPP.getSpelling(Tok).c_str()); <br>
          <br>
                              auto TokSpell =
          SM.getSpellingLoc(Tok.getLocation()); <br>
                              if (stopOutputOnNextToken) <br>
                              { <br>
                                  break; <br>
                              } <br>
                              if (toReplaceEndsInMacro &&
          TokSpell == toReplaceSpellEnd) <br>
                              { <br>
                                  stopOutputOnNextToken = true; <br>
                              } <br>
          <br>
                              if (toReplaceStartsInMacro &&
          !startedOutput) <br>
                              { <br>
                                  if (TokSpell == toReplaceSpellStart) <br>
                                  { <br>
                                      startedOutput = true; <br>
                                  } <br>
                                  else <br>
                                  { <br>
                                      TmpPP.Lex(Tok); <br>
                                      continue; <br>
                                  } <br>
                              } <br>
          <br>
                              // If the tokens were already space
          separated, or if they must be to avoid <br>
                              // them being implicitly pasted, add a
          space between them. <br>
                              if (Tok.hasLeadingSpace() ||
          ConcatInfo.AvoidConcat(PrevPrevTok, PrevTok, Tok)) <br>
                                  out += ' '; <br>
          <br>
                              if (checkReplacement()) <br>
                              { <br>
                                  continue; <br>
                              } <br>
          <br>
                              out += TmpPP.getSpelling(Tok); <br>
                              TmpPP.Lex(Tok); <br>
                          } <br>
                          if (stopOutputOnNextToken) <br>
                          { <br>
                              break; <br>
                          } <br>
                      } <br>
                      else <br>
                      { <br>
                          if (checkReplacement()) <br>
                          { <br>
                              continue; <br>
                          } <br>
          <br>
                          // Output original code because we are outside
          of a replacement. <br>
                          out += TmpPP.getSpelling(Tok); <br>
                          TmpPP.Lex(Tok); <br>
                      } <br>
                  } <br>
                  else <br>
                  { <br>
                      TmpPP.Lex(Tok); <br>
                  } <br>
              } <br>
          <br>
              // Restore the preprocessor's old state. <br>
              TmpPP.setDiagnostics(*OldDiags); <br>
              TmpPP.setPragmasEnabled(PragmasPreviouslyEnabled); <br>
          <br>
              for (const auto &tmpm : TmpPP.macros()) <br>
              { <br>
                  auto it = MacroPreviouslyEnabled.find(tmpm.first); <br>
                  if (it != MacroPreviouslyEnabled.end()) <br>
                  { <br>
                      auto MD = tmpm.second.getLatest(); <br>
                      auto MI = MD->getMacroInfo(); <br>
                      if (MI->isEnabled() && !it->second)
          <br>
                      { <br>
                          MI->DisableMacro(); <br>
                      } <br>
                      else if (!MI->isEnabled() &&
          it->second) <br>
                      { <br>
                          MI->EnableMacro(); <br>
                      } <br>
                  } <br>
              } <br>
          <br>
              return out; <br>
          } <br>
          <br>
          <br>
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