[llvm] [RISCV] Add basic Mach-O triple support. (PR #141682)

[Francesco Petrogalli via llvm-commits]

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@@ -0,0 +1,54 @@
+//===-- RISCVMachObjectWriter.cpp - RISC-V Mach Object 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/RISCVFixupKinds.h"
+#include "MCTargetDesc/RISCVMCTargetDesc.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/BinaryFormat/MachO.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCFixup.h"
+#include "llvm/MC/MCMachObjectWriter.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/MathExtras.h"
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+
+namespace {
+
+class RISCVMachObjectWriter : public MCMachObjectTargetWriter {
+public:
+  RISCVMachObjectWriter(uint32_t CPUType, uint32_t CPUSubtype)
+      : MCMachObjectTargetWriter(false, CPUType, CPUSubtype) {}
+
+  void recordRelocation(MachObjectWriter *Writer, MCAssembler &Asm,
+                        const MCFragment *Fragment, const MCFixup &Fixup,
+                        MCValue Target, uint64_t &FixedValue) override;
+};
+
+} // end anonymous namespace
+
+void RISCVMachObjectWriter::recordRelocation(
+    MachObjectWriter *Writer, MCAssembler &Asm, const MCFragment *Fragment,
+    const MCFixup &Fixup, MCValue Target, uint64_t &FixedValue) {
+  llvm_unreachable("unimplemented");
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fpetrogalli wrote:

Thanks for all the reviews. I am holding the merge of this PR, because I want to create a PR on top of this that implements the relocations.

https://github.com/llvm/llvm-project/pull/141682