[Sparc] Add initial implementation of MC Code emitter for sparc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198533 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Sparc/MCTargetDesc/SparcMCCodeEmitter.cpp

@@ -0,0 +1,131 @@
+//===-- SparcMCCodeEmitter.cpp - Convert Sparc code to machine code -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the SparcMCCodeEmitter class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "mccodeemitter"
+#include "SparcMCTargetDesc.h"
+#include "MCTargetDesc/SparcFixupKinds.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
+
+namespace {
+class SparcMCCodeEmitter : public MCCodeEmitter {
+  SparcMCCodeEmitter(const SparcMCCodeEmitter &) LLVM_DELETED_FUNCTION;
+  void operator=(const SparcMCCodeEmitter &) LLVM_DELETED_FUNCTION;
+  MCContext &Ctx;
+
+public:
+  SparcMCCodeEmitter(MCContext &ctx): Ctx(ctx) {}
+
+  ~SparcMCCodeEmitter() {}
+
+  void EncodeInstruction(const MCInst &MI, raw_ostream &OS,
+                         SmallVectorImpl<MCFixup> &Fixups) const;
+
+  // getBinaryCodeForInstr - TableGen'erated function for getting the
+  // binary encoding for an instruction.
+  uint64_t getBinaryCodeForInstr(const MCInst &MI,
+                                 SmallVectorImpl<MCFixup> &Fixups) const;
+
+  /// getMachineOpValue - Return binary encoding of operand. If the machine
+  /// operand requires relocation, record the relocation and return zero.
+  unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+
+  unsigned getCallTargetOpValue(const MCInst &MI, unsigned OpNo,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+
+};
+} // end anonymous namespace
+
+MCCodeEmitter *llvm::createSparcMCCodeEmitter(const MCInstrInfo &MCII,
+                                              const MCRegisterInfo &MRI,
+                                              const MCSubtargetInfo &STI,
+                                              MCContext &Ctx) {
+  return new SparcMCCodeEmitter(Ctx);
+}
+
+void SparcMCCodeEmitter::
+EncodeInstruction(const MCInst &MI, raw_ostream &OS,
+                  SmallVectorImpl<MCFixup> &Fixups) const {
+  unsigned Bits = getBinaryCodeForInstr(MI, Fixups);
+
+  // Output the constant in big endian byte order.
+  for (unsigned i = 0; i != 4; ++i) {
+    OS << (char)(Bits >> 24);
+    Bits <<= 8;
+  }
+
+  ++MCNumEmitted;  // Keep track of the # of mi's emitted.
+}
+
+
+unsigned SparcMCCodeEmitter::
+getMachineOpValue(const MCInst &MI, const MCOperand &MO,
+                  SmallVectorImpl<MCFixup> &Fixups) const {
+
+  if (MO.isReg())
+    return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
+
+  if (MO.isImm())
+    return MO.getImm();
+
+  assert(MO.isExpr());
+  const MCExpr *Expr = MO.getExpr();
+  int64_t Res;
+  if (Expr->EvaluateAsAbsolute(Res))
+    return Res;
+
+  assert(0 && "Unhandled expression!");
+  return 0;
+}
+
+unsigned SparcMCCodeEmitter::
+getCallTargetOpValue(const MCInst &MI, unsigned OpNo,
+                     SmallVectorImpl<MCFixup> &Fixups) const {
+  const MCOperand &MO = MI.getOperand(OpNo);
+  if (MO.isReg() || MO.isImm())
+    return getMachineOpValue(MI, MO, Fixups);
+
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)Sparc::fixup_sparc_call30));
+  return 0;
+}
+
+unsigned SparcMCCodeEmitter::
+getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
+                  SmallVectorImpl<MCFixup> &Fixups) const {
+  const MCOperand &MO = MI.getOperand(OpNo);
+  if (MO.isReg() || MO.isImm())
+    return getMachineOpValue(MI, MO, Fixups);
+
+  Sparc::Fixups fixup = Sparc::fixup_sparc_br22;
+  if (MI.getOpcode() == SP::BPXCC)
+    fixup = Sparc::fixup_sparc_br19;
+
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)fixup));
+  return 0;
+}
+
+#include "SparcGenMCCodeEmitter.inc"