[clang] [UEFI] X86_64 UEFI Clang Driver (PR #76838)

[via cfe-commits]

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@@ -0,0 +1,92 @@
+//===--- UEFI.h - UEFI 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 "UEFI.h"
+#include "CommonArgs.h"
+#include "Darwin.h"
+#include "clang/Basic/CharInfo.h"
+#include "clang/Basic/Version.h"
+#include "clang/Config/config.h"
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/Options.h"
+#include "clang/Driver/SanitizerArgs.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Option/Arg.h"
+#include "llvm/Option/ArgList.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/VirtualFileSystem.h"
+#include "llvm/TargetParser/Host.h"
+
+using namespace clang::driver;
+using namespace clang::driver::toolchains;
+using namespace clang;
+using namespace llvm::opt;
+
+UEFI::UEFI(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);
+}
+
+Tool *UEFI::buildLinker() const { return new tools::uefi::Linker(*this); }
+
+void tools::uefi::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::UEFI &>(getToolChain());
+
+  assert((Output.isFilename() || Output.isNothing()) && "invalid output");
+  if (Output.isFilename())
+    CmdArgs.push_back(
+        Args.MakeArgString(std::string("-out:") + Output.getFilename()));
+
+  CmdArgs.push_back("-nologo");
+
+  // TODO: Other UEFI binary subsystems that are currently unsupported:
+  // efi_boot_service_driver, efi_rom, efi_runtime_driver.
+  CmdArgs.push_back("-subsystem:efi_application");
+
+  // Default entry function name according to the TianoCore reference
+  // implementation is EfiMain.
+  // TODO: Provide a flag to override the entry function name.
+  CmdArgs.push_back("-entry:EfiMain");
+
+  // "Terminal Service Aware" flag is not needed for UEFI applications.
+  CmdArgs.push_back("-tsaware:no");
+
+  // EFI_APPLICATION to be linked as DLL by default.
+  CmdArgs.push_back("-dll");
+
+  if (Args.hasArg(options::OPT_g_Group, options::OPT__SLASH_Z7))
+    CmdArgs.push_back("-debug");
+
+  Args.AddAllArgValues(CmdArgs, options::OPT__SLASH_link);
+
+  AddLinkerInputs(TC, Inputs, Args, CmdArgs, JA);
+
+  // This should ideally be handled by ToolChain::GetLinkerPath but we need
+  // to special case some linker paths. In the case of lld, we need to
+  // translate 'lld' into 'lld-link'.
+  StringRef Linker =
+      Args.getLastArgValue(options::OPT_fuse_ld_EQ, CLANG_DEFAULT_LINKER);
+  if (Linker.empty() || Linker.equals("lld"))
+    Linker = "lld-link";
+
+  auto LinkerPath = TC.GetProgramPath(Linker.str().c_str());
+  auto LinkCmd = std::make_unique<Command>(
+      JA, *this, ResponseFileSupport::AtFileUTF16(),
----------------
Prabhuk wrote:

Yes. This maintains compatibility with LINK.exe which only supports UTF-16. 

https://github.com/llvm/llvm-project/pull/76838