[clang] Add managarm support (#139271)

This PR is part of a series to upstream managarm support, as laid out in
the
[RFC](https://discourse.llvm.org/t/rfc-new-proposed-managarm-support-for-llvm-and-clang-87845/85884/1).
This PR is a follow-up to #87845 and #138854.

Author: no92

clang/lib/Basic/Targets.cpp

@@ -164,6 +164,9 @@ std::unique_ptr<TargetInfo> AllocateTarget(const llvm::Triple &Triple,
         return std::make_unique<OHOSTargetInfo<AArch64leTargetInfo>>(Triple,
                                                                      Opts);
       }
+    case llvm::Triple::Managarm:
+      return std::make_unique<ManagarmTargetInfo<AArch64leTargetInfo>>(Triple,
+                                                                       Opts);
     case llvm::Triple::NetBSD:
       return std::make_unique<NetBSDTargetInfo<AArch64leTargetInfo>>(Triple,
                                                                      Opts);
@@ -466,6 +469,9 @@ std::unique_ptr<TargetInfo> AllocateTarget(const llvm::Triple &Triple,
         return std::make_unique<OHOSTargetInfo<RISCV64TargetInfo>>(Triple,
                                                                    Opts);
       }
+    case llvm::Triple::Managarm:
+      return std::make_unique<ManagarmTargetInfo<RISCV64TargetInfo>>(Triple,
+                                                                     Opts);
     default:
       return std::make_unique<RISCV64TargetInfo>(Triple, Opts);
     }
@@ -654,6 +660,9 @@ std::unique_ptr<TargetInfo> AllocateTarget(const llvm::Triple &Triple,
       return std::make_unique<PS5OSTargetInfo<X86_64TargetInfo>>(Triple, Opts);
     case llvm::Triple::Hurd:
       return std::make_unique<HurdTargetInfo<X86_64TargetInfo>>(Triple, Opts);
+    case llvm::Triple::Managarm:
+      return std::make_unique<ManagarmTargetInfo<X86_64TargetInfo>>(Triple,
+                                                                    Opts);
     default:
       return std::make_unique<X86_64TargetInfo>(Triple, Opts);
     }

clang/lib/Basic/Targets/OSTargets.h

@@ -395,6 +395,36 @@ class LLVM_LIBRARY_VISIBILITY LinuxTargetInfo : public OSTargetInfo<Target> {
   }
 };
 
+// Managarm Target
+template <typename Target>
+class LLVM_LIBRARY_VISIBILITY ManagarmTargetInfo : public OSTargetInfo<Target> {
+protected:
+  void getOSDefines(const LangOptions &Opts, const llvm::Triple &Triple,
+                    MacroBuilder &Builder) const override {
+    DefineStd(Builder, "unix", Opts);
+    Builder.defineMacro("__managarm__");
+    if (Opts.POSIXThreads)
+      Builder.defineMacro("_REENTRANT");
+    if (Opts.CPlusPlus)
+      Builder.defineMacro("_GNU_SOURCE");
+    if (this->HasFloat128)
+      Builder.defineMacro("__FLOAT128__");
+  }
+
+public:
+  ManagarmTargetInfo(const llvm::Triple &Triple, const TargetOptions &Opts)
+      : OSTargetInfo<Target>(Triple, Opts) {
+    switch (Triple.getArch()) {
+    default:
+      break;
+    case llvm::Triple::x86:
+    case llvm::Triple::x86_64:
+      this->HasFloat128 = true;
+      break;
+    }
+  }
+};
+
 // NetBSD Target
 template <typename Target>
 class LLVM_LIBRARY_VISIBILITY NetBSDTargetInfo : public OSTargetInfo<Target> {

clang/lib/Driver/CMakeLists.txt

@@ -66,6 +66,7 @@ add_clang_library(clangDriver
   ToolChains/HLSL.cpp
   ToolChains/Hurd.cpp
   ToolChains/Linux.cpp
+  ToolChains/Managarm.cpp
   ToolChains/MipsLinux.cpp
   ToolChains/MinGW.cpp
   ToolChains/MSP430.cpp

