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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285773 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 6 deletions

diff --git a/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp b/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
index 96820f9c8a0..fec11e35d50 100644
--- a/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
+++ b/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
@@ -436,10 +436,6 @@ static bool decodeMetadataStringsBlob(BitstreamReader &Reader, StringRef Indent,
   SimpleBitstreamCursor R(Reader);
   R.jumpToPointer(Lengths.begin());
 
-  // Ensure that Blob doesn't get invalidated, even if this is reading from a
-  // StreamingMemoryObject with corrupt data.
-  R.setArtificialByteLimit(R.getCurrentByteNo() + StringsOffset);
-
   StringRef Strings = Blob.drop_front(StringsOffset);
   do {
     if (R.AtEndOfStream())
@@ -735,7 +731,7 @@ static bool openBitcodeFile(StringRef Path,
       return ReportError("Invalid bitcode wrapper header");
   }
 
-  StreamFile = BitstreamReader(BufPtr, EndBufPtr);
+  StreamFile = BitstreamReader(ArrayRef<uint8_t>(BufPtr, EndBufPtr));
   Stream = BitstreamCursor(StreamFile);
   StreamFile.CollectBlockInfoNames();
 
@@ -814,7 +810,7 @@ static int AnalyzeBitcode() {
 
   if (Dump) outs() << "\n\n";
 
-  uint64_t BufferSizeBits = StreamFile.getBitcodeBytes().getExtent() * CHAR_BIT;
+  uint64_t BufferSizeBits = StreamFile.getBitcodeBytes().size() * CHAR_BIT;
   // Print a summary of the read file.
   outs() << "Summary of " << InputFilename << ":\n";
   outs() << "         Total size: ";