r246534 - [modules] When emitting line tables, only emit filenames that are actually referenced by the entries that we emit.

[Richard Smith via cfe-commits]

Author: rsmith
Date: Tue Sep  1 02:41:55 2015
New Revision: 246534

URL: http://llvm.org/viewvc/llvm-project?rev=246534&view=rev
Log:
[modules] When emitting line tables, only emit filenames that are actually referenced by the entries that we emit.

Modified:
    cfe/trunk/lib/Serialization/ASTReader.cpp
    cfe/trunk/lib/Serialization/ASTWriter.cpp

Modified: cfe/trunk/lib/Serialization/ASTReader.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTReader.cpp?rev=246534&r1=246533&r2=246534&view=diff
==============================================================================
--- cfe/trunk/lib/Serialization/ASTReader.cpp (original)
+++ cfe/trunk/lib/Serialization/ASTReader.cpp Tue Sep  1 02:41:55 2015
@@ -1058,11 +1058,12 @@ bool ASTReader::ParseLineTable(ModuleFil
 
   // Parse the file names
   std::map<int, int> FileIDs;
-  for (int I = 0, N = Record[Idx++]; I != N; ++I) {
+  for (unsigned I = 0; Record[Idx]; ++I) {
     // Extract the file name
     auto Filename = ReadPath(F, Record, Idx);
     FileIDs[I] = LineTable.getLineTableFilenameID(Filename);
   }
+  ++Idx;
 
   // Parse the line entries
   std::vector<LineEntry> Entries;
@@ -1074,7 +1075,7 @@ bool ASTReader::ParseLineTable(ModuleFil
 
     // Extract the line entries
     unsigned NumEntries = Record[Idx++];
-    assert(NumEntries && "Numentries is 00000");
+    assert(NumEntries && "no line entries for file ID");
     Entries.clear();
     Entries.reserve(NumEntries);
     for (unsigned I = 0; I != NumEntries; ++I) {

Modified: cfe/trunk/lib/Serialization/ASTWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTWriter.cpp?rev=246534&r1=246533&r2=246534&view=diff
==============================================================================
--- cfe/trunk/lib/Serialization/ASTWriter.cpp (original)
+++ cfe/trunk/lib/Serialization/ASTWriter.cpp Tue Sep  1 02:41:55 2015
@@ -1981,10 +1981,19 @@ void ASTWriter::WriteSourceManagerBlock(
     LineTableInfo &LineTable = SourceMgr.getLineTable();
 
     Record.clear();
-    // Emit the file names.
-    Record.push_back(LineTable.getNumFilenames());
-    for (unsigned I = 0, N = LineTable.getNumFilenames(); I != N; ++I)
-      AddPath(LineTable.getFilename(I), Record);
+
+    // Emit the needed file names.
+    llvm::DenseMap<int, int> FilenameMap;
+    for (const auto &L : LineTable) {
+      if (L.first.ID < 0)
+        continue;
+      for (auto &LE : L.second) {
+        if (FilenameMap.insert(std::make_pair(LE.FilenameID,
+                                              FilenameMap.size())).second)
+          AddPath(LineTable.getFilename(LE.FilenameID), Record);
+      }
+    }
+    Record.push_back(0);
 
     // Emit the line entries
     for (LineTableInfo::iterator L = LineTable.begin(), LEnd = LineTable.end();
@@ -2003,11 +2012,12 @@ void ASTWriter::WriteSourceManagerBlock(
            LE != LEEnd; ++LE) {
         Record.push_back(LE->FileOffset);
         Record.push_back(LE->LineNo);
-        Record.push_back(LE->FilenameID);
+        Record.push_back(FilenameMap[LE->FilenameID]);
         Record.push_back((unsigned)LE->FileKind);
         Record.push_back(LE->IncludeOffset);
       }
     }
+
     Stream.EmitRecord(SOURCE_MANAGER_LINE_TABLE, Record);
   }
 }