1 files changed, 289 insertions, 0 deletions
diff --git a/clang/lib/Driver/ToolChains/WebAssembly.cpp b/clang/lib/Driver/ToolChains/WebAssembly.cpp
new file mode 100644
index 000000000000..3add913b700f
--- /dev/null
+++ b/clang/lib/Driver/ToolChains/WebAssembly.cpp
@@ -0,0 +1,289 @@
+//===--- WebAssembly.cpp - WebAssembly ToolChain Implementation -*- 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 "WebAssembly.h"
+#include "CommonArgs.h"
+#include "clang/Config/config.h"
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/DriverDiagnostic.h"
+#include "clang/Driver/Options.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Option/ArgList.h"
+
+using namespace clang::driver;
+using namespace clang::driver::tools;
+using namespace clang::driver::toolchains;
+using namespace clang;
+using namespace llvm::opt;
+
+/// Following the conventions in https://wiki.debian.org/Multiarch/Tuples,
+/// we remove the vendor field to form the multiarch triple.
+static std::string getMultiarchTriple(const Driver &D,
+                                      const llvm::Triple &TargetTriple,
+                                      StringRef SysRoot) {
+    return (TargetTriple.getArchName() + "-" +
+            TargetTriple.getOSAndEnvironmentName()).str();
+}
+
+std::string wasm::Linker::getLinkerPath(const ArgList &Args) const {
+  const ToolChain &ToolChain = getToolChain();
+  if (const Arg* A = Args.getLastArg(options::OPT_fuse_ld_EQ)) {
+    StringRef UseLinker = A->getValue();
+    if (!UseLinker.empty()) {
+      if (llvm::sys::path::is_absolute(UseLinker) &&
+          llvm::sys::fs::can_execute(UseLinker))
+        return UseLinker;
+
+      // Accept 'lld', and 'ld' as aliases for the default linker
+      if (UseLinker != "lld" && UseLinker != "ld")
+        ToolChain.getDriver().Diag(diag::err_drv_invalid_linker_name)
+            << A->getAsString(Args);
+    }
+  }
+
+  return ToolChain.GetProgramPath(ToolChain.getDefaultLinker());
+}
+
+void wasm::Linker::ConstructJob(Compilation &C, const JobAction &JA,
+                                const InputInfo &Output,
+                                const InputInfoList &Inputs,
+                                const ArgList &Args,
+                                const char *LinkingOutput) const {
+
+  const ToolChain &ToolChain = getToolChain();
+  const char *Linker = Args.MakeArgString(getLinkerPath(Args));
+  ArgStringList CmdArgs;
+
+  if (Args.hasArg(options::OPT_s))
+    CmdArgs.push_back("--strip-all");
+
+  Args.AddAllArgs(CmdArgs, options::OPT_L);
+  Args.AddAllArgs(CmdArgs, options::OPT_u);
+  ToolChain.AddFilePathLibArgs(Args, CmdArgs);
+
+  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles))
+    CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt1.o")));
+
+  AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA);
+
+  if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
+    if (ToolChain.ShouldLinkCXXStdlib(Args))
+      ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs);
+
+    if (Args.hasArg(options::OPT_pthread)) {
+      CmdArgs.push_back("-lpthread");
+      CmdArgs.push_back("--shared-memory");
+    }
+
+    CmdArgs.push_back("-lc");
+    AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args);
+  }
+
+  CmdArgs.push_back("-o");
+  CmdArgs.push_back(Output.getFilename());
+
+  C.addCommand(std::make_unique<Command>(JA, *this, Linker, CmdArgs, Inputs));
+}
+
+WebAssembly::WebAssembly(const Driver &D, const llvm::Triple &Triple,
+                         const llvm::opt::ArgList &Args)
+    : ToolChain(D, Triple, Args) {
+
+  assert(Triple.isArch32Bit() != Triple.isArch64Bit());
+
+  getProgramPaths().push_back(getDriver().getInstalledDir());
+
+  if (getTriple().getOS() == llvm::Triple::UnknownOS) {
+    // Theoretically an "unknown" OS should mean no standard libraries, however
+    // it could also mean that a custom set of libraries is in use, so just add
+    // /lib to the search path. Disable multiarch in this case, to discourage
+    // paths containing "unknown" from acquiring meanings.
+    getFilePaths().push_back(getDriver().SysRoot + "/lib");
+  } else {
+    const std::string MultiarchTriple =
+        getMultiarchTriple(getDriver(), Triple, getDriver().SysRoot);
+    getFilePaths().push_back(getDriver().SysRoot + "/lib/" + MultiarchTriple);
+  }
+}
+
+bool WebAssembly::IsMathErrnoDefault() const { return false; }
+
+bool WebAssembly::IsObjCNonFragileABIDefault() const { return true; }
+
+bool WebAssembly::UseObjCMixedDispatch() const { return true; }
+
+bool WebAssembly::isPICDefault() const { return false; }
+
+bool WebAssembly::isPIEDefault() const { return false; }
+
+bool WebAssembly::isPICDefaultForced() const { return false; }
+
+bool WebAssembly::IsIntegratedAssemblerDefault() const { return true; }
+
+bool WebAssembly::hasBlocksRuntime() const { return false; }
+
+// TODO: Support profiling.
