Checkpoint refactoring of ThumbInstrInfo and ThumbRegisterInfo into Thumb1InstrInfo, Thumb2InstrInfo, Thumb1RegisterInfo and Thumb2RegisterInfo. Move methods from ARMInstrInfo to ARMBaseInstrInfo to prepare for sharing with Thumb2.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74731 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/Thumb1InstrInfo.cpp b/lib/Target/ARM/Thumb1InstrInfo.cpp
new file mode 100644
index 0000000..e13a811
--- /dev/null
+++ b/lib/Target/ARM/Thumb1InstrInfo.cpp
@@ -0,0 +1,304 @@
+//===- Thumb1InstrInfo.cpp - Thumb-1 Instruction Information --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the Thumb-1 implementation of the TargetInstrInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARMInstrInfo.h"
+#include "ARM.h"
+#include "ARMGenInstrInfo.inc"
+#include "ARMMachineFunctionInfo.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/ADT/SmallVector.h"
+#include "Thumb1InstrInfo.h"
+
+using namespace llvm;
+
+Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI)
+  : ARMBaseInstrInfo(STI), RI(*this, STI) {
+}
+
+bool Thumb1InstrInfo::isMoveInstr(const MachineInstr &MI,
+                                  unsigned &SrcReg, unsigned &DstReg,
+                                  unsigned& SrcSubIdx, unsigned& DstSubIdx) const {
+  SrcSubIdx = DstSubIdx = 0; // No sub-registers.
+
+  unsigned oc = MI.getOpcode();
+  switch (oc) {
+  default:
+    return false;
+  case ARM::tMOVr:
+  case ARM::tMOVhir2lor:
+  case ARM::tMOVlor2hir:
+  case ARM::tMOVhir2hir:
+    assert(MI.getDesc().getNumOperands() >= 2 &&
+           MI.getOperand(0).isReg() &&
+           MI.getOperand(1).isReg() &&
+           "Invalid Thumb MOV instruction");
+    SrcReg = MI.getOperand(1).getReg();
+    DstReg = MI.getOperand(0).getReg();
+    return true;
+  }
+}
+
+unsigned Thumb1InstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
+                                              int &FrameIndex) const {
+  switch (MI->getOpcode()) {
+  default: break;
+  case ARM::tRestore:
+    if (MI->getOperand(1).isFI() &&
+        MI->getOperand(2).isImm() &&
+        MI->getOperand(2).getImm() == 0) {
+      FrameIndex = MI->getOperand(1).getIndex();
+      return MI->getOperand(0).getReg();
+    }
+    break;
+  }
+  return 0;
+}
+
+unsigned Thumb1InstrInfo::isStoreToStackSlot(const MachineInstr *MI,
+                                             int &FrameIndex) const {
+  switch (MI->getOpcode()) {
+  default: break;
+  case ARM::tSpill:
+    if (MI->getOperand(1).isFI() &&
+        MI->getOperand(2).isImm() &&
+        MI->getOperand(2).getImm() == 0) {
+      FrameIndex = MI->getOperand(1).getIndex();
+      return MI->getOperand(0).getReg();
+    }
+    break;
+  }
+  return 0;
+}
+
+bool Thumb1InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
+                                   MachineBasicBlock::iterator I,
+                                   unsigned DestReg, unsigned SrcReg,
+                                   const TargetRegisterClass *DestRC,
+                                   const TargetRegisterClass *SrcRC) const {
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  if (I != MBB.end()) DL = I->getDebugLoc();
+
+  if (DestRC == ARM::GPRRegisterClass) {
+    if (SrcRC == ARM::GPRRegisterClass) {
+      BuildMI(MBB, I, DL, get(ARM::tMOVhir2hir), DestReg).addReg(SrcReg);
+      return true;
+    } else if (SrcRC == ARM::tGPRRegisterClass) {
+      BuildMI(MBB, I, DL, get(ARM::tMOVlor2hir), DestReg).addReg(SrcReg);
+      return true;
+    }
+  } else if (DestRC == ARM::tGPRRegisterClass) {
+    if (SrcRC == ARM::GPRRegisterClass) {
+      BuildMI(MBB, I, DL, get(ARM::tMOVhir2lor), DestReg).addReg(SrcReg);
+      return true;
+    } else if (SrcRC == ARM::tGPRRegisterClass) {
+      BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool Thumb1InstrInfo::
+canFoldMemoryOperand(const MachineInstr *MI,
+                     const SmallVectorImpl<unsigned> &Ops) const {
+  if (Ops.size() != 1) return false;
+
+  unsigned OpNum = Ops[0];
+  unsigned Opc = MI->getOpcode();
+  switch (Opc) {
+  default: break;
+  case ARM::tMOVr:
+  case ARM::tMOVlor2hir:
+  case ARM::tMOVhir2lor:
+  case ARM::tMOVhir2hir: {
+    if (OpNum == 0) { // move -> store
+      unsigned SrcReg = MI->getOperand(1).getReg();
+      if (RI.isPhysicalRegister(SrcReg) && !isARMLowRegister(SrcReg))
+        // tSpill cannot take a high register operand.
