diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index f0058690e43dc..566affa91b769 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -256,6 +256,8 @@ static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
     return true;
   case Triple::ELF:
     return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
+  case Triple::GOFF:
+    llvm::report_fatal_error("ASan not implemented for GOFF");
   case Triple::XCOFF:
     llvm::report_fatal_error("ASan not implemented for XCOFF.");
   case Triple::Wasm:
diff --git a/clang/lib/CodeGen/CGObjCMac.cpp b/clang/lib/CodeGen/CGObjCMac.cpp
index 1d0379afb4b59..5922c63e01168 100644
--- a/clang/lib/CodeGen/CGObjCMac.cpp
+++ b/clang/lib/CodeGen/CGObjCMac.cpp
@@ -5106,9 +5106,10 @@ std::string CGObjCCommonMac::GetSectionName(StringRef Section,
            "expected the name to begin with __");
     return ("." + Section.substr(2) + "$B").str();
   case llvm::Triple::Wasm:
+  case llvm::Triple::GOFF:
   case llvm::Triple::XCOFF:
     llvm::report_fatal_error(
-        "Objective-C support is unimplemented for object file format.");
+        "Objective-C support is unimplemented for object file format");
   }
 
   llvm_unreachable("Unhandled llvm::Triple::ObjectFormatType enum");
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 67f06ac1c07c1..ff35d94626d1d 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -4915,6 +4915,8 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
   switch (Triple.getObjectFormat()) {
   case llvm::Triple::UnknownObjectFormat:
     llvm_unreachable("unknown file format");
+  case llvm::Triple::GOFF:
+    llvm_unreachable("GOFF is not yet implemented");
   case llvm::Triple::XCOFF:
     llvm_unreachable("XCOFF is not yet implemented");
   case llvm::Triple::COFF:
diff --git a/llvm/include/llvm/ADT/Triple.h b/llvm/include/llvm/ADT/Triple.h
index c578c097c6f64..7c3a4b2b699a7 100644
--- a/llvm/include/llvm/ADT/Triple.h
+++ b/llvm/include/llvm/ADT/Triple.h
@@ -173,6 +173,7 @@ class Triple {
     OpenBSD,
     Solaris,
     Win32,
+    ZOS,
     Haiku,
     Minix,
     RTEMS,
@@ -224,6 +225,7 @@ class Triple {
 
     COFF,
     ELF,
+    GOFF,
     MachO,
     Wasm,
     XCOFF,
@@ -468,6 +470,8 @@ class Triple {
     return getSubArch() == Triple::ARMSubArch_v7k;
   }
 
+  bool isOSzOS() const { return getOS() == Triple::ZOS; }
+
   /// isOSDarwin - Is this a "Darwin" OS (macOS, iOS, tvOS or watchOS).
   bool isOSDarwin() const {
     return isMacOSX() || isiOS() || isWatchOS();
@@ -620,6 +624,9 @@ class Triple {
     return getObjectFormat() == Triple::COFF;
   }
 
