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/Frontend/PCHContainerOperations.cpp b/clang/lib/Frontend/PCHContainerOperations.cpp
index 2d4edde..2c867e7 100644
--- a/clang/lib/Frontend/PCHContainerOperations.cpp
+++ b/clang/lib/Frontend/PCHContainerOperations.cpp
@@ -60,8 +60,7 @@ std::unique_ptr<ASTConsumer> RawPCHContainerWriter::CreatePCHContainerGenerator(
 
 void RawPCHContainerReader::ExtractPCH(
     llvm::MemoryBufferRef Buffer, llvm::BitstreamReader &StreamFile) const {
-  StreamFile.init((const unsigned char *)Buffer.getBufferStart(),
-                  (const unsigned char *)Buffer.getBufferEnd());
+  StreamFile = llvm::BitstreamReader(Buffer);
 }
 
 PCHContainerOperations::PCHContainerOperations() {