r298322 - Add a function to MD5 a file's contents.

[Zachary Turner via cfe-commits]

Author: zturner
Date: Mon Mar 20 18:33:18 2017
New Revision: 298322

URL: http://llvm.org/viewvc/llvm-project?rev=298322&view=rev
Log:
Add a function to MD5 a file's contents.

In doing so, clean up the MD5 interface a little.  Most
existing users only care about the lower 8 bytes of an MD5,
but for some users that care about the upper and lower,
there wasn't a good interface.  Furthermore, consumers
of the MD5 checksum were required to handle endianness
details on their own, so it seems reasonable to abstract
this into a nicer interface that just gives you the right
value.

Differential Revision: https://reviews.llvm.org/D31105

Modified:
    cfe/trunk/lib/CodeGen/CodeGenPGO.cpp
    cfe/trunk/lib/Frontend/ASTUnit.cpp

Modified: cfe/trunk/lib/CodeGen/CodeGenPGO.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenPGO.cpp?rev=298322&r1=298321&r2=298322&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenPGO.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenPGO.cpp Mon Mar 20 18:33:18 2017
@@ -612,7 +612,7 @@ uint64_t PGOHash::finalize() {
   llvm::MD5::MD5Result Result;
   MD5.final(Result);
   using namespace llvm::support;
-  return endian::read<uint64_t, little, unaligned>(Result);
+  return Result.low();
 }
 
 void CodeGenPGO::assignRegionCounters(GlobalDecl GD, llvm::Function *Fn) {

Modified: cfe/trunk/lib/Frontend/ASTUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/ASTUnit.cpp?rev=298322&r1=298321&r2=298322&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/ASTUnit.cpp (original)
+++ cfe/trunk/lib/Frontend/ASTUnit.cpp Mon Mar 20 18:33:18 2017
@@ -1252,7 +1252,7 @@ ASTUnit::PreambleFileHash::createForFile
   PreambleFileHash Result;
   Result.Size = Size;
   Result.ModTime = ModTime;
-  memset(Result.MD5, 0, sizeof(Result.MD5));
+  Result.MD5 = {};
   return Result;
 }
 
@@ -1273,7 +1273,7 @@ namespace clang {
 bool operator==(const ASTUnit::PreambleFileHash &LHS,
                 const ASTUnit::PreambleFileHash &RHS) {
   return LHS.Size == RHS.Size && LHS.ModTime == RHS.ModTime &&
-         memcmp(LHS.MD5, RHS.MD5, sizeof(LHS.MD5)) == 0;
+         LHS.MD5 == RHS.MD5;
 }
 } // namespace clang