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lib/Bitcode/NaCl/Reader/NaClBitcodeReader.cpp

 //===- NaClBitcodeReader.cpp ----------------------------------------------===//
 //     Internal NaClBitcodeReader implementation
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
@@ skipping 979 matching lines @@
   // PNaCl does not support different DataLayouts in pexes, so we
   // implicitly set the DataLayout to the following default.
   //
   // This is not usually needed by the backend, but it might be used
   // by IR passes that the PNaCl translator runs.  We set this in the
   // reader rather than in pnacl-llc so that 'opt' will also use the
   // correct DataLayout if it is run on a pexe.
   M->setDataLayout("e-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-"
                    "f32:32:32-f64:64:64-p:32:32:32-v128:32:32");
 
-  if (InitStream()) return Error(Header.Unsupported());
+  if (InitStream()) return true; // InitSream will set the error string.
 
   // We expect a number of well-defined blocks, though we don't necessarily
   // need to understand them all.
   while (1) {
     if (Stream.AtEndOfStream())
       return false;
 
     NaClBitstreamEntry Entry =
       Stream.advance(NaClBitstreamCursor::AF_DontAutoprocessAbbrevs);
 
@@ skipping 754 matching lines @@
 }
 
 bool NaClBitcodeReader::InitStreamFromBuffer() {
   const unsigned char *BufPtr = (const unsigned char*)Buffer->getBufferStart();
   const unsigned char *BufEnd = BufPtr+Buffer->getBufferSize();
 
   if (Buffer->getBufferSize() & 3)
     return Error("Bitcode stream should be a multiple of 4 bytes in length");
 
   if (Header.Read(BufPtr, BufEnd))
-    return Error("Invalid PNaCl bitcode header");
+    return Error(Header.Unsupported());
 
   StreamFile.reset(new NaClBitstreamReader(BufPtr, BufEnd));
   Stream.init(*StreamFile);
 
-  return AcceptHeader();
+  if (AcceptHeader())
+    return Error(Header.Unsupported());
+  return false;
 }
 
 bool NaClBitcodeReader::InitLazyStream() {
   StreamingMemoryObject *Bytes = new StreamingMemoryObject(LazyStreamer);
   if (Header.Read(Bytes))
-    return Error("Invalid PNaCl bitcode header");
+    return Error(Header.Unsupported());
 
   StreamFile.reset(new NaClBitstreamReader(Bytes, Header.getHeaderSize()));
   Stream.init(*StreamFile);
-  return AcceptHeader();
+  if (AcceptHeader())
+    return Error(Header.Unsupported());
+  return false;
 }
 
 //===----------------------------------------------------------------------===//
 // External interface
 //===----------------------------------------------------------------------===//
 
 /// getNaClLazyBitcodeModule - lazy function-at-a-time loading from a file.
 ///
 Module *llvm::getNaClLazyBitcodeModule(MemoryBuffer *Buffer,
                                        LLVMContext& Context,
@@ skipping 54 matching lines @@
   if (M->MaterializeAllPermanently(ErrMsg)) {
     delete M;
     return 0;
   }
 
   // TODO: Restore the use-lists to the in-memory state when the bitcode was
   // written.  We must defer until the Module has been fully materialized.
 
   return M;
 }