DWARF parser: Use ArrayRef to represent form sizes and simplify DWARFDIE::extractFast() interface. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193560 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/DebugInfo/DWARFFormValue.cpp b/lib/DebugInfo/DWARFFormValue.cpp
index 1a59dd8..b07f275 100644
--- a/lib/DebugInfo/DWARFFormValue.cpp
+++ b/lib/DebugInfo/DWARFFormValue.cpp
@@ -62,8 +62,8 @@
   return (Version == 2) ? AddrSize : 4;
 }
 
-const uint8_t *
-DWARFFormValue::getFixedFormSizes(uint8_t AddrSize, uint16_t Version) {
+ArrayRef<uint8_t> DWARFFormValue::getFixedFormSizes(uint8_t AddrSize,
+                                                    uint16_t Version) {
   uint8_t RefAddrSize = getRefAddrSize(AddrSize, Version);
   if (AddrSize == 4 && RefAddrSize == 4)
     return FixedFormSizes<4, 4>::sizes;
@@ -73,7 +73,7 @@
     return FixedFormSizes<8, 4>::sizes;
   if (AddrSize == 8 && RefAddrSize == 8)
     return FixedFormSizes<8, 8>::sizes;
-  return 0;
+  return None;
 }
 
 static const DWARFFormValue::FormClass DWARF4FormClasses[] = {