3 files changed, 20 insertions, 17 deletions
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index f5f36e461f..c880707949 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -1250,24 +1250,25 @@ void CompileUnit::constructSubrangeDIE(DIE &Buffer, DISubrange SR,
                                        DIE *IndexTy) {
   DIE *DW_Subrange = new DIE(dwarf::DW_TAG_subrange_type);
   addDIEEntry(DW_Subrange, dwarf::DW_AT_type, dwarf::DW_FORM_ref4, IndexTy);
+
+  // The L value defines the lower bounds which is typically zero for C/C++. The
+  // Count value is the number of elements.  Values are 64 bit. If Count == -1
+  // then the array is unbounded and we do not emit DW_AT_lower_bound and
+  // DW_AT_upper_bound attributes. If L == 0 and Count == 0, then the array has
+  // zero elements in which case we do not emit an upper bound.
   uint64_t L = SR.getLo();
-  uint64_t H = SR.getHi();
   int64_t Count = SR.getCount();
 
-  // The L value defines the lower bounds which is typically zero for C/C++. The
-  // H value is the upper bounds.  Values are 64 bit.  H - L + 1 is the size
-  // of the array. If L > H then do not emit DW_AT_lower_bound and
-  // DW_AT_upper_bound attributes. If L is zero and H is also zero then the
-  // array has one element and in such case do not emit lower bound.
+  if (Count != -1) {
+    // FIXME: An unbounded array should reference the expression that defines
+    // the array.
+    if (L)
+      addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, 0, L);
 
-  if (L > H) {
-    Buffer.addChild(DW_Subrange);
-    return;
+    if (Count != 0)
+      addUInt(DW_Subrange, dwarf::DW_AT_upper_bound, 0, Count - 1);
   }
-  if (L)
-    addUInt(DW_Subrange, dwarf::DW_AT_lower_bound, 0, L);
-  if (H > 0 || Count != 0)
-    addUInt(DW_Subrange, dwarf::DW_AT_upper_bound, 0, H);
+
   Buffer.addChild(DW_Subrange);
 }
 
diff --git a/lib/VMCore/DIBuilder.cpp b/lib/VMCore/DIBuilder.cpp
index 2b77edc7f9..b3bbde86c5 100644
--- a/lib/VMCore/DIBuilder.cpp
+++ b/lib/VMCore/DIBuilder.cpp
@@ -741,12 +741,10 @@ DIArray DIBuilder::getOrCreateArray(ArrayRef<Value *> Elements) {
 
 /// getOrCreateSubrange - Create a descriptor for a value range.  This
 /// implicitly uniques the values returned.
-DISubrange DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Hi,
-                                          int64_t Count) {
+DISubrange DIBuilder::getOrCreateSubrange(int64_t Lo, int64_t Count) {
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subrange_type),
     ConstantInt::get(Type::getInt64Ty(VMContext), Lo),
-    ConstantInt::get(Type::getInt64Ty(VMContext), Hi),
     ConstantInt::get(Type::getInt64Ty(VMContext), Count)
   };
 
diff --git a/lib/VMCore/DebugInfo.cpp b/lib/VMCore/DebugInfo.cpp
index 73eb92ee84..0b43cc0beb 100644
--- a/lib/VMCore/DebugInfo.cpp
+++ b/lib/VMCore/DebugInfo.cpp
@@ -1049,7 +1049,11 @@ void DIDescriptor::print(raw_ostream &OS) const {
 }
 
 void DISubrange::printInternal(raw_ostream &OS) const {
-  OS << " [" << getLo() << ", " << getHi() << ']';
+  int64_t Count = getCount();
+  if (Count != -1)
+    OS << " [" << getLo() << ", " << Count - 1 << ']';
+  else
+    OS << " [unbound]";
 }
 
 void DIScope::printInternal(raw_ostream &OS) const {