clang/lib/Driver/Driver.cpp

@@ -33,6 +33,7 @@
 #include "ToolChains/Linux.h"
 #include "ToolChains/MSP430.h"
 #include "ToolChains/MSVC.h"
+#include "ToolChains/Managarm.h"
 #include "ToolChains/MinGW.h"
 #include "ToolChains/MipsLinux.h"
 #include "ToolChains/NaCl.h"
@@ -6842,6 +6843,9 @@ const ToolChain &Driver::getToolChain(const ArgList &Args,
     case llvm::Triple::Fuchsia:
       TC = std::make_unique<toolchains::Fuchsia>(*this, Target, Args);
       break;
+    case llvm::Triple::Managarm:
+      TC = std::make_unique<toolchains::Managarm>(*this, Target, Args);
+      break;
     case llvm::Triple::Solaris:
       TC = std::make_unique<toolchains::Solaris>(*this, Target, Args);
       break;

clang/lib/Driver/ToolChains/Gnu.cpp

@@ -226,6 +226,8 @@ static const char *getLDMOption(const llvm::Triple &T, const ArgList &Args) {
       return "elf_iamcu";
     return "elf_i386";
   case llvm::Triple::aarch64:
+    if (T.isOSManagarm())
+      return "aarch64managarm";
     return "aarch64linux";
   case llvm::Triple::aarch64_be:
     return "aarch64linuxb";

