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

llvm-svn: 298322

2 files changed, 9 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DIEHash.cpp b/llvm/lib/CodeGen/AsmPrinter/DIEHash.cpp
index d8ecc7ccfb9..8e3b88d0af0 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DIEHash.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DIEHash.cpp
@@ -490,9 +490,9 @@ uint64_t DIEHash::computeCUSignature(const DIE &Die) {
   Hash.final(Result);
 
   // ... take the least significant 8 bytes and return those. Our MD5
-  // implementation always returns its results in little endian, swap bytes
-  // appropriately.
-  return support::endian::read64le(Result + 8);
+  // implementation always returns its results in little endian, so we actually
+  // need the "high" word.
+  return Result.high();
 }
 
 /// This is based on the type signature computation given in section 7.27 of the
@@ -514,7 +514,7 @@ uint64_t DIEHash::computeTypeSignature(const DIE &Die) {
   Hash.final(Result);
 
   // ... take the least significant 8 bytes and return those. Our MD5
-  // implementation always returns its results in little endian, swap bytes
-  // appropriately.
-  return support::endian::read64le(Result + 8);
+  // implementation always returns its results in little endian, so we actually
+  // need the "high" word.
+  return Result.high();
 }
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 0b9bacd86e5..15e5be2e65d 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -39,7 +39,6 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Dwarf.h"
-#include "llvm/Support/Endian.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FormattedStream.h"
 #include "llvm/Support/LEB128.h"
@@ -1945,11 +1944,11 @@ uint64_t DwarfDebug::makeTypeSignature(StringRef Identifier) {
   MD5 Hash;
   Hash.update(Identifier);
   // ... take the least significant 8 bytes and return those. Our MD5
-  // implementation always returns its results in little endian, swap bytes
-  // appropriately.
+  // implementation always returns its results in little endian, so we actually
+  // need the "high" word.
   MD5::MD5Result Result;
   Hash.final(Result);
-  return support::endian::read64le(Result + 8);
+  return Result.high();
 }
 
 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,