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

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,61 @@
+//===--- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_UEFI_H
+#define LLVM_CLANG_LIB_DRIVER_TOOLCHAINS_UEFI_H
+
+#include "clang/Driver/Tool.h"
+#include "clang/Driver/ToolChain.h"
+
+namespace clang {
+namespace driver {
+namespace tools {
+namespace uefi {
+class LLVM_LIBRARY_VISIBILITY Linker : public Tool {
+public:
+  Linker(const ToolChain &TC) : Tool("uefi::Linker", "lld-link", TC) {}
+
+  bool hasIntegratedCPP() const override { return false; }
+  bool isLinkJob() const override { return true; }
+
+  void ConstructJob(Compilation &C, const JobAction &JA,
+                    const InputInfo &Output, const InputInfoList &Inputs,
+                    const llvm::opt::ArgList &TCArgs,
+                    const char *LinkingOutput) const override;
+};
+} // end namespace uefi
+} // end namespace tools
+
+namespace toolchains {
+
+class LLVM_LIBRARY_VISIBILITY UEFI : public ToolChain {
+public:
+  UEFI(const Driver &D, const llvm::Triple &Triple,
+       const llvm::opt::ArgList &Args);
+
+protected:
+  Tool *buildLinker() const override;
+
+public:
+  bool HasNativeLLVMSupport() const override { return true; }
+  UnwindTableLevel
+  getDefaultUnwindTableLevel(const llvm::opt::ArgList &Args) const override {
+    return UnwindTableLevel::Asynchronous;
+  }
+  bool isPICDefault() const override { return true; }
----------------
MaskRay wrote:

Q: why is this PIC and forced (`-fno-pic` will error)?

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