diff --git a/llvm/test/tools/llvm-nm/XCOFF/demangle.test b/llvm/test/tools/llvm-nm/XCOFF/demangle.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-nm/XCOFF/demangle.test
@@ -0,0 +1,57 @@
+## Test llvm-nm demangle symbols for XCOFF object files.
+# RUN: llvm-nm  --demangle %p/Inputs/test_gcc.o | FileCheck --check-prefix=NM-DEMANGLE %s
+
+## test_gcc.o is generated by the following source compiled with g++ in aix os.   
+##  int v = 0;
+## 
+## __attribute__((visibility ("protected"))) int  vp = 1;
+## __attribute__((visibility ("hidden"))) int  vh = 2;
+## __attribute__((visibility ("default"))) int  vd = 3;
+## __attribute__ ((weak)) __attribute__((visibility ("hidden"))) int vwh = 4;
+## __attribute__ ((weak)) __attribute__((visibility ("protected"))) int vwp = 5;
+## 
+## class C {
+## public:
+##  int c;
+##  C(int v):c(v) {}
+## };
+## 
+## C cc(2);
+## 
+## static int si = 6;
+## 
+## static int func0 () {
+##   return vp+si;
+## }
+## 
+## int func1 (int i) {
+##   return func0() * i;
+## }
+## 
+## __attribute__ ((weak)) __attribute__((visibility ("hidden")))
+## int fwh() {
+##   return si+1;
+## }
+## 
+## __attribute__ ((weak)) __attribute__((visibility ("protected")))
+## int fwp() {
+##   return si+2;
+## }
+
+# NM-DEMANGLE:      000001e4 t ._GLOBAL__sub_I_v
+# NM-DEMANGLE-NEXT: 000000b0 W .fwh()
+# NM-DEMANGLE-NEXT: 000000f4 W .fwp()
+# NM-DEMANGLE-NEXT: 00000138 t .__static_initialization_and_destruction_0(int, int)
+# NM-DEMANGLE-NEXT: 00000050 T .func1(int)
+# NM-DEMANGLE-NEXT: 00000000 t .func0()
+# NM-DEMANGLE-NEXT: 00000294 W .C::C(int)
+# NM-DEMANGLE-NEXT: 00000294 t .C::C(int)
+# NM-DEMANGLE:      00000360 d _GLOBAL__sub_I_v
+# NM-DEMANGLE-NEXT: 0000033c W fwh()
+# NM-DEMANGLE-NEXT: 00000348 W fwp()
+# NM-DEMANGLE-NEXT: 00000354 d __static_initialization_and_destruction_0(int, int)
+# NM-DEMANGLE-NEXT: 00000330 D func1(int)
+# NM-DEMANGLE-NEXT: 00000330 d func1(int)
+# NM-DEMANGLE-NEXT: 0000037c d si
+# NM-DEMANGLE-NEXT: 00000324 d func0()
+# NM-DEMANGLE-NEXT: 00000310 W C::C(int)
diff --git a/llvm/tools/llvm-nm/llvm-nm.cpp b/llvm/tools/llvm-nm/llvm-nm.cpp
--- a/llvm/tools/llvm-nm/llvm-nm.cpp
+++ b/llvm/tools/llvm-nm/llvm-nm.cpp
@@ -617,10 +617,7 @@
     outs() << format("   %02x", NType);
 }
 
-static Optional<std::string> demangle(StringRef Name, bool StripUnderscore) {
-  if (StripUnderscore && !Name.empty() && Name[0] == '_')
-    Name = Name.substr(1);
-
+static Optional<std::string> demangle(StringRef Name) {
   if (!Name.startswith("_Z"))
     return None;
 
@@ -635,6 +632,23 @@
   return S;
 }
 
+static Optional<std::string> demangleXCOFF(StringRef Name) {
+
+  if (!Name.empty() && Name[0] == '.')
+    Name = Name.substr(1);
+  else
+    return demangle(Name);
+
+  Optional<std::string> Opt = demangle(Name);
+  return (Opt ? "." + *Opt : None);
+}
+
+static Optional<std::string> demangleMachO(StringRef Name) {
+  if (!Name.empty() && Name[0] == '_')
+    Name = Name.substr(1);
+  return demangle(Name);
+}
+
 static bool symbolIsDefined(const NMSymbol &Sym) {
   return Sym.TypeChar != 'U' && Sym.TypeChar != 'w' && Sym.TypeChar != 'v';
 }
@@ -723,7 +737,12 @@
     std::string Name = S.Name;
     MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(&Obj);
     if (Demangle) {
-      if (Optional<std::string> Opt = demangle(S.Name, MachO))
+      Optional<std::string> (*Fn)(StringRef Name) = demangle;
+      if (Obj.isXCOFF())
+        Fn = demangleXCOFF;
+      if (Obj.isMachO())
+        Fn = demangleMachO;
+      if (Optional<std::string> Opt = Fn(S.Name))
         Name = *Opt;
     }
     if (S.Sym.getRawDataRefImpl().p) {