[OCaml] Fix ABI incompatibility

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

diff --git a/lib/Object/ELFObjectFile.cpp b/lib/Object/ELFObjectFile.cpp
index ab5f8108af13a4edde11e06aa8235f60d15df098..15bc6be0b46e7971dc3b7b60ac2f98010cbdf3a3 100644 (file)
--- a/lib/Object/ELFObjectFile.cpp
+++ b/lib/Object/ELFObjectFile.cpp
@@ -11,37 +11,60 @@
 //
 //===----------------------------------------------------------------------===//
 
-#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]);
-  }
-}
-
 // 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;
 
+  std::size_t MaxAlignment =
+    1ULL << countTrailingZeros(uintptr_t(Object->getBufferStart()));
+
   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)
+      return new ELFObjectFile<ELFType<support::little, 4, false> >(Object, ec);
+    else
+#endif
+    if (MaxAlignment >= 2)
+      return new ELFObjectFile<ELFType<support::little, 2, false> >(Object, ec);
+    else
+      llvm_unreachable("Invalid alignment for ELF file!");
   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)
+      return new ELFObjectFile<ELFType<support::big, 4, false> >(Object, ec);
+    else
+#endif
+    if (MaxAlignment >= 2)
+      return new ELFObjectFile<ELFType<support::big, 2, false> >(Object, ec);
+    else
+      llvm_unreachable("Invalid alignment for ELF file!");
   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)
+      return new ELFObjectFile<ELFType<support::big, 8, true> >(Object, ec);
+    else
+#endif
+    if (MaxAlignment >= 2)
+      return new ELFObjectFile<ELFType<support::big, 2, true> >(Object, ec);
+    else
+      llvm_unreachable("Invalid alignment for ELF file!");
   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)
+      return new ELFObjectFile<ELFType<support::little, 8, true> >(Object, ec);
+    else
+#endif
+    if (MaxAlignment >= 2)
+      return new ELFObjectFile<ELFType<support::little, 2, true> >(Object, ec);
+    else
+      llvm_unreachable("Invalid alignment for ELF file!");
   }
 
   report_fatal_error("Buffer is not an ELF object file!");