+  /// Tests whether the OS uses the GOFF binary format.
+  bool isOSBinFormatGOFF() const { return getObjectFormat() == Triple::GOFF; }
+
   /// Tests whether the environment is MachO.
   bool isOSBinFormatMachO() const {
     return getObjectFormat() == Triple::MachO;
diff --git a/llvm/include/llvm/Support/TargetRegistry.h b/llvm/include/llvm/Support/TargetRegistry.h
index d91eabae82357..2c65eb60f9109 100644
--- a/llvm/include/llvm/Support/TargetRegistry.h
+++ b/llvm/include/llvm/Support/TargetRegistry.h
@@ -510,6 +510,8 @@ class Target {
         S = createWasmStreamer(Ctx, std::move(TAB), std::move(OW),
                                std::move(Emitter), RelaxAll);
       break;
+    case Triple::GOFF:
+      report_fatal_error("GOFF MCObjectStreamer not implemented yet");
     case Triple::XCOFF:
       S = createXCOFFStreamer(Ctx, std::move(TAB), std::move(OW),
                               std::move(Emitter), RelaxAll);
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 7afef397e05ed..b6b2eb3b0dbed 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -4740,6 +4740,9 @@ static const char *getSectionNameForBitcode(const Triple &T) {
   case Triple::Wasm:
   case Triple::UnknownObjectFormat:
     return ".llvmbc";
+  case Triple::GOFF:
+    llvm_unreachable("GOFF is not yet implemented");
+    break;
   case Triple::XCOFF:
     llvm_unreachable("XCOFF is not yet implemented");
     break;
@@ -4756,6 +4759,9 @@ static const char *getSectionNameForCommandline(const Triple &T) {
   case Triple::Wasm:
   case Triple::UnknownObjectFormat:
     return ".llvmcmd";
+  case Triple::GOFF:
+    llvm_unreachable("GOFF is not yet implemented");
+    break;
   case Triple::XCOFF:
     llvm_unreachable("XCOFF is not yet implemented");
     break;
diff --git a/llvm/lib/MC/MCObjectFileInfo.cpp b/llvm/lib/MC/MCObjectFileInfo.cpp
index b77a9635f64c4..a400cc9de75cb 100644
--- a/llvm/lib/MC/MCObjectFileInfo.cpp
+++ b/llvm/lib/MC/MCObjectFileInfo.cpp
@@ -904,6 +904,9 @@ void MCObjectFileInfo::InitMCObjectFileInfo(const Triple &TheTriple, bool PIC,
     Env = IsWasm;
     initWasmMCObjectFileInfo(TT);
     break;
+  case Triple::GOFF:
+    report_fatal_error("Cannot initialize MC for GOFF object file format");
+    break;
   case Triple::XCOFF:
     Env = IsXCOFF;
     initXCOFFMCObjectFileInfo(TT);
@@ -923,6 +926,7 @@ MCSection *MCObjectFileInfo::getDwarfComdatSection(const char *Name,
   case Triple::MachO:
   case Triple::COFF:
   case Triple::Wasm:
+  case Triple::GOFF:
   case Triple::XCOFF:
   case Triple::UnknownObjectFormat:
     report_fatal_error("Cannot get DWARF comdat section for this object file "
diff --git a/llvm/lib/Support/Triple.cpp b/llvm/lib/Support/Triple.cpp
index 72648273b4cd5..7c2c44a538054 100644
--- a/llvm/lib/Support/Triple.cpp
+++ b/llvm/lib/Support/Triple.cpp
@@ -215,6 +215,7 @@ StringRef Triple::getOSTypeName(OSType Kind) {
   case WASI: return "wasi";
   case WatchOS: return "watchos";
   case Win32: return "windows";
+  case ZOS: return "zos";
   }
 
   llvm_unreachable("Invalid OSType");
@@ -499,6 +500,7 @@ static Triple::OSType parseOS(StringRef OSName) {
     .StartsWith("solaris", Triple::Solaris)
     .StartsWith("win32", Triple::Win32)
     .StartsWith("windows", Triple::Win32)
+    .StartsWith("zos", Triple::ZOS)
     .StartsWith("haiku", Triple::Haiku)
     .StartsWith("minix", Triple::Minix)
     .StartsWith("rtems", Triple::RTEMS)
@@ -552,6 +554,7 @@ static Triple::ObjectFormatType parseFormat(StringRef EnvironmentName) {
     .EndsWith("xcoff", Triple::XCOFF)
     .EndsWith("coff", Triple::COFF)
     .EndsWith("elf", Triple::ELF)
+    .EndsWith("goff", Triple::GOFF)
     .EndsWith("macho", Triple::MachO)
     .EndsWith("wasm", Triple::Wasm)
     .Default(Triple::UnknownObjectFormat);
@@ -643,6 +646,7 @@ static StringRef getObjectFormatTypeName(Triple::ObjectFormatType Kind) {
   case Triple::UnknownObjectFormat: return "";
   case Triple::COFF:  return "coff";
   case Triple::ELF:   return "elf";
+  case Triple::GOFF:  return "goff";
   case Triple::MachO: return "macho";
   case Triple::Wasm:  return "wasm";
   case Triple::XCOFF: return "xcoff";
@@ -700,7 +704,6 @@ static Triple::ObjectFormatType getDefaultFormat(const Triple &T) {
   case Triple::sparcv9:
   case Triple::spir64:
   case Triple::spir:
-  case Triple::systemz:
   case Triple::tce:
   case Triple::tcele:
   case Triple::thumbeb:
@@ -714,6 +717,11 @@ static Triple::ObjectFormatType getDefaultFormat(const Triple &T) {
       return Triple::XCOFF;
     return Triple::ELF;
 