+        return false;
+    } else {          // move -> load
+      unsigned DstReg = MI->getOperand(0).getReg();
+      if (RI.isPhysicalRegister(DstReg) && !isARMLowRegister(DstReg))
+        // tRestore cannot target a high register operand.
+        return false;
+    }
+    return true;
+  }
+  }
+
+  return false;
+}
+
+void Thumb1InstrInfo::
+storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+                    unsigned SrcReg, bool isKill, int FI,
+                    const TargetRegisterClass *RC) const {
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  if (I != MBB.end()) DL = I->getDebugLoc();
+
+  assert(RC == ARM::tGPRRegisterClass && "Unknown regclass!");
+
+  if (RC == ARM::tGPRRegisterClass) {
+    BuildMI(MBB, I, DL, get(ARM::tSpill))
+      .addReg(SrcReg, getKillRegState(isKill))
+      .addFrameIndex(FI).addImm(0);
+  }
+}
+
+void Thumb1InstrInfo::storeRegToAddr(MachineFunction &MF, unsigned SrcReg,
+                                     bool isKill,
+                                     SmallVectorImpl<MachineOperand> &Addr,
+                                     const TargetRegisterClass *RC,
+                                     SmallVectorImpl<MachineInstr*> &NewMIs) const{
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  unsigned Opc = 0;
+
+  assert(RC == ARM::GPRRegisterClass && "Unknown regclass!");
+  if (RC == ARM::GPRRegisterClass) {
+    Opc = Addr[0].isFI() ? ARM::tSpill : ARM::tSTR;
+  }
+
+  MachineInstrBuilder MIB =
+    BuildMI(MF, DL,  get(Opc)).addReg(SrcReg, getKillRegState(isKill));
+  for (unsigned i = 0, e = Addr.size(); i != e; ++i)
+    MIB.addOperand(Addr[i]);
+  NewMIs.push_back(MIB);
+  return;
+}
+
+void Thumb1InstrInfo::
+loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+                     unsigned DestReg, int FI,
+                     const TargetRegisterClass *RC) const {
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  if (I != MBB.end()) DL = I->getDebugLoc();
+
+  assert(RC == ARM::tGPRRegisterClass && "Unknown regclass!");
+
+  if (RC == ARM::tGPRRegisterClass) {
+    BuildMI(MBB, I, DL, get(ARM::tRestore), DestReg)
+      .addFrameIndex(FI).addImm(0);
+  }
+}
+
+void Thumb1InstrInfo::
+loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
+                SmallVectorImpl<MachineOperand> &Addr,
+                const TargetRegisterClass *RC,
+                SmallVectorImpl<MachineInstr*> &NewMIs) const {
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  unsigned Opc = 0;
+
+  if (RC == ARM::GPRRegisterClass) {
+    Opc = Addr[0].isFI() ? ARM::tRestore : ARM::tLDR;
+  }
+
+  MachineInstrBuilder MIB = BuildMI(MF, DL, get(Opc), DestReg);
+  for (unsigned i = 0, e = Addr.size(); i != e; ++i)
+    MIB.addOperand(Addr[i]);
+  NewMIs.push_back(MIB);
+  return;
+}
+
+bool Thumb1InstrInfo::
+spillCalleeSavedRegisters(MachineBasicBlock &MBB,
+                          MachineBasicBlock::iterator MI,
+                          const std::vector<CalleeSavedInfo> &CSI) const {
+  if (CSI.empty())
+    return false;
+
+  DebugLoc DL = DebugLoc::getUnknownLoc();
+  if (MI != MBB.end()) DL = MI->getDebugLoc();
+
+  MachineInstrBuilder MIB = BuildMI(MBB, MI, DL, get(ARM::tPUSH));
+  for (unsigned i = CSI.size(); i != 0; --i) {
+    unsigned Reg = CSI[i-1].getReg();
+    // Add the callee-saved register as live-in. It's killed at the spill.
