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, 193 insertions, 0 deletions

diff --git a/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp b/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
new file mode 100644
index 0000000..262f97c
--- /dev/null
+++ b/lib/Target/PowerPC/MCTargetDesc/PPCMCCodeEmitter.cpp
@@ -0,0 +1,193 @@
+//===-- PPCMCCodeEmitter.cpp - Convert PPC 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 PPCMCCodeEmitter class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "mccodeemitter"
+#include "MCTargetDesc/PPCBaseInfo.h"
+#include "MCTargetDesc/PPCFixupKinds.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+using namespace llvm;
+
+STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
+
+namespace {
+class PPCMCCodeEmitter : public MCCodeEmitter {
+  PPCMCCodeEmitter(const PPCMCCodeEmitter &); // DO NOT IMPLEMENT
+  void operator=(const PPCMCCodeEmitter &);   // DO NOT IMPLEMENT
+  
+public:
+  PPCMCCodeEmitter(const MCInstrInfo &mcii, const MCSubtargetInfo &sti,
+                   MCContext &ctx) {
+  }
+  
+  ~PPCMCCodeEmitter() {}
+
+  unsigned getDirectBrEncoding(const MCInst &MI, unsigned OpNo,
+                               SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getCondBrEncoding(const MCInst &MI, unsigned OpNo,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getHA16Encoding(const MCInst &MI, unsigned OpNo,
+                           SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getLO16Encoding(const MCInst &MI, unsigned OpNo,
+                           SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getMemRIEncoding(const MCInst &MI, unsigned OpNo,
+                            SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
+                             SmallVectorImpl<MCFixup> &Fixups) const;
+  unsigned get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
+                               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;
+  
+  // getBinaryCodeForInstr - TableGen'erated function for getting the
+  // binary encoding for an instruction.
+  unsigned getBinaryCodeForInstr(const MCInst &MI,
+                                 SmallVectorImpl<MCFixup> &Fixups) const;
+  void 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.
+  }
+  
+};
+  
+} // end anonymous namespace
+  
+MCCodeEmitter *llvm::createPPCMCCodeEmitter(const MCInstrInfo &MCII,
+                                            const MCSubtargetInfo &STI,
+                                            MCContext &Ctx) {
+  return new PPCMCCodeEmitter(MCII, STI, Ctx);
+}
+
+unsigned PPCMCCodeEmitter::
+getDirectBrEncoding(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);
+  
+  // Add a fixup for the branch target.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_br24));
+  return 0;
+}
+
+unsigned PPCMCCodeEmitter::getCondBrEncoding(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);
+
+  // Add a fixup for the branch target.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_brcond14));
+  return 0;
+}
+
+unsigned PPCMCCodeEmitter::getHA16Encoding(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);
+  
+  // Add a fixup for the branch target.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_ha16));
+  return 0;
+}
+
+unsigned PPCMCCodeEmitter::getLO16Encoding(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);
+  
+  // Add a fixup for the branch target.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_lo16));
+  return 0;
+}
+
+unsigned PPCMCCodeEmitter::getMemRIEncoding(const MCInst &MI, unsigned OpNo,
+                                            SmallVectorImpl<MCFixup> &Fixups) const {
+  // Encode (imm, reg) as a memri, which has the low 16-bits as the
+  // displacement and the next 5 bits as the register #.
+  assert(MI.getOperand(OpNo+1).isReg());
+  unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups) << 16;
+  
+  const MCOperand &MO = MI.getOperand(OpNo);
+  if (MO.isImm())
+    return (getMachineOpValue(MI, MO, Fixups) & 0xFFFF) | RegBits;
+  
+  // Add a fixup for the displacement field.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_lo16));
+  return RegBits;
+}
+
+
+unsigned PPCMCCodeEmitter::getMemRIXEncoding(const MCInst &MI, unsigned OpNo,
+                                       SmallVectorImpl<MCFixup> &Fixups) const {
+  // Encode (imm, reg) as a memrix, which has the low 14-bits as the
+  // displacement and the next 5 bits as the register #.
+  assert(MI.getOperand(OpNo+1).isReg());
+  unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo+1), Fixups) << 14;
+  
+  const MCOperand &MO = MI.getOperand(OpNo);
+  if (MO.isImm())
+    return (getMachineOpValue(MI, MO, Fixups) & 0x3FFF) | RegBits;
+  
+  // Add a fixup for the branch target.
+  Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
+                                   (MCFixupKind)PPC::fixup_ppc_lo14));
+  return RegBits;
+}
+
+
+unsigned PPCMCCodeEmitter::
+get_crbitm_encoding(const MCInst &MI, unsigned OpNo,
+                    SmallVectorImpl<MCFixup> &Fixups) const {
+  const MCOperand &MO = MI.getOperand(OpNo);
+  assert((MI.getOpcode() == PPC::MTCRF || MI.getOpcode() == PPC::MFOCRF) &&
+         (MO.getReg() >= PPC::CR0 && MO.getReg() <= PPC::CR7));
+  return 0x80 >> getPPCRegisterNumbering(MO.getReg());
+}
+
+
+unsigned PPCMCCodeEmitter::
+getMachineOpValue(const MCInst &MI, const MCOperand &MO,
+                  SmallVectorImpl<MCFixup> &Fixups) const {
+  if (MO.isReg()) {
+    // MTCRF/MFOCRF should go through get_crbitm_encoding for the CR operand.
+    // The GPR operand should come through here though.
+    assert((MI.getOpcode() != PPC::MTCRF && MI.getOpcode() != PPC::MFOCRF) ||
+           MO.getReg() < PPC::CR0 || MO.getReg() > PPC::CR7);
+    return getPPCRegisterNumbering(MO.getReg());
+  }
+  
+  assert(MO.isImm() &&
+         "Relocation required in an instruction that we cannot encode!");
+  return MO.getImm();
+}
+
+
+#include "PPCGenMCCodeEmitter.inc"