[PCH] Serialize skipped preprocessor ranges

The skipped preprocessor ranges are now serialized in the AST PCH file. This fixes, for example, libclang's clang_getSkippedRanges() returning zero ranges after reparsing a translation unit.

Differential Revision: https://reviews.llvm.org/D20124

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@322503 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 17 insertions, 1 deletions

diff --git a/include/clang/Lex/PreprocessingRecord.h b/include/clang/Lex/PreprocessingRecord.h
index 5f7a6efcef..77da1eb26f 100644
--- a/include/clang/Lex/PreprocessingRecord.h
+++ b/include/clang/Lex/PreprocessingRecord.h
@@ -297,6 +297,9 @@ class Token;
                                                         FileID FID) {
       return None;
     }
+
+    /// \brief Read a preallocated skipped range from the external source.
+    virtual SourceRange ReadSkippedRange(unsigned Index) = 0;
   };
   
   /// \brief A record of the steps taken while preprocessing a source file,
@@ -322,6 +325,8 @@ class Token;
     /// \brief The set of ranges that were skipped by the preprocessor,
     std::vector<SourceRange> SkippedRanges;
 
+    bool SkippedRangesAllLoaded = true;
+
     /// \brief Global (loaded or local) ID for a preprocessed entity.
     /// Negative values are used to indicate preprocessed entities
     /// loaded from the external source while non-negative values are used to
@@ -377,6 +382,16 @@ class Token;
     /// corresponds to the first newly-allocated entity.
     unsigned allocateLoadedEntities(unsigned NumEntities);
 
+    /// \brief Allocate space for a new set of loaded preprocessed skipped
+    /// ranges.
+    ///
+    /// \returns The index into the set of loaded preprocessed ranges, which
+    /// corresponds to the first newly-allocated range.
+    unsigned allocateSkippedRanges(unsigned NumRanges);
+
+    /// \brief Ensures that all external skipped ranges have been loaded.
+    void ensureSkippedRangesLoaded();
+
     /// \brief Register a new macro definition.
     void RegisterMacroDefinition(MacroInfo *Macro, MacroDefinitionRecord *Def);
 
@@ -499,7 +514,8 @@ class Token;
     MacroDefinitionRecord *findMacroDefinition(const MacroInfo *MI);
 
     /// \brief Retrieve all ranges that got skipped while preprocessing.
-    const std::vector<SourceRange> &getSkippedRanges() const {
+    const std::vector<SourceRange> &getSkippedRanges() {
+      ensureSkippedRangesLoaded();
       return SkippedRanges;
     }