clang/lib/Driver/ToolChains/Managarm.cpp

@@ -0,0 +1,218 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "Managarm.h"
+#include "Arch/ARM.h"
+#include "Arch/RISCV.h"
+#include "clang/Config/config.h"
+#include "clang/Driver/CommonArgs.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/Options.h"
+#include "clang/Driver/SanitizerArgs.h"
+#include "llvm/Option/ArgList.h"
+#include "llvm/Support/Path.h"
+
+using namespace clang::driver;
+using namespace clang::driver::toolchains;
+using namespace clang;
+using namespace llvm::opt;
+
+using tools::addPathIfExists;
+
+std::string Managarm::getMultiarchTriple(const Driver &D,
+                                         const llvm::Triple &TargetTriple,
+                                         StringRef SysRoot) const {
+  switch (TargetTriple.getArch()) {
+  default:
+    return TargetTriple.str();
+  case llvm::Triple::x86_64:
+    return "x86_64-managarm-" + TargetTriple.getEnvironmentName().str();
+  case llvm::Triple::aarch64:
+    return "aarch64-managarm-" + TargetTriple.getEnvironmentName().str();
+  case llvm::Triple::riscv64:
+    return "riscv64-managarm-" + TargetTriple.getEnvironmentName().str();
+  }
+}
+
+static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
+  // It happens that only x86, PPC and SPARC use the 'lib32' variant of
+  // oslibdir, and using that variant while targeting other architectures causes
+  // problems because the libraries are laid out in shared system roots that
+  // can't cope with a 'lib32' library search path being considered. So we only
+  // enable them when we know we may need it.
+  //
+  // FIXME: This is a bit of a hack. We should really unify this code for
+  // reasoning about oslibdir spellings with the lib dir spellings in the
+  // GCCInstallationDetector, but that is a more significant refactoring.
+  if (Triple.getArch() == llvm::Triple::x86 || Triple.isPPC32() ||
+      Triple.getArch() == llvm::Triple::sparc)
+    return "lib32";
+
+  if (Triple.getArch() == llvm::Triple::x86_64 && Triple.isX32())
+    return "libx32";
+
+  if (Triple.getArch() == llvm::Triple::riscv32)
+    return "lib32";
+
+  return Triple.isArch32Bit() ? "lib" : "lib64";
+}
+
+Managarm::Managarm(const Driver &D, const llvm::Triple &Triple,
+                   const ArgList &Args)
+    : Generic_ELF(D, Triple, Args) {
+  GCCInstallation.init(Triple, Args);
+  Multilibs = GCCInstallation.getMultilibs();
+  SelectedMultilibs.assign({GCCInstallation.getMultilib()});
+  std::string SysRoot = computeSysRoot();
+
+  ToolChain::path_list &PPaths = getProgramPaths();
+
+  Generic_GCC::PushPPaths(PPaths);
+
+#ifdef ENABLE_LINKER_BUILD_ID
+  ExtraOpts.push_back("--build-id");
+#endif
+
+  // The selection of paths to try here is designed to match the patterns which
+  // the GCC driver itself uses, as this is part of the GCC-compatible driver.
+  // This was determined by running GCC in a fake filesystem, creating all
+  // possible permutations of these directories, and seeing which ones it added
+  // to the link paths.
+  path_list &Paths = getFilePaths();
+
+  const std::string OSLibDir = std::string(getOSLibDir(Triple, Args));
+  const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
+
+  Generic_GCC::AddMultilibPaths(D, SysRoot, OSLibDir, MultiarchTriple, Paths);
+
+  addPathIfExists(D, concat(SysRoot, "/lib", MultiarchTriple), Paths);
+  addPathIfExists(D, concat(SysRoot, "/lib/..", OSLibDir), Paths);
+  addPathIfExists(D, concat(SysRoot, "/usr/lib", MultiarchTriple), Paths);
+  addPathIfExists(D, concat(SysRoot, "/usr", OSLibDir), Paths);
+
+  Generic_GCC::AddMultiarchPaths(D, SysRoot, OSLibDir, Paths);
+
+  addPathIfExists(D, concat(SysRoot, "/lib"), Paths);
+  addPathIfExists(D, concat(SysRoot, "/usr/lib"), Paths);
+}
+
+bool Managarm::HasNativeLLVMSupport() const { return true; }
+
+Tool *Managarm::buildLinker() const {
+  return new tools::gnutools::Linker(*this);
+}
+
+Tool *Managarm::buildAssembler() const {
+  return new tools::gnutools::Assembler(*this);
+}
+
+std::string Managarm::computeSysRoot() const {
+  if (!getDriver().SysRoot.empty())
+    return getDriver().SysRoot;
+  return std::string();
+}
+
+std::string Managarm::getDynamicLinker(const ArgList &Args) const {
+  switch (getTriple().getArch()) {
+  case llvm::Triple::aarch64:
+    return "/lib/aarch64-managarm/ld.so";
+  case llvm::Triple::riscv64: {
+    StringRef ABIName = tools::riscv::getRISCVABI(Args, getTriple());
+    return ("/lib/riscv64-managarm/ld-riscv64-" + ABIName + ".so").str();
+  }
+  case llvm::Triple::x86_64:
+    return "/lib/x86_64-managarm/ld.so";
+  default:
+    llvm_unreachable("unsupported architecture");
+  }
+}
+
+void Managarm::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
+                                         ArgStringList &CC1Args) const {
+  const Driver &D = getDriver();
+  std::string SysRoot = computeSysRoot();
+
+  if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
+    return;
+
+  if (!DriverArgs.hasArg(options::OPT_nostdlibinc))
+    addSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/local/include");
+
+  // Add 'include' in the resource directory, which is similar to
+  // GCC_INCLUDE_DIR (private headers) in GCC.
+  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
+    SmallString<128> ResourceDirInclude(D.ResourceDir);
+    llvm::sys::path::append(ResourceDirInclude, "include");
+    addSystemInclude(DriverArgs, CC1Args, ResourceDirInclude);
+  }
+
+  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
+    return;
+
+  // TOOL_INCLUDE_DIR
+  AddMultilibIncludeArgs(DriverArgs, CC1Args);
+
+  // Check for configure-time C include directories.
+  StringRef CIncludeDirs(C_INCLUDE_DIRS);
+  if (CIncludeDirs != "") {
+    SmallVector<StringRef, 5> dirs;
+    CIncludeDirs.split(dirs, ":");
+    for (StringRef dir : dirs) {
+      StringRef Prefix =
+          llvm::sys::path::is_absolute(dir) ? StringRef(SysRoot) : "";
+      addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
+    }
+    return;
+  }
+
+  // On systems using multiarch, add /usr/include/$triple before
+  // /usr/include.
+  std::string MultiarchIncludeDir = getMultiarchTriple(D, getTriple(), SysRoot);
+  if (!MultiarchIncludeDir.empty())
+    addExternCSystemInclude(
+        DriverArgs, CC1Args,
+        concat(SysRoot, "/usr/include", MultiarchIncludeDir));
+
+  // Add an include of '/include' directly. This isn't provided by default by
+  // system GCCs, but is often used with cross-compiling GCCs, and harmless to
+  // add even when Clang is acting as-if it were a system compiler.
+  addExternCSystemInclude(DriverArgs, CC1Args, concat(SysRoot, "/include"));
+
+  addExternCSystemInclude(DriverArgs, CC1Args, concat(SysRoot, "/usr/include"));
+}
+
+void Managarm::addLibStdCxxIncludePaths(
+    const llvm::opt::ArgList &DriverArgs,
+    llvm::opt::ArgStringList &CC1Args) const {
+  // We need a detected GCC installation on Managarm to provide libstdc++'s
+  // headers.
+  if (!GCCInstallation.isValid())
+    return;
+
+  StringRef TripleStr = GCCInstallation.getTriple().str();
+
+  // Try generic GCC detection.
+  Generic_GCC::addGCCLibStdCxxIncludePaths(DriverArgs, CC1Args, TripleStr);
+}
+
+SanitizerMask Managarm::getSupportedSanitizers() const {
+  const bool IsX86_64 = getTriple().getArch() == llvm::Triple::x86_64;
+  SanitizerMask Res = ToolChain::getSupportedSanitizers();
+  Res |= SanitizerKind::PointerCompare;
+  Res |= SanitizerKind::PointerSubtract;
+  Res |= SanitizerKind::KernelAddress;
+  Res |= SanitizerKind::Vptr;
+  if (IsX86_64)
+    Res |= SanitizerKind::KernelMemory;
+  return Res;
+}
+
+void Managarm::addExtraOpts(llvm::opt::ArgStringList &CmdArgs) const {
+  for (const auto &Opt : ExtraOpts)
+    CmdArgs.push_back(Opt.c_str());
+}