+  case Triple::systemz:
+    if (T.isOSzOS())
+      return Triple::GOFF;
+    return Triple::ELF;
+
   case Triple::wasm32:
   case Triple::wasm64:
     return Triple::Wasm;
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 85ab19c20e84d..5d52a4b0fc187 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1950,9 +1950,10 @@ StringRef ModuleAddressSanitizer::getGlobalMetadataSection() const {
   case Triple::ELF:   return "asan_globals";
   case Triple::MachO: return "__DATA,__asan_globals,regular";
   case Triple::Wasm:
+  case Triple::GOFF:
   case Triple::XCOFF:
     report_fatal_error(
-        "ModuleAddressSanitizer not implemented for object file format.");
+        "ModuleAddressSanitizer not implemented for object file format");
   case Triple::UnknownObjectFormat:
     break;
   }
diff --git a/llvm/unittests/ADT/TripleTest.cpp b/llvm/unittests/ADT/TripleTest.cpp
index 1852d7b6a1b0d..1a6b0557bf50e 100644
--- a/llvm/unittests/ADT/TripleTest.cpp
+++ b/llvm/unittests/ADT/TripleTest.cpp
@@ -136,6 +136,18 @@ TEST(TripleTest, ParsedIDs) {
   EXPECT_EQ(Triple::FreeBSD, T.getOS());
   EXPECT_EQ(Triple::UnknownEnvironment, T.getEnvironment());
 
+  T = Triple("s390x-ibm-zos");
+  EXPECT_EQ(Triple::systemz, T.getArch());
+  EXPECT_EQ(Triple::IBM, T.getVendor());
+  EXPECT_EQ(Triple::ZOS, T.getOS());
+  EXPECT_EQ(Triple::UnknownEnvironment, T.getEnvironment());
+
+  T = Triple("systemz-ibm-zos");
+  EXPECT_EQ(Triple::systemz, T.getArch());
+  EXPECT_EQ(Triple::IBM, T.getVendor());
+  EXPECT_EQ(Triple::ZOS, T.getOS());
+  EXPECT_EQ(Triple::UnknownEnvironment, T.getEnvironment());
+
   T = Triple("arm-none-none-eabi");
   EXPECT_EQ(Triple::arm, T.getArch());
   EXPECT_EQ(Triple::UnknownVendor, T.getVendor());
@@ -1314,6 +1326,15 @@ TEST(TripleTest, FileFormat) {
   EXPECT_EQ(Triple::ELF, Triple("i686-pc-windows-msvc-elf").getObjectFormat());
   EXPECT_EQ(Triple::ELF, Triple("i686-pc-cygwin-elf").getObjectFormat());
 
+  EXPECT_EQ(Triple::ELF, Triple("systemz-ibm-linux").getObjectFormat());
+  EXPECT_EQ(Triple::ELF, Triple("systemz-ibm-unknown").getObjectFormat());
+
+  EXPECT_EQ(Triple::GOFF, Triple("s390x-ibm-zos").getObjectFormat());
+  EXPECT_EQ(Triple::GOFF, Triple("systemz-ibm-zos").getObjectFormat());
+  EXPECT_EQ(Triple::GOFF, Triple("s390x-ibm-zos-goff").getObjectFormat());
+  EXPECT_EQ(Triple::GOFF, Triple("s390x-unknown-zos-goff").getObjectFormat());
+  EXPECT_EQ(Triple::GOFF, Triple("s390x---goff").getObjectFormat());
+
   EXPECT_EQ(Triple::Wasm, Triple("wasm32-unknown-unknown").getObjectFormat());
   EXPECT_EQ(Triple::Wasm, Triple("wasm64-unknown-unknown").getObjectFormat());
   EXPECT_EQ(Triple::Wasm, Triple("wasm32-wasi").getObjectFormat());
@@ -1360,6 +1381,9 @@ TEST(TripleTest, FileFormat) {
 
   T.setObjectFormat(Triple::XCOFF);
   EXPECT_EQ(Triple::XCOFF, T.getObjectFormat());
+
+  T.setObjectFormat(Triple::GOFF);
+  EXPECT_EQ(Triple::GOFF, T.getObjectFormat());
 }
 
 TEST(TripleTest, NormalizeWindows) {