Index: include/llvm/Object/Wasm.h
===================================================================
--- include/llvm/Object/Wasm.h
+++ include/llvm/Object/Wasm.h
@@ -183,7 +183,6 @@
   bool isSectionData(DataRefImpl Sec) const override;
   bool isSectionBSS(DataRefImpl Sec) const override;
   bool isSectionVirtual(DataRefImpl Sec) const override;
-  bool isSectionBitcode(DataRefImpl Sec) const override;
   relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
   relocation_iterator section_rel_end(DataRefImpl Sec) const override;
 
@@ -208,6 +207,10 @@
   const WasmSection &getWasmSection(DataRefImpl Ref) const;
   const wasm::WasmRelocation &getWasmRelocation(DataRefImpl Ref) const;
 
+  const wasm::WasmDataSegment &getWasmDataSegment(DataRefImpl Ref) const;
+
+  const ArrayRef<uint8_t> &getDataRefContent(DataRefImpl Ref) const;
+
   WasmSection* findCustomSectionByName(StringRef Name);
   WasmSection* findSectionByType(uint32_t Type);
 
@@ -261,7 +264,7 @@
   uint32_t ImportSection = 0;
   uint32_t ExportSection = 0;
 
-  StringMap<uint32_t> SymbolMap;
+  StringMap<uint32_t> SymbolMap;  
 };
 
 } // end namespace object
Index: lib/MC/WasmObjectWriter.cpp
===================================================================
--- lib/MC/WasmObjectWriter.cpp
+++ lib/MC/WasmObjectWriter.cpp
@@ -842,7 +842,13 @@
     write8(wasm::WASM_OPCODE_I32_CONST);
     encodeSLEB128(Segment.Offset, getStream()); // offset
     write8(wasm::WASM_OPCODE_END);
-    encodeULEB128(Segment.Data.size(), getStream()); // size
+
+    uint64_t Padding = OffsetToAlignment(getStream().tell() + 5, Segment.Alignment);
+    unsigned SizeLen = encodeULEB128(Segment.Data.size() + Padding, getStream(), 5); // size
+    assert(SizeLen == 5);
+    
+    WriteZeros(Padding);
+    assert(OffsetToAlignment(getStream().tell(), Segment.Alignment) == 0 && "DataSegments is not aligned");
     Segment.Section->setSectionOffset(getStream().tell() - Section.ContentsOffset);
     writeBytes(Segment.Data); // data
   }
Index: lib/Object/WasmObjectFile.cpp
===================================================================
--- lib/Object/WasmObjectFile.cpp
+++ lib/Object/WasmObjectFile.cpp
@@ -24,6 +24,7 @@
 #include "llvm/Support/Error.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/LEB128.h"
+#include "llvm/Support/MathExtras.h"
 #include <algorithm>
 #include <cassert>
 #include <cstdint>
@@ -982,7 +983,14 @@
   return section_iterator(SectionRef(Ref, this));
 }
 
-void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { Sec.d.a++; }
+void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { 
+  if (isSectionData(Sec) && Sec.d.b < DataSegments.size()) {
+      Sec.d.b++;
+  } else {
+      Sec.d.a++;
+      Sec.d.b = 0;
+  }
+}
 
 std::error_code WasmObjectFile::getSectionName(DataRefImpl Sec,
                                                StringRef &Res) const {
@@ -1002,7 +1010,11 @@
     ECase(START);
     ECase(ELEM);
     ECase(CODE);
-    ECase(DATA);
+  case wasm::WASM_SEC_DATA: {
+    const WasmSegment &Seg = DataSegments[Sec.d.b];
+    Res = Seg.Data.Name;
+    break;
+  }
   case wasm::WASM_SEC_CUSTOM:
     Res = S.Name;
     break;
@@ -1020,22 +1032,45 @@
 }
 
 uint64_t WasmObjectFile::getSectionSize(DataRefImpl Sec) const {
-  const WasmSection &S = Sections[Sec.d.a];
-  return S.Content.size();
+  return getDataRefContent(Sec).size();
 }
 
 std::error_code WasmObjectFile::getSectionContents(DataRefImpl Sec,
                                                    StringRef &Res) const {
-  const WasmSection &S = Sections[Sec.d.a];
-  // This will never fail since wasm sections can never be empty (user-sections
-  // must have a name and non-user sections each have a defined structure).
-  Res = StringRef(reinterpret_cast<const char *>(S.Content.data()),
-                  S.Content.size());
+
+  const ArrayRef<uint8_t> &Content = getDataRefContent(Sec); 
+
+  Res = StringRef(reinterpret_cast<const char *>(Content.data()),
+                  Content.size());
   return std::error_code();
 }
 
 uint64_t WasmObjectFile::getSectionAlignment(DataRefImpl Sec) const {
-  return 1;
+  if (isSectionData(Sec)) {
+    const wasm::WasmDataSegment &Data = getWasmDataSegment(Sec);
+    return Data.Alignment;
+  }
+
+  return 1;  
+}
+
+const wasm::WasmDataSegment &WasmObjectFile::getWasmDataSegment(DataRefImpl Sec) const {
+  assert(isSectionData(Sec) && "Section should be Data");
+  assert(Sec.d.b < DataSegments.size());
+  return DataSegments[Sec.d.b].Data;
+}
+
+const ArrayRef<uint8_t> &WasmObjectFile::getDataRefContent(DataRefImpl Sec) const {
+  if (isSectionData(Sec)) {
+    const wasm::WasmDataSegment &Data = getWasmDataSegment(Sec);
+    size_t Padding = alignmentAdjustment(Data.Content.data(), Data.Alignment);
+
+    ArrayRef<uint8_t> AdjustedContent(Data.Content.data() + Padding, Data.Content.size() - Padding);
+    return std::move(AdjustedContent);
+  }
+  // This will never fail since wasm sections can never be empty (user-sections
+  // must have a name and non-user sections each have a defined structure).
+  return getWasmSection(Sec).Content;
 }
 
 bool WasmObjectFile::isSectionCompressed(DataRefImpl Sec) const {
@@ -1054,8 +1089,6 @@
 
 bool WasmObjectFile::isSectionVirtual(DataRefImpl Sec) const { return false; }
 
-bool WasmObjectFile::isSectionBitcode(DataRefImpl Sec) const { return false; }
-
 relocation_iterator WasmObjectFile::section_rel_begin(DataRefImpl Ref) const {
   DataRefImpl RelocRef;
   RelocRef.d.a = Ref.d.a;
@@ -1113,6 +1146,7 @@
 section_iterator WasmObjectFile::section_begin() const {
   DataRefImpl Ref;
   Ref.d.a = 0;
+  Ref.d.b = 0;
   return section_iterator(SectionRef(Ref, this));
 }