Bitcode: Change reader interface to take memory buffers.

As proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/106595.html

This change also fixes an API oddity where BitstreamCursor::Read() would
return zero for the first read past the end of the bitstream, but would
report_fatal_error for subsequent reads. Now we always report_fatal_error
for all reads past the end. Updated clients to check for the end of the
bitstream before reading from it.

I also needed to add padding to the invalid bitcode tests in
test/Bitcode/. This is because the streaming interface was not checking that
the file size is a multiple of 4.

Differential Revision: https://reviews.llvm.org/D26219

llvm-svn: 285773

1 files changed, 1 insertions, 2 deletions

diff --git a/clang/lib/Serialization/GlobalModuleIndex.cpp b/clang/lib/Serialization/GlobalModuleIndex.cpp
index f75bc5260cc..e55ed40b227 100644
--- a/clang/lib/Serialization/GlobalModuleIndex.cpp
+++ b/clang/lib/Serialization/GlobalModuleIndex.cpp
@@ -246,8 +246,7 @@ GlobalModuleIndex::readIndex(StringRef Path) {
   std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(BufferOrErr.get());
 
   /// \brief The bitstream reader from which we'll read the AST file.
-  llvm::BitstreamReader Reader((const unsigned char *)Buffer->getBufferStart(),
-                               (const unsigned char *)Buffer->getBufferEnd());
+  llvm::BitstreamReader Reader(*Buffer);
 
   /// \brief The main bitstream cursor for the main block.
   llvm::BitstreamCursor Cursor(Reader);