[lld] r374148 - Unify the two CRC implementations

[Hans Wennborg via llvm-commits]

Author: hans
Date: Wed Oct  9 02:06:30 2019
New Revision: 374148

URL: http://llvm.org/viewvc/llvm-project?rev=374148&view=rev
Log:
Unify the two CRC implementations

David added the JamCRC implementation in r246590. More recently, Eugene
added a CRC-32 implementation in r357901, which falls back to zlib's
crc32 function if present.

These checksums are essentially the same, so having multiple
implementations seems unnecessary. This replaces the CRC-32
implementation with the simpler one from JamCRC, and implements the
JamCRC interface in terms of CRC-32 since this means it can use zlib's
implementation when available, saving a few bytes and potentially making
it faster.

JamCRC took an ArrayRef<char> argument, and CRC-32 took a StringRef.
This patch changes it to ArrayRef<uint8_t> which I think is the best
choice, and simplifies a few of the callers nicely.

Differential revision: https://reviews.llvm.org/D68570

Modified:
    lld/trunk/COFF/PDB.cpp

Modified: lld/trunk/COFF/PDB.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/COFF/PDB.cpp?rev=374148&r1=374147&r2=374148&view=diff
==============================================================================
--- lld/trunk/COFF/PDB.cpp (original)
+++ lld/trunk/COFF/PDB.cpp Wed Oct  9 02:06:30 2019
@@ -51,10 +51,10 @@
 #include "llvm/Object/COFF.h"
 #include "llvm/Object/CVDebugRecord.h"
 #include "llvm/Support/BinaryByteStream.h"
+#include "llvm/Support/CRC.h"
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/FormatVariadic.h"
-#include "llvm/Support/JamCRC.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include <memory>
@@ -965,9 +965,7 @@ static pdb::SectionContrib createSection
     sc.Imod = secChunk->file->moduleDBI->getModuleIndex();
     ArrayRef<uint8_t> contents = secChunk->getContents();
     JamCRC crc(0);
-    ArrayRef<char> charContents = makeArrayRef(
-        reinterpret_cast<const char *>(contents.data()), contents.size());
-    crc.update(charContents);
+    crc.update(contents);
     sc.DataCrc = crc.getCRC();
   } else {
     sc.Characteristics = os ? os->header.Characteristics : 0;