[pr21886] Change MCJIT/ELF to support MSVC C++ mangled symbol.

[oota-llvm.git] / lib / Object / ELFObjectFile.cpp

diff --git a/lib/Object/ELFObjectFile.cpp b/lib/Object/ELFObjectFile.cpp
index ab5f8108af13a4edde11e06aa8235f60d15df098..8ccb2538ac78d06abb8a13b194f1e4eeb4b1357a 100644 (file)
--- a/lib/Object/ELFObjectFile.cpp
+++ b/lib/Object/ELFObjectFile.cpp
@@ -11,40 +11,71 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Object/ELF.h"
+#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Support/MathExtras.h"
 
 namespace llvm {
-
 using namespace object;
 
-namespace {
-  std::pair<unsigned char, unsigned char>
-  getElfArchType(MemoryBuffer *Object) {
-    if (Object->getBufferSize() < ELF::EI_NIDENT)
-      return std::make_pair((uint8_t)ELF::ELFCLASSNONE,(uint8_t)ELF::ELFDATANONE);
-    return std::make_pair( (uint8_t)Object->getBufferStart()[ELF::EI_CLASS]
-                         , (uint8_t)Object->getBufferStart()[ELF::EI_DATA]);
-  }
-}
+ELFObjectFileBase::ELFObjectFileBase(unsigned int Type, MemoryBufferRef Source)
+    : ObjectFile(Type, Source) {}
 
-// Creates an in-memory object-file by default: createELFObjectFile(Buffer)
-ObjectFile *ObjectFile::createELFObjectFile(MemoryBuffer *Object) {
-  std::pair<unsigned char, unsigned char> Ident = getElfArchType(Object);
-  error_code ec;
+ErrorOr<std::unique_ptr<ObjectFile>>
+ObjectFile::createELFObjectFile(MemoryBufferRef Obj) {
+  std::pair<unsigned char, unsigned char> Ident =
+      getElfArchType(Obj.getBuffer());
+  std::size_t MaxAlignment =
+      1ULL << countTrailingZeros(uintptr_t(Obj.getBufferStart()));
 
+  std::error_code EC;
+  std::unique_ptr<ObjectFile> R;
   if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB)
-    return new ELFObjectFile<support::little, false>(Object, ec);
+#if !LLVM_IS_UNALIGNED_ACCESS_FAST
+    if (MaxAlignment >= 4)
+      R.reset(new ELFObjectFile<ELFType<support::little, 4, false>>(Obj, EC));
+    else
+#endif
+    if (MaxAlignment >= 2)
+      R.reset(new ELFObjectFile<ELFType<support::little, 2, false>>(Obj, EC));
+    else
+      return object_error::parse_failed;
   else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB)
-    return new ELFObjectFile<support::big, false>(Object, ec);
+#if !LLVM_IS_UNALIGNED_ACCESS_FAST
+    if (MaxAlignment >= 4)
+      R.reset(new ELFObjectFile<ELFType<support::big, 4, false>>(Obj, EC));
+    else
+#endif
+    if (MaxAlignment >= 2)
+      R.reset(new ELFObjectFile<ELFType<support::big, 2, false>>(Obj, EC));
+    else
+      return object_error::parse_failed;
   else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB)
-    return new ELFObjectFile<support::big, true>(Object, ec);
+#if !LLVM_IS_UNALIGNED_ACCESS_FAST
+    if (MaxAlignment >= 8)
+      R.reset(new ELFObjectFile<ELFType<support::big, 8, true>>(Obj, EC));
+    else
+#endif
+    if (MaxAlignment >= 2)
+      R.reset(new ELFObjectFile<ELFType<support::big, 2, true>>(Obj, EC));
+    else
+      return object_error::parse_failed;
   else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) {
-    ELFObjectFile<support::little, true> *result =
-          new ELFObjectFile<support::little, true>(Object, ec);
-    return result;
+#if !LLVM_IS_UNALIGNED_ACCESS_FAST
+    if (MaxAlignment >= 8)
+      R.reset(new ELFObjectFile<ELFType<support::little, 8, true>>(Obj, EC));
+    else
+#endif
+    if (MaxAlignment >= 2)
+      R.reset(new ELFObjectFile<ELFType<support::little, 2, true>>(Obj, EC));
+    else
+      return object_error::parse_failed;
   }
+  else
+    llvm_unreachable("Buffer is not an ELF object file!");
 
-  report_fatal_error("Buffer is not an ELF object file!");
+  if (EC)
+    return EC;
+  return std::move(R);
 }
 
 } // end namespace llvm