[SystemZ][z/OS] Adding initial toolchain for z/OS

This patch adds the initial toolchain for z/OS that will set some defaults. In subsequent patches, we plan to add support to use the system linker and assembler.

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D86707

clang/lib/Driver/CMakeLists.txt

@@ -73,6 +73,7 @@ add_clang_library(clangDriver
   ToolChains/XCore.cpp
   ToolChains/PPCLinux.cpp
   ToolChains/InterfaceStubs.cpp
+  ToolChains/ZOS.cpp
   Types.cpp
   XRayArgs.cpp
 

clang/lib/Driver/Driver.cpp

@@ -46,6 +46,7 @@
 #include "ToolChains/VEToolchain.h"
 #include "ToolChains/WebAssembly.h"
 #include "ToolChains/XCore.h"
+#include "ToolChains/ZOS.h"
 #include "clang/Basic/TargetID.h"
 #include "clang/Basic/Version.h"
 #include "clang/Config/config.h"
@@ -5072,6 +5073,9 @@ const ToolChain &Driver::getToolChain(const ArgList &Args,
     case llvm::Triple::Hurd:
       TC = std::make_unique<toolchains::Hurd>(*this, Target, Args);
       break;
+    case llvm::Triple::ZOS:
+      TC = std::make_unique<toolchains::ZOS>(*this, Target, Args);
+      break;
     default:
       // Of these targets, Hexagon is the only one that might have
       // an OS of Linux, in which case it got handled above already.

clang/lib/Driver/ToolChains/ZOS.cpp

@@ -0,0 +1,21 @@
+//===--- ZOS.cpp - z/OS ToolChain Implementations ---------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "ZOS.h"
+#include "CommonArgs.h"
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Options.h"
+#include "llvm/Option/ArgList.h"
+
+using namespace clang::driver::toolchains;
+using namespace llvm::opt;
+
+ZOS::ZOS(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
+    : ToolChain(D, Triple, Args) {}
+
+ZOS::~ZOS() {}

clang/lib/Driver/ToolChains/ZOS.h

@@ -0,0 +1,36 @@
+//===--- ZOS.h - z/OS ToolChain Implementations -----------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_ZOS_H
+#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_ZOS_H
+
+#include "clang/Driver/Tool.h"
+#include "clang/Driver/ToolChain.h"
+
+namespace clang {
+namespace driver {
+namespace toolchains {
+
+class LLVM_LIBRARY_VISIBILITY ZOS : public ToolChain {
+public:
+  ZOS(const Driver &D, const llvm::Triple &Triple,
+      const llvm::opt::ArgList &Args);
+  ~ZOS() override;
+
+  bool isPICDefault() const override { return false; }
+  bool isPIEDefault() const override { return false; }
+  bool isPICDefaultForced() const override { return false; }
+
+  bool IsIntegratedAssemblerDefault() const override { return true; }
+};
+
+} // end namespace toolchains
+} // end namespace driver
+} // end namespace clang
+
+#endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_ZOS_H