1 files changed, 197 insertions, 0 deletions
diff --git a/clang/lib/Driver/ToolChains/BareMetal.cpp b/clang/lib/Driver/ToolChains/BareMetal.cpp
new file mode 100644
index 000000000000..dff0e04183ef
--- /dev/null
+++ b/clang/lib/Driver/ToolChains/BareMetal.cpp
@@ -0,0 +1,197 @@
+//===-- BareMetal.cpp - Bare Metal ToolChain --------------------*- 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 "BareMetal.h"
+
+#include "CommonArgs.h"
+#include "InputInfo.h"
+#include "Gnu.h"
+
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/DriverDiagnostic.h"
+#include "clang/Driver/Options.h"
+#include "llvm/Option/ArgList.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/VirtualFileSystem.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm::opt;
+using namespace clang;
+using namespace clang::driver;
+using namespace clang::driver::tools;
+using namespace clang::driver::toolchains;
+
+BareMetal::BareMetal(const Driver &D, const llvm::Triple &Triple,
+                           const ArgList &Args)
+    : ToolChain(D, Triple, Args) {
+  getProgramPaths().push_back(getDriver().getInstalledDir());
+  if (getDriver().getInstalledDir() != getDriver().Dir)
+    getProgramPaths().push_back(getDriver().Dir);
+}
+
+BareMetal::~BareMetal() {}
+
+/// Is the triple {arm,thumb}-none-none-{eabi,eabihf} ?
+static bool isARMBareMetal(const llvm::Triple &Triple) {
+  if (Triple.getArch() != llvm::Triple::arm &&
+      Triple.getArch() != llvm::Triple::thumb)
+    return false;
+
+  if (Triple.getVendor() != llvm::Triple::UnknownVendor)
+    return false;
+
+  if (Triple.getOS() != llvm::Triple::UnknownOS)
+    return false;
+
+  if (Triple.getEnvironment() != llvm::Triple::EABI &&
+      Triple.getEnvironment() != llvm::Triple::EABIHF)
+    return false;
+
+  return true;
+}
+
+bool BareMetal::handlesTarget(const llvm::Triple &Triple) {
+  return isARMBareMetal(Triple);
+}
+
+Tool *BareMetal::buildLinker() const {
+  return new tools::baremetal::Linker(*this);
+}
+
+std::string BareMetal::getRuntimesDir() const {
+  SmallString<128> Dir(getDriver().ResourceDir);
+  llvm::sys::path::append(Dir, "lib", "baremetal");
+  return Dir.str();
+}
+
+void BareMetal::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
+                                          ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(options::OPT_nostdinc))
+    return;
+
+  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
+    SmallString<128> Dir(getDriver().ResourceDir);
+    llvm::sys::path::append(Dir, "include");
+    addSystemInclude(DriverArgs, CC1Args, Dir.str());
+  }
+
+  if (!DriverArgs.hasArg(options::OPT_nostdlibinc)) {
+    SmallString<128> Dir(getDriver().SysRoot);
+    llvm::sys::path::append(Dir, "include");
+    addSystemInclude(DriverArgs, CC1Args, Dir.str());
+  }
+}
+
+void BareMetal::addClangTargetOptions(const ArgList &DriverArgs,
+                                      ArgStringList &CC1Args,
+                                      Action::OffloadKind) const {
+  CC1Args.push_back("-nostdsysteminc");
+}
+
+void BareMetal::AddClangCXXStdlibIncludeArgs(
+    const ArgList &DriverArgs, ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(options::OPT_nostdinc) ||
+      DriverArgs.hasArg(options::OPT_nostdlibinc) ||
+      DriverArgs.hasArg(options::OPT_nostdincxx))
+    return;
+
+  StringRef SysRoot = getDriver().SysRoot;
+  if (SysRoot.empty())
+    return;
+
+  switch (GetCXXStdlibType(DriverArgs)) {
+  case ToolChain::CST_Libcxx: {
+    SmallString<128> Dir(SysRoot);
+    llvm::sys::path::append(Dir, "include", "c++", "v1");
+    addSystemInclude(DriverArgs, CC1Args, Dir.str());
+    break;
+  }
+  case ToolChain::CST_Libstdcxx: {
+    SmallString<128> Dir(SysRoot);
+    llvm::sys::path::append(Dir, "include", "c++");
+    std::error_code EC;
+    Generic_GCC::GCCVersion Version = {"", -1, -1, -1, "", "", ""};
+    // Walk the subdirs, and find the one with the newest gcc version:
+    for (llvm::vfs::directory_iterator
+             LI = getDriver().getVFS().dir_begin(Dir.str(), EC),
+             LE;
+         !EC && LI != LE; LI = LI.increment(EC)) {
+      StringRef VersionText = llvm::sys::path::filename(LI->path());
+      auto CandidateVersion = Generic_GCC::GCCVersion::Parse(VersionText);
+      if (CandidateVersion.Major == -1)
+        continue;
+      if (CandidateVersion <= Version)
+        continue;
+      Version = CandidateVersion;
+    }
+    if (Version.Major == -1)
+      return;
+    llvm::sys::path::append(Dir, Version.Text);
+    addSystemInclude(DriverArgs, CC1Args, Dir.str());
+    break;
+  }
+  }
+}
+
+void BareMetal::AddCXXStdlibLibArgs(const ArgList &Args,
+                                    ArgStringList &CmdArgs) const {
+  switch (GetCXXStdlibType(Args)) {
+  case ToolChain::CST_Libcxx:
+    CmdArgs.push_back("-lc++");
+    CmdArgs.push_back("-lc++abi");
+    break;
+  case ToolChain::CST_Libstdcxx:
+    CmdArgs.push_back("-lstdc++");
+    CmdArgs.push_back("-lsupc++");
+    break;
+  }
+  CmdArgs.push_back("-lunwind");
+}
+
+void BareMetal::AddLinkRuntimeLib(const ArgList &Args,
+                                  ArgStringList &CmdArgs) const {
+  CmdArgs.push_back(Args.MakeArgString("-lclang_rt.builtins-" +
+                                       getTriple().getArchName() + ".a"));
+}
+
+void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
+                                     const InputInfo &Output,
+                                     const InputInfoList &Inputs,
+                                     const ArgList &Args,
+                                     const char *LinkingOutput) const {
+  ArgStringList CmdArgs;
+
+  auto &TC = static_cast<const toolchains::BareMetal&>(getToolChain());
+
+  AddLinkerInputs(TC, Inputs, Args, CmdArgs, JA);
+
+  CmdArgs.push_back("-Bstatic");
+
+  CmdArgs.push_back(Args.MakeArgString("-L" + TC.getRuntimesDir()));
+
+  Args.AddAllArgs(CmdArgs, {options::OPT_L, options::OPT_T_Group,
+                            options::OPT_e, options::OPT_s, options::OPT_t,
+                            options::OPT_Z_Flag, options::OPT_r});
+
+  if (TC.ShouldLinkCXXStdlib(Args))
+    TC.AddCXXStdlibLibArgs(Args, CmdArgs);
+  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
+    CmdArgs.push_back("-lc");
+    CmdArgs.push_back("-lm");
+
+    TC.AddLinkRuntimeLib(Args, CmdArgs);
+  }
+
+  CmdArgs.push_back("-o");
+  CmdArgs.push_back(Output.getFilename());
+
+  C.addCommand(std::make_unique<Command>(JA, *this,
+                                          Args.MakeArgString(TC.GetLinkerPath()),
+                                          CmdArgs, Inputs));
+}