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, 4 deletions

diff --git a/clang/lib/Frontend/SerializedDiagnosticReader.cpp b/clang/lib/Frontend/SerializedDiagnosticReader.cpp
index 05dc8518c38..aefd0f8fbb0 100644
--- a/clang/lib/Frontend/SerializedDiagnosticReader.cpp
+++ b/clang/lib/Frontend/SerializedDiagnosticReader.cpp
@@ -24,10 +24,7 @@ std::error_code SerializedDiagnosticReader::readDiagnostics(StringRef File) {
   if (!Buffer)
     return SDError::CouldNotLoad;
 
-  llvm::BitstreamReader StreamFile;
-  StreamFile.init((const unsigned char *)(*Buffer)->getBufferStart(),
-                  (const unsigned char *)(*Buffer)->getBufferEnd());
-
+  llvm::BitstreamReader StreamFile(**Buffer);
   llvm::BitstreamCursor Stream(StreamFile);
 
   // Sniff for the signature.