+bool WebAssembly::SupportsProfiling() const { return false; }
+
+bool WebAssembly::HasNativeLLVMSupport() const { return true; }
+
+void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs,
+                                        ArgStringList &CC1Args,
+                                        Action::OffloadKind) const {
+  if (DriverArgs.hasFlag(clang::driver::options::OPT_fuse_init_array,
+                         options::OPT_fno_use_init_array, true))
+    CC1Args.push_back("-fuse-init-array");
+
+  // '-pthread' implies atomics, bulk-memory, mutable-globals, and sign-ext
+  if (DriverArgs.hasFlag(options::OPT_pthread, options::OPT_no_pthread,
+                         false)) {
+    if (DriverArgs.hasFlag(options::OPT_mno_atomics, options::OPT_matomics,
+                           false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-atomics";
+    if (DriverArgs.hasFlag(options::OPT_mno_bulk_memory,
+                           options::OPT_mbulk_memory, false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-bulk-memory";
+    if (DriverArgs.hasFlag(options::OPT_mno_mutable_globals,
+                           options::OPT_mmutable_globals, false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-mutable-globals";
+    if (DriverArgs.hasFlag(options::OPT_mno_sign_ext, options::OPT_msign_ext,
+                           false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-pthread"
+          << "-mno-sign-ext";
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+atomics");
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+bulk-memory");
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+mutable-globals");
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+sign-ext");
+  }
+
+  if (DriverArgs.getLastArg(options::OPT_fwasm_exceptions)) {
+    // '-fwasm-exceptions' is not compatible with '-mno-exception-handling'
+    if (DriverArgs.hasFlag(options::OPT_mno_exception_handing,
+                           options::OPT_mexception_handing, false))
+      getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+          << "-fwasm-exceptions"
+          << "-mno-exception-handling";
+    // '-fwasm-exceptions' is not compatible with
+    // '-mllvm -enable-emscripten-cxx-exceptions'
+    for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) {
+      if (StringRef(A->getValue(0)) == "-enable-emscripten-cxx-exceptions")
+        getDriver().Diag(diag::err_drv_argument_not_allowed_with)
+            << "-fwasm-exceptions"
+            << "-mllvm -enable-emscripten-cxx-exceptions";
+    }
+    // '-fwasm-exceptions' implies exception-handling
+    CC1Args.push_back("-target-feature");
+    CC1Args.push_back("+exception-handling");
+  }
+}
+
+ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const {
+  return ToolChain::RLT_CompilerRT;
+}
+
+ToolChain::CXXStdlibType
+WebAssembly::GetCXXStdlibType(const ArgList &Args) const {
+  if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
+    StringRef Value = A->getValue();
+    if (Value != "libc++")
+      getDriver().Diag(diag::err_drv_invalid_stdlib_name)
+          << A->getAsString(Args);
+  }
+  return ToolChain::CST_Libcxx;
+}
+
+void WebAssembly::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
+                                            ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
+    return;
+
+  const Driver &D = getDriver();
+
+  if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
+    SmallString<128> P(D.ResourceDir);
+    llvm::sys::path::append(P, "include");
+    addSystemInclude(DriverArgs, CC1Args, P);
+  }
+
+  if (DriverArgs.hasArg(options::OPT_nostdlibinc))
+    return;
+
+  // 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(D.SysRoot) : "";
+      addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
+    }
+    return;
+  }
+
+  if (getTriple().getOS() != llvm::Triple::UnknownOS) {
+    const std::string MultiarchTriple =
+        getMultiarchTriple(D, getTriple(), D.SysRoot);
+    addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include/" + MultiarchTriple);
+  }
+  addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include");
+}
+
+void WebAssembly::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
+                                               ArgStringList &CC1Args) const {
+  if (!DriverArgs.hasArg(options::OPT_nostdlibinc) &&
+      !DriverArgs.hasArg(options::OPT_nostdincxx)) {
+    if (getTriple().getOS() != llvm::Triple::UnknownOS) {
+      const std::string MultiarchTriple =
+          getMultiarchTriple(getDriver(), getTriple(), getDriver().SysRoot);
+      addSystemInclude(DriverArgs, CC1Args,
+                       getDriver().SysRoot + "/include/" + MultiarchTriple +
+                           "/c++/v1");
+    }
+    addSystemInclude(DriverArgs, CC1Args,
+                     getDriver().SysRoot + "/include/c++/v1");
+  }
+}
+
+void WebAssembly::AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
+                                      llvm::opt::ArgStringList &CmdArgs) const {
+
+  switch (GetCXXStdlibType(Args)) {
+  case ToolChain::CST_Libcxx:
+    CmdArgs.push_back("-lc++");
+    CmdArgs.push_back("-lc++abi");
+    break;
+  case ToolChain::CST_Libstdcxx:
+    llvm_unreachable("invalid stdlib name");
+  }
+}
+
+SanitizerMask WebAssembly::getSupportedSanitizers() const {
+  SanitizerMask Res = ToolChain::getSupportedSanitizers();
+  if (getTriple().isOSEmscripten()) {
+    Res |= SanitizerKind::Vptr | SanitizerKind::Leak | SanitizerKind::Address;
+  }
+  return Res;
+}
+
+Tool *WebAssembly::buildLinker() const {
+  return new tools::wasm::Linker(*this);
+}