1 files changed, 94 insertions, 0 deletions
diff --git a/lib/MC/XCOFFObjectWriter.cpp b/lib/MC/XCOFFObjectWriter.cpp
new file mode 100644
index 000000000000..9b9a7b6c118c
--- /dev/null
+++ b/lib/MC/XCOFFObjectWriter.cpp
@@ -0,0 +1,94 @@
+//===-- lib/MC/XCOFFObjectWriter.cpp - XCOFF file writer ------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements XCOFF object file writer information.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/MC/MCXCOFFObjectWriter.h"
+
+using namespace llvm;
+
+namespace {
+
+class XCOFFObjectWriter : public MCObjectWriter {
+  support::endian::Writer W;
+  std::unique_ptr<MCXCOFFObjectTargetWriter> TargetObjectWriter;
+
+  void executePostLayoutBinding(MCAssembler &, const MCAsmLayout &) override;
+
+  void recordRelocation(MCAssembler &, const MCAsmLayout &, const MCFragment *,
+                        const MCFixup &, MCValue, uint64_t &) override;
+
+  uint64_t writeObject(MCAssembler &, const MCAsmLayout &) override;
+
+public:
+  XCOFFObjectWriter(std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW,
+                    raw_pwrite_stream &OS);
+};
+
+XCOFFObjectWriter::XCOFFObjectWriter(
+    std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW, raw_pwrite_stream &OS)
+    : W(OS, support::big), TargetObjectWriter(std::move(MOTW)) {}
+
+void XCOFFObjectWriter::executePostLayoutBinding(MCAssembler &,
+                                                 const MCAsmLayout &) {
+  // TODO Implement once we have sections and symbols to handle.
+}
+
+void XCOFFObjectWriter::recordRelocation(MCAssembler &, const MCAsmLayout &,
+                                         const MCFragment *, const MCFixup &,
+                                         MCValue, uint64_t &) {
+  report_fatal_error("XCOFF relocations not supported.");
+}
+
+uint64_t XCOFFObjectWriter::writeObject(MCAssembler &Asm, const MCAsmLayout &) {
+  // We always emit a timestamp of 0 for reproducibility, so ensure incremental
+  // linking is not enabled, in case, like with Windows COFF, such a timestamp
+  // is incompatible with incremental linking of XCOFF.
+  if (Asm.isIncrementalLinkerCompatible())
+    report_fatal_error("Incremental linking not supported for XCOFF.");
+
+  if (TargetObjectWriter->is64Bit())
+    report_fatal_error("64-bit XCOFF object files are not supported yet.");
+
+  uint64_t StartOffset = W.OS.tell();
+
+  // TODO FIXME Assign section numbers/finalize sections.
+
+  // TODO FIXME Finalize symbols.
+
+  // Magic.
+  W.write<uint16_t>(0x01df);
+  // Number of sections.
+  W.write<uint16_t>(0);
+  // Timestamp field. For reproducible output we write a 0, which represents no
+  // timestamp.
+  W.write<int32_t>(0);
+  // Byte Offset to the start of the symbol table.
+  W.write<uint32_t>(0);
+  // Number of entries in the symbol table.
+  W.write<int32_t>(0);
+  // Size of the optional header.
+  W.write<uint16_t>(0);
+  // Flags.
+  W.write<uint16_t>(0);
+
+  return W.OS.tell() - StartOffset;
+}
+
+} // end anonymous namespace
+
+std::unique_ptr<MCObjectWriter>
+llvm::createXCOFFObjectWriter(std::unique_ptr<MCXCOFFObjectTargetWriter> MOTW,
+                              raw_pwrite_stream &OS) {
+  return llvm::make_unique<XCOFFObjectWriter>(std::move(MOTW), OS);
+}