[Object] Change ObjectFile::getSectionContents to return Expected<ArrayRef<uint8_t>>

Change
std::error_code getSectionContents(DataRefImpl, StringRef &) const;
to
Expected<ArrayRef<uint8_t>> getSectionContents(DataRefImpl) const;

Many object formats use ArrayRef<uint8_t> as the underlying type, which
is generally better than StringRef to represent binary data, so change
the type to decrease the number of type conversions.

Reviewed By: ruiu, sbc100

Differential Revision: https://reviews.llvm.org/D61781

llvm-svn: 360648

1 files changed, 10 insertions, 11 deletions

diff --git a/llvm/lib/Object/COFFObjectFile.cpp b/llvm/lib/Object/COFFObjectFile.cpp
index ccb861cb187..854664e679d 100644
--- a/llvm/lib/Object/COFFObjectFile.cpp
+++ b/llvm/lib/Object/COFFObjectFile.cpp
@@ -292,13 +292,13 @@ uint64_t COFFObjectFile::getSectionSize(DataRefImpl Ref) const {
   return getSectionSize(toSec(Ref));
 }
 
-std::error_code COFFObjectFile::getSectionContents(DataRefImpl Ref,
-                                                   StringRef &Result) const {
+Expected<ArrayRef<uint8_t>>
+COFFObjectFile::getSectionContents(DataRefImpl Ref) const {
   const coff_section *Sec = toSec(Ref);
   ArrayRef<uint8_t> Res;
-  std::error_code EC = getSectionContents(Sec, Res);
-  Result = StringRef(reinterpret_cast<const char*>(Res.data()), Res.size());
-  return EC;
+  if (Error E = getSectionContents(Sec, Res))
+    return std::move(E);
+  return Res;
 }
 
 uint64_t COFFObjectFile::getSectionAlignment(DataRefImpl Ref) const {
@@ -1118,22 +1118,21 @@ uint64_t COFFObjectFile::getSectionSize(const coff_section *Sec) const {
   return Sec->SizeOfRawData;
 }
 
-std::error_code
-COFFObjectFile::getSectionContents(const coff_section *Sec,
-                                   ArrayRef<uint8_t> &Res) const {
+Error COFFObjectFile::getSectionContents(const coff_section *Sec,
+                                         ArrayRef<uint8_t> &Res) const {
   // In COFF, a virtual section won't have any in-file
   // content, so the file pointer to the content will be zero.
   if (Sec->PointerToRawData == 0)
-    return std::error_code();
+    return Error::success();
   // The only thing that we need to verify is that the contents is contained
   // within the file bounds. We don't need to make sure it doesn't cover other
   // data, as there's nothing that says that is not allowed.
   uintptr_t ConStart = uintptr_t(base()) + Sec->PointerToRawData;
   uint32_t SectionSize = getSectionSize(Sec);
   if (checkOffset(Data, ConStart, SectionSize))
-    return object_error::parse_failed;
+    return make_error<BinaryError>();
   Res = makeArrayRef(reinterpret_cast<const uint8_t *>(ConStart), SectionSize);
-  return std::error_code();
+  return Error::success();
 }
 
 const coff_relocation *COFFObjectFile::toRel(DataRefImpl Rel) const {