diff --git a/llvm/test/tools/llvm-nm/XCOFF/Inputs/test_xlclang.o b/llvm/test/tools/llvm-nm/XCOFF/Inputs/test_xlclang.o
new file mode 100644
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000
GIT binary patch
literal 0
Hc$@<O00001

literal 0
Hc$@<O00001

diff --git a/llvm/test/tools/llvm-nm/XCOFF/basic.test b/llvm/test/tools/llvm-nm/XCOFF/basic.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-nm/XCOFF/basic.test
@@ -0,0 +1,30 @@
+## Test llvm-nm for XCOFF object files.
+# RUN: llvm-nm  %p/Inputs/test_xlclang.o | FileCheck --check-prefix=NM-SYM %s
+
+## test_xlclang.o is generated by the following source compiled with IBM xlclang++ in aix os.   
+## int value = 0;
+##
+## __attribute__ ((weak))  int weak_value = 5;
+##
+## static int func0 () {
+##   return value;
+## }
+##
+## int func1 (int i) {
+##   return func0() * i;
+## }
+
+# NM-SYM:      00000000 t
+# NM-SYM-NEXT: 00000040 T ._Z5func1i
+# NM-SYM-NEXT: 00000000 t ._ZL5func0v
+# NM-SYM-NEXT: 00000120 b .bss
+# NM-SYM-NEXT: 00000100 d .data
+# NM-SYM-NEXT: 00000000 f .file
+# NM-SYM-NEXT: 00000000 t .text
+
+# NM-SYM:      00000104 d _Z5func1i
+# NM-SYM-NEXT: 0000010c D _Z5func1i
+# NM-SYM-NEXT: 00000100 d value
+# NM-SYM-NEXT: 00000118 D value
+# NM-SYM-NEXT: 00000108 d weak_value
+# NM-SYM-NEXT: 0000011c W weak_value
diff --git a/llvm/test/tools/llvm-nm/XCOFF/invalid-section-index.test b/llvm/test/tools/llvm-nm/XCOFF/invalid-section-index.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-nm/XCOFF/invalid-section-index.test
@@ -0,0 +1,20 @@
+## Test the behavior of the symbol reference section.
+
+# RUN: yaml2obj --docnum=1 %s -o %t.o
+# RUN: llvm-nm %t.o 2>&1 | FileCheck %s -DFILE=%t.o --check-prefix=NM
+
+# NM:      {{.*}}llvm-nm{{(\.exe)?}}: warning: [[FILE]]: for symbol with index 0: the section index (4) is invalid
+# NM-NEXT: 00000000 ? .text 
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: 0x1DF
+Sections:
+  - Name: .text
+Symbols:
+  - Name:               .text
+    Value:              0x0
+    SectionIndex: 4
+    Type:               0x0
+    StorageClass:       C_STAT
+    NumberOfAuxEntries: 1
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
@@ -31,6 +31,7 @@
 #include "llvm/Object/TapiFile.h"
 #include "llvm/Object/TapiUniversal.h"
 #include "llvm/Object/Wasm.h"
+#include "llvm/Object/XCOFFObjectFile.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/Option.h"
@@ -127,6 +128,20 @@
 
 static StringRef ToolName;
 
+static void warn(Error Err, Twine Path, Twine Context = Twine()) {
+  assert(Err);
+
+  // Flush the standard output so that the warning isn't interleaved with other
+  // output if stdout and stderr are writing to the same place.
+  outs().flush();
+
+  handleAllErrors(std::move(Err), [&](const ErrorInfoBase &EI) {
+    WithColor::warning(errs(), ToolName)
+        << Path << ": " << (Context.str().empty() ? "" : Context + ": ")
+        << EI.message() << "\n";
+  });
+}
+
 static void error(Twine Message, Twine Path = Twine()) {
   HadError = true;
   WithColor::error(errs(), ToolName) << Path << ": " << Message << "\n";
@@ -246,6 +261,9 @@
     return Triple(IRObj->getTargetTriple()).isArch64Bit();
   if (isa<COFFObjectFile>(Obj) || isa<COFFImportFile>(Obj))
     return false;
+  if (XCOFFObjectFile *XCOFFObj = dyn_cast<XCOFFObjectFile>(&Obj))
+    return XCOFFObj->is64Bit();
+
   if (isa<WasmObjectFile>(Obj))
     return false;
   if (TapiFile *Tapi = dyn_cast<TapiFile>(&Obj))
@@ -903,6 +921,43 @@
   return '?';
 }
 
+static char getSymbolNMTypeChar(XCOFFObjectFile &Obj, symbol_iterator I) {
+  Expected<uint32_t> TypeOrErr = I->getType();
+  if (!TypeOrErr) {
+
+    warn(TypeOrErr.takeError(), Obj.getFileName(),
+         "for symbol with index " +
+             Twine(Obj.getSymbolIndex(I->getRawDataRefImpl().p)));
+    return '?';
+  }
+
+  uint32_t SymType = *TypeOrErr;
+
+  if (SymType == SymbolRef::ST_Debug)
+    return 'N';
+
+  if (SymType == SymbolRef::ST_File)
+    return 'f';
+
+  // If the I->getSection() call would return an error, the earlier I->getType()
+  // call will already have returned the same error first.
+  section_iterator SecIter = cantFail(I->getSection());
+
+  if (SecIter == Obj.section_end())
+    return '?';
+
+  if (SecIter->isText())
+    return 't';
+
+  if (SecIter->isData())
+    return 'd';
+
+  if (SecIter->isBSS())
+    return 'b';
+
+  return '?';
+}
+
 static char getSymbolNMTypeChar(COFFImportFile &Obj) {
   switch (Obj.getCOFFImportHeader()->getType()) {
   case COFF::IMPORT_CODE:
@@ -1051,6 +1106,8 @@
     Ret = getSymbolNMTypeChar(*IR, I);
   else if (COFFObjectFile *COFF = dyn_cast<COFFObjectFile>(&Obj))
     Ret = getSymbolNMTypeChar(*COFF, I);
+  else if (XCOFFObjectFile *XCOFF = dyn_cast<XCOFFObjectFile>(&Obj))
+    Ret = getSymbolNMTypeChar(*XCOFF, I);
   else if (COFFImportFile *COFFImport = dyn_cast<COFFImportFile>(&Obj))
     Ret = getSymbolNMTypeChar(*COFFImport);
   else if (MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(&Obj))