Update llvm to trunk r256633.

1 files changed, 103 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp b/contrib/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp
new file mode 100644
index 0000000..b158ccb
--- /dev/null
+++ b/contrib/llvm/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyAsmBackend.cpp
@@ -0,0 +1,103 @@
+//===-- WebAssemblyAsmBackend.cpp - WebAssembly Assembler Backend ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file implements the WebAssemblyAsmBackend class.
+///
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
+#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCELFObjectWriter.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCFixupKindInfo.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+namespace {
+class WebAssemblyAsmBackend final : public MCAsmBackend {
+  bool Is64Bit;
+
+public:
+  explicit WebAssemblyAsmBackend(bool Is64Bit)
+      : MCAsmBackend(), Is64Bit(Is64Bit) {}
+  ~WebAssemblyAsmBackend() override {}
+
+  void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
+                  uint64_t Value, bool IsPCRel) const override;
+
+  MCObjectWriter *createObjectWriter(raw_pwrite_stream &OS) const override;
+
+  // No instruction requires relaxation
+  bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
+                            const MCRelaxableFragment *DF,
+                            const MCAsmLayout &Layout) const override {
+    return false;
+  }
+
+  unsigned getNumFixupKinds() const override {
+    // We currently just use the generic fixups in MCFixup.h and don't have any
+    // target-specific fixups.
+    return 0;
+  }
+
+  bool mayNeedRelaxation(const MCInst &Inst) const override { return false; }
+
+  void relaxInstruction(const MCInst &Inst, MCInst &Res) const override {}
+
+  bool writeNopData(uint64_t Count, MCObjectWriter *OW) const override;
+};
+
+bool WebAssemblyAsmBackend::writeNopData(uint64_t Count,
+                                         MCObjectWriter *OW) const {
+  if (Count == 0)
+    return true;
+
+  // FIXME: Do something.
+  return false;
+}
+
+void WebAssemblyAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
+                                       unsigned DataSize, uint64_t Value,
+                                       bool IsPCRel) const {
+  const MCFixupKindInfo &Info = getFixupKindInfo(Fixup.getKind());
+  unsigned NumBytes = RoundUpToAlignment(Info.TargetSize, 8);
+  if (!Value)
+    return; // Doesn't change encoding.
+
+  // Shift the value into position.
+  Value <<= Info.TargetOffset;
+
+  unsigned Offset = Fixup.getOffset();
+  assert(Offset + NumBytes <= DataSize && "Invalid fixup offset!");
+
+  // For each byte of the fragment that the fixup touches, mask in the
+  // bits from the fixup value.
+  for (unsigned i = 0; i != NumBytes; ++i)
+    Data[Offset + i] |= uint8_t((Value >> (i * 8)) & 0xff);
+}
+
+MCObjectWriter *
+WebAssemblyAsmBackend::createObjectWriter(raw_pwrite_stream &OS) const {
+  return createWebAssemblyELFObjectWriter(OS, Is64Bit, 0);
+}
+} // end anonymous namespace
+
+MCAsmBackend *llvm::createWebAssemblyAsmBackend(const Target &T,
+                                                const MCRegisterInfo &MRI,
+                                                const Triple &TT,
+                                                StringRef CPU) {
+  return new WebAssemblyAsmBackend(TT.isArch64Bit());
+}