commit c4e4b7e31e8efc917352286aa6e22d78b659d44d
author Zachary Turner <zturner@google.com> Thu May 25 21:12:00 2017 +0000
committer Zachary Turner <zturner@google.com> Thu May 25 21:12:00 2017 +0000
tree ba26d54d6792bb650889f111fc074cec63a4e390
parent 1c154a6107804f4da2bf6baf7b2eeb0ee996dcd3

Fix a bug in MappedBlockStream.

It was using the number of blocks of the entire PDB file as the number
of blocks of each stream that was created.  This was only an issue in
the readLongestContiguousChunk function, which  was never called prior.
This bug surfaced when I updated an algorithm to use this function and
the algorithm broke.

llvm-svn: 303916

llvm/lib/DebugInfo/MSF/MappedBlockStream.cpp

diff --git a/llvm/lib/DebugInfo/MSF/MappedBlockStream.cpp b/llvm/lib/DebugInfo/MSF/MappedBlockStream.cpp
index 57953cf..dfdeb84 100644
--- a/llvm/lib/DebugInfo/MSF/MappedBlockStream.cpp
+++ b/llvm/lib/DebugInfo/MSF/MappedBlockStream.cpp
@@ -45,18 +45,17 @@
                         std::min(I1.second, I2.second));
 }
 
-MappedBlockStream::MappedBlockStream(uint32_t BlockSize, uint32_t NumBlocks,
+MappedBlockStream::MappedBlockStream(uint32_t BlockSize,
                                      const MSFStreamLayout &Layout,
                                      BinaryStreamRef MsfData)
-    : BlockSize(BlockSize), NumBlocks(NumBlocks), StreamLayout(Layout),
-      MsfData(MsfData) {}
+    : BlockSize(BlockSize), StreamLayout(Layout), MsfData(MsfData) {}
 
 std::unique_ptr<MappedBlockStream>
-MappedBlockStream::createStream(uint32_t BlockSize, uint32_t NumBlocks,
+MappedBlockStream::createStream(uint32_t BlockSize,
                                 const MSFStreamLayout &Layout,
                                 BinaryStreamRef MsfData) {
   return llvm::make_unique<MappedBlockStreamImpl<MappedBlockStream>>(
-      BlockSize, NumBlocks, Layout, MsfData);
+      BlockSize, Layout, MsfData);
 }
 
 std::unique_ptr<MappedBlockStream> MappedBlockStream::createIndexedStream(
@@ -66,7 +65,7 @@
   SL.Blocks = Layout.StreamMap[StreamIndex];
   SL.Length = Layout.StreamSizes[StreamIndex];
   return llvm::make_unique<MappedBlockStreamImpl<MappedBlockStream>>(
-      Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+      Layout.SB->BlockSize, SL, MsfData);
 }
 
 std::unique_ptr<MappedBlockStream>
@@ -75,7 +74,7 @@
   MSFStreamLayout SL;
   SL.Blocks = Layout.DirectoryBlocks;
   SL.Length = Layout.SB->NumDirectoryBytes;
-  return createStream(Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+  return createStream(Layout.SB->BlockSize, SL, MsfData);
 }
 
 std::unique_ptr<MappedBlockStream>
@@ -83,7 +82,7 @@
                                    BinaryStreamRef MsfData) {
   MSFStreamLayout SL;
   initializeFpmStreamLayout(Layout, SL);
-  return createStream(Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+  return createStream(Layout.SB->BlockSize, SL, MsfData);
 }
 
 Error MappedBlockStream::readBytes(uint32_t Offset, uint32_t Size,
@@ -173,7 +172,7 @@
   uint32_t First = Offset / BlockSize;
   uint32_t Last = First;
 
-  while (Last < NumBlocks - 1) {
+  while (Last < getNumBlocks() - 1) {
     if (StreamLayout.Blocks[Last] != StreamLayout.Blocks[Last + 1] - 1)
       break;
     ++Last;
@@ -313,17 +312,16 @@
 }
 
 WritableMappedBlockStream::WritableMappedBlockStream(
-    uint32_t BlockSize, uint32_t NumBlocks, const MSFStreamLayout &Layout,
+    uint32_t BlockSize, const MSFStreamLayout &Layout,
     WritableBinaryStreamRef MsfData)
-    : ReadInterface(BlockSize, NumBlocks, Layout, MsfData),
-      WriteInterface(MsfData) {}
+    : ReadInterface(BlockSize, Layout, MsfData), WriteInterface(MsfData) {}
 
 std::unique_ptr<WritableMappedBlockStream>
-WritableMappedBlockStream::createStream(uint32_t BlockSize, uint32_t NumBlocks,
+WritableMappedBlockStream::createStream(uint32_t BlockSize,
                                         const MSFStreamLayout &Layout,
                                         WritableBinaryStreamRef MsfData) {
   return llvm::make_unique<MappedBlockStreamImpl<WritableMappedBlockStream>>(
-      BlockSize, NumBlocks, Layout, MsfData);
+      BlockSize, Layout, MsfData);
 }
 
 std::unique_ptr<WritableMappedBlockStream>
@@ -334,7 +332,7 @@
   MSFStreamLayout SL;
   SL.Blocks = Layout.StreamMap[StreamIndex];
   SL.Length = Layout.StreamSizes[StreamIndex];
-  return createStream(Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+  return createStream(Layout.SB->BlockSize, SL, MsfData);
 }
 
 std::unique_ptr<WritableMappedBlockStream>
@@ -343,7 +341,7 @@
   MSFStreamLayout SL;
   SL.Blocks = Layout.DirectoryBlocks;
   SL.Length = Layout.SB->NumDirectoryBytes;
-  return createStream(Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+  return createStream(Layout.SB->BlockSize, SL, MsfData);
 }
 
 std::unique_ptr<WritableMappedBlockStream>
@@ -351,7 +349,7 @@
                                            WritableBinaryStreamRef MsfData) {
   MSFStreamLayout SL;
   initializeFpmStreamLayout(Layout, SL);
-  return createStream(Layout.SB->BlockSize, Layout.SB->NumBlocks, SL, MsfData);
+  return createStream(Layout.SB->BlockSize, SL, MsfData);
 }
 
 Error WritableMappedBlockStream::readBytes(uint32_t Offset, uint32_t Size,