[WebAssembly] Add skeleton MC support for the Wasm container format

This just adds the basic skeleton for supporting a new object file format.
All of the actual encoding will be implemented in followup patches.

Differential Revision: https://reviews.llvm.org/D26722


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295803 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/MCWasmObjectTargetWriter.cpp

@@ -0,0 +1,27 @@
+//===-- MCWasmObjectTargetWriter.cpp - Wasm Target Writer Subclass --------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/MC/MCWasmObjectWriter.h"
+
+using namespace llvm;
+
+MCWasmObjectTargetWriter::MCWasmObjectTargetWriter(bool Is64Bit_)
+    : Is64Bit(Is64Bit_) {}
+
+bool MCWasmObjectTargetWriter::needsRelocateWithSymbol(const MCSymbol &Sym,
+                                                       unsigned Type) const {
+  return false;
+}
+
+void MCWasmObjectTargetWriter::sortRelocs(
+    const MCAssembler &Asm, std::vector<WasmRelocationEntry> &Relocs) {
+}