Refactor PPC target to separate MC routines from Target routines.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135942 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 123 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp b/lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp
new file mode 100644
index 0000000000..89881200d1
--- /dev/null
+++ b/lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp
@@ -0,0 +1,123 @@
+//===-- PPCAsmBackend.cpp - PPC Assembler Backend -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/TargetAsmBackend.h"
+#include "MCTargetDesc/PPCMCTargetDesc.h"
+#include "MCTargetDesc/PPCFixupKinds.h"
+#include "llvm/MC/MCMachObjectWriter.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Object/MachOFormat.h"
+#include "llvm/Target/TargetRegistry.h"
+using namespace llvm;
+
+namespace {
+class PPCMachObjectWriter : public MCMachObjectTargetWriter {
+public:
+  PPCMachObjectWriter(bool Is64Bit, uint32_t CPUType,
+                      uint32_t CPUSubtype)
+    : MCMachObjectTargetWriter(Is64Bit, CPUType, CPUSubtype) {}
+
+  void RecordRelocation(MachObjectWriter *Writer,
+                        const MCAssembler &Asm, const MCAsmLayout &Layout,
+                        const MCFragment *Fragment, const MCFixup &Fixup,
+                        MCValue Target, uint64_t &FixedValue) {}
+};
+
+class PPCAsmBackend : public TargetAsmBackend {
+const Target &TheTarget;
+public:
+  PPCAsmBackend(const Target &T) : TargetAsmBackend(), TheTarget(T) {}
+
+  unsigned getNumFixupKinds() const { return PPC::NumTargetFixupKinds; }
+
+  const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const {
+    const static MCFixupKindInfo Infos[PPC::NumTargetFixupKinds] = {
+      // name                    offset  bits  flags
+      { "fixup_ppc_br24",        6,      24,   MCFixupKindInfo::FKF_IsPCRel },
+      { "fixup_ppc_brcond14",    16,     14,   MCFixupKindInfo::FKF_IsPCRel },
+      { "fixup_ppc_lo16",        16,     16,   0 },
+      { "fixup_ppc_ha16",        16,     16,   0 },
+      { "fixup_ppc_lo14",        16,     14,   0 }
+    };
+  
+    if (Kind < FirstTargetFixupKind)
+      return TargetAsmBackend::getFixupKindInfo(Kind);
+  
+    assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
+           "Invalid kind!");
+    return Infos[Kind - FirstTargetFixupKind];
+  }
+  
+  bool MayNeedRelaxation(const MCInst &Inst) const {
+    // FIXME.
+    return false;
+  }
+  
+  void RelaxInstruction(const MCInst &Inst, MCInst &Res) const {
+    // FIXME.
+    assert(0 && "RelaxInstruction() unimplemented");
+  }
+  
+  bool WriteNopData(uint64_t Count, MCObjectWriter *OW) const {
+    // FIXME: Zero fill for now. That's not right, but at least will get the
+    // section size right.
+    for (uint64_t i = 0; i != Count; ++i)
+      OW->Write8(0);
+    return true;
+  }      
+  
+  unsigned getPointerSize() const {
+    StringRef Name = TheTarget.getName();
+    if (Name == "ppc64") return 8;
+    assert(Name == "ppc32" && "Unknown target name!");
+    return 4;
+  }
+};
+} // end anonymous namespace
+
+
+// FIXME: This should be in a separate file.
+namespace {
+  class DarwinPPCAsmBackend : public PPCAsmBackend {
+  public:
+    DarwinPPCAsmBackend(const Target &T) : PPCAsmBackend(T) { }
+    
+    void ApplyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
+                    uint64_t Value) const {
+      assert(0 && "UNIMP");
+    }
+    
+    MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
+      bool is64 = getPointerSize() == 8;
+      return createMachObjectWriter(new PPCMachObjectWriter(
+                                      /*Is64Bit=*/is64,
+                                      (is64 ? object::mach::CTM_PowerPC64 :
+                                       object::mach::CTM_PowerPC),
+                                      object::mach::CSPPC_ALL),
+                                    OS, /*IsLittleEndian=*/false);
+    }
+    
+    virtual bool doesSectionRequireSymbols(const MCSection &Section) const {
+      return false;
+    }
+  };
+} // end anonymous namespace
+
+
+
+
+TargetAsmBackend *llvm::createPPCAsmBackend(const Target &T,
+                                            const std::string &TT) {
+  if (Triple(TT).isOSDarwin())
+    return new DarwinPPCAsmBackend(T);
+
+  return 0;
+}