clang/lib/Driver/ToolChains/Managarm.h

@@ -0,0 +1,55 @@
+//===--- Managarm.h - Managarm ToolChain Implementations --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MANAGARM_H
+#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MANAGARM_H
+
+#include "Gnu.h"
+#include "clang/Driver/ToolChain.h"
+
+namespace clang {
+namespace driver {
+namespace toolchains {
+
+class LLVM_LIBRARY_VISIBILITY Managarm : public Generic_ELF {
+public:
+  Managarm(const Driver &D, const llvm::Triple &Triple,
+           const llvm::opt::ArgList &Args);
+
+  bool HasNativeLLVMSupport() const override;
+
+  std::string getMultiarchTriple(const Driver &D,
+                                 const llvm::Triple &TargetTriple,
+                                 StringRef SysRoot) const override;
+
+  void
+  AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                            llvm::opt::ArgStringList &CC1Args) const override;
+  void
+  addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
+                           llvm::opt::ArgStringList &CC1Args) const override;
+  SanitizerMask getSupportedSanitizers() const override;
+  std::string computeSysRoot() const override;
+
+  std::string getDynamicLinker(const llvm::opt::ArgList &Args) const override;
+
+  void addExtraOpts(llvm::opt::ArgStringList &CmdArgs) const override;
+
+  std::vector<std::string> ExtraOpts;
+
+protected:
+  Tool *buildAssembler() const override;
+  Tool *buildLinker() const override;
+};
+
+} // end namespace toolchains
+} // end namespace driver
+} // end namespace clang
+
+#endif // LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_MANAGARM_H

clang/lib/Lex/InitHeaderSearch.cpp

@@ -221,6 +221,7 @@ bool InitHeaderSearch::ShouldAddDefaultIncludePaths(
   case llvm::Triple::Hurd:
   case llvm::Triple::Linux:
   case llvm::Triple::LiteOS:
+  case llvm::Triple::Managarm:
   case llvm::Triple::NaCl:
   case llvm::Triple::NetBSD:
   case llvm::Triple::OpenBSD: