Subzero: Switch file reading to be based on a DataStreamer and MemoryObject.

src/PNaClTranslator.cpp

 //===- subzero/src/PNaClTranslator.cpp - ICE from bitcode -----------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the PNaCl bitcode file to Ice, to machine code
@@ skipping 2974 matching lines @@
   }
   // Generate error message by using default block implementation.
   BlockParserBaseClass Parser(BlockID, this);
   return Parser.ParseThisBlock();
 }
 
 } // end of anonymous namespace
 
 namespace Ice {
 
-void PNaClTranslator::translate(const std::string &IRFilename) {
-  ErrorOr<std::unique_ptr<MemoryBuffer>> ErrOrFile =
-      MemoryBuffer::getFileOrSTDIN(IRFilename);
-  if (std::error_code EC = ErrOrFile.getError()) {
-    errs() << "Error reading '" << IRFilename << "': " << EC.message() << "\n";
-    ErrorStatus.assign(EC.value());
-    return;
-  }
-
-  std::unique_ptr<MemoryBuffer> MemBuf(ErrOrFile.get().release());
-  translateBuffer(IRFilename, MemBuf.get());
+void PNaClTranslator::translateBuffer(const std::string &IRFilename,

[Derek Schuff, 2015/03/06 21:56:05]

so is translatebuffer still used now that it's not used by translate()?

[jvoung (off chromium), 2015/03/06 22:34:53]

translateBuffer is being used by:

subzero/unittest/BitcodeMunge.cpp:  Translator.translateBuffer(TestName,
MungedInput.get());

+                                      MemoryBuffer *MemBuf) {
+  std::unique_ptr<MemoryObject> MemObj(getNonStreamedMemoryObject(
+      reinterpret_cast<const unsigned char *>(MemBuf->getBufferStart()),
+      reinterpret_cast<const unsigned char *>(MemBuf->getBufferEnd())));
+  translate(IRFilename, std::move(MemObj));
 }
 
-void PNaClTranslator::translateBuffer(const std::string &IRFilename,
-                                      MemoryBuffer *MemBuf) {
-  if (MemBuf->getBufferSize() % 4 != 0) {
-    errs() << IRFilename
-           << ": Bitcode stream should be a multiple of 4 bytes in length.\n";
-    ErrorStatus.assign(EC_Bitcode);
-    return;
-  }
-
-  const unsigned char *BufPtr = (const unsigned char *)MemBuf->getBufferStart();
-  const unsigned char *HeaderPtr = BufPtr;
-  const unsigned char *EndBufPtr = BufPtr + MemBuf->getBufferSize();
+void PNaClTranslator::translate(const std::string &IRFilename,
+                                std::unique_ptr<MemoryObject> &&MemObj) {
 
   // Read header and verify it is good.
   NaClBitcodeHeader Header;
-  if (Header.Read(HeaderPtr, EndBufPtr) || !Header.IsSupported()) {
+  if (Header.Read(MemObj.get()) || !Header.IsSupported()) {
     errs() << "Invalid PNaCl bitcode header.\n";
     ErrorStatus.assign(EC_Bitcode);
     return;
   }
 
   // Create a bitstream reader to read the bitcode file.
-  NaClBitstreamReader InputStreamFile(BufPtr, EndBufPtr,
-                                      Header.getHeaderSize());
+  NaClBitstreamReader InputStreamFile(MemObj.release(), Header.getHeaderSize());
   NaClBitstreamCursor InputStream(InputStreamFile);
 
   TopLevelParser Parser(*this, InputStream, ErrorStatus);
   int TopLevelBlocks = 0;
   while (!InputStream.AtEndOfStream()) {
     if (Parser.Parse()) {
       ErrorStatus.assign(EC_Bitcode);
       return;
     }
     ++TopLevelBlocks;
   }
 
   if (TopLevelBlocks != 1) {
     errs() << IRFilename
            << ": Contains more than one module. Found: " << TopLevelBlocks
            << "\n";
     ErrorStatus.assign(EC_Bitcode);
   }
+  if (InputStreamFile.getBitcodeBytes().getExtent() % 4 != 0) {
+    errs() << IRFilename
+           << ": Bitcode stream should be a multiple of 4 bytes in length.\n";
+    ErrorStatus.assign(EC_Bitcode);
+    return;
+  }
 }
 
 } // end of namespace Ice