From: Sebastian Redl <sebastian.redl@getdesigned.at>
Date: Tue, 20 Jul 2010 21:50:20 +0000 (+0000)
Subject: Allow loading source locations from any file in the chain. WIP
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=190faf7c30890479925193b074571e5dc30c3f53;p=clang

Allow loading source locations from any file in the chain. WIP

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@108942 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/SourceManager.h b/include/clang/Basic/SourceManager.h
index 6a4be46094..5d98fb9253 100644
--- a/include/clang/Basic/SourceManager.h
+++ b/include/clang/Basic/SourceManager.h
@@ -435,7 +435,7 @@ public:
   /// createFileID - Create a new FileID that represents the specified file
   /// being #included from the specified IncludePosition.  This returns 0 on
   /// error and translates NULL into standard input.
-  /// PreallocateID should be non-zero to specify which a pre-allocated,
+  /// PreallocateID should be non-zero to specify which pre-allocated,
   /// lazily computed source location is being filled in by this operation.
   FileID createFileID(const FileEntry *SourceFile, SourceLocation IncludePos,
                       SrcMgr::CharacteristicKind FileCharacter,
diff --git a/include/clang/Frontend/PCHReader.h b/include/clang/Frontend/PCHReader.h
index 86a1a006bd..c3826e7a17 100644
--- a/include/clang/Frontend/PCHReader.h
+++ b/include/clang/Frontend/PCHReader.h
@@ -271,6 +271,7 @@ private:
 
   /// \brief The chain of PCH files. The first entry is the one named by the
   /// user, the last one is the one that doesn't depend on anything further.
+  /// That is, the entry I was created with -include-pch I+1.
   llvm::SmallVector<PerFileData*, 2> Chain;
 
   /// \brief Types that have already been loaded from the PCH file.
@@ -539,6 +540,7 @@ private:
   bool ParseLineTable(llvm::SmallVectorImpl<uint64_t> &Record);
   PCHReadResult ReadSourceManagerBlock(PerFileData &F);
   PCHReadResult ReadSLocEntryRecord(unsigned ID);
+  llvm::BitstreamCursor &SLocCursorForID(unsigned ID);
 
   bool ParseLanguageOptions(const llvm::SmallVectorImpl<uint64_t> &Record);
   QualType ReadTypeRecord(uint64_t Offset);
diff --git a/lib/Frontend/PCHReader.cpp b/lib/Frontend/PCHReader.cpp
index b12025fdb8..126036ac4e 100644
--- a/lib/Frontend/PCHReader.cpp
+++ b/lib/Frontend/PCHReader.cpp
@@ -953,6 +953,26 @@ PCHReader::PCHReadResult PCHReader::ReadSourceManagerBlock(PerFileData &F) {
   }
 }
 
+/// \brief Get a cursor that's correctly positioned for reading the source
+/// location entry with the given ID.
+llvm::BitstreamCursor &PCHReader::SLocCursorForID(unsigned ID) {
+  assert(ID != 0 && ID <= TotalNumSLocEntries &&
+         "SLocCursorForID should only be called for real IDs.");
+
+  ID -= 1;
+  PerFileData *F = 0;
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    F = Chain[N - I - 1];
+    if (ID < F->LocalNumSLocEntries)
+      break;
+    ID -= F->LocalNumSLocEntries;
+  }
+  assert(F && F->LocalNumSLocEntries > ID && "Chain corrupted");
+
+  F->SLocEntryCursor.JumpToBit(F->SLocOffsets[ID]);
+  return F->SLocEntryCursor;
+}
+
 /// \brief Read in the source location entry with the given ID.
 PCHReader::PCHReadResult PCHReader::ReadSLocEntryRecord(unsigned ID) {
   if (ID == 0)
@@ -963,10 +983,9 @@ PCHReader::PCHReadResult PCHReader::ReadSLocEntryRecord(unsigned ID) {
     return Failure;
   }
 
-  llvm::BitstreamCursor &SLocEntryCursor = Chain[0]->SLocEntryCursor;
+  llvm::BitstreamCursor &SLocEntryCursor = SLocCursorForID(ID);
 
   ++NumSLocEntriesRead;
-  SLocEntryCursor.JumpToBit(Chain[0]->SLocOffsets[ID - 1]);
   unsigned Code = SLocEntryCursor.ReadCode();
   if (Code == llvm::bitc::END_BLOCK ||
       Code == llvm::bitc::ENTER_SUBBLOCK ||