+    MBB.addLiveIn(Reg);
+    MIB.addReg(Reg, RegState::Kill);
+  }
+  return true;
+}
+
+bool Thumb1InstrInfo::
+restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
+                            MachineBasicBlock::iterator MI,
+                            const std::vector<CalleeSavedInfo> &CSI) const {
+  MachineFunction &MF = *MBB.getParent();
+  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+  if (CSI.empty())
+    return false;
+
+  bool isVarArg = AFI->getVarArgsRegSaveSize() > 0;
+  MachineInstr *PopMI = MF.CreateMachineInstr(get(ARM::tPOP),MI->getDebugLoc());
+  for (unsigned i = CSI.size(); i != 0; --i) {
+    unsigned Reg = CSI[i-1].getReg();
+    if (Reg == ARM::LR) {
+      // Special epilogue for vararg functions. See emitEpilogue
+      if (isVarArg)
+        continue;
+      Reg = ARM::PC;
+      PopMI->setDesc(get(ARM::tPOP_RET));
+      MI = MBB.erase(MI);
+    }
+    PopMI->addOperand(MachineOperand::CreateReg(Reg, true));
+  }
+
+  // It's illegal to emit pop instruction without operands.
+  if (PopMI->getNumOperands() > 0)
+    MBB.insert(MI, PopMI);
+
+  return true;
+}
+
+MachineInstr *Thumb1InstrInfo::
+foldMemoryOperandImpl(MachineFunction &MF, MachineInstr *MI,
+                      const SmallVectorImpl<unsigned> &Ops, int FI) const {
+  if (Ops.size() != 1) return NULL;
+
+  unsigned OpNum = Ops[0];
+  unsigned Opc = MI->getOpcode();
+  MachineInstr *NewMI = NULL;
+  switch (Opc) {
+  default: break;
+  case ARM::tMOVr:
+  case ARM::tMOVlor2hir:
+  case ARM::tMOVhir2lor:
+  case ARM::tMOVhir2hir: {
+    if (OpNum == 0) { // move -> store
+      unsigned SrcReg = MI->getOperand(1).getReg();
+      bool isKill = MI->getOperand(1).isKill();
+      if (RI.isPhysicalRegister(SrcReg) && !isARMLowRegister(SrcReg))
+        // tSpill cannot take a high register operand.
+        break;
+      NewMI = BuildMI(MF, MI->getDebugLoc(), get(ARM::tSpill))
+        .addReg(SrcReg, getKillRegState(isKill))
+        .addFrameIndex(FI).addImm(0);
+    } else {          // move -> load
+      unsigned DstReg = MI->getOperand(0).getReg();
+      if (RI.isPhysicalRegister(DstReg) && !isARMLowRegister(DstReg))
+        // tRestore cannot target a high register operand.
+        break;
+      bool isDead = MI->getOperand(0).isDead();
+      NewMI = BuildMI(MF, MI->getDebugLoc(), get(ARM::tRestore))
+        .addReg(DstReg, RegState::Define | getDeadRegState(isDead))
+        .addFrameIndex(FI).addImm(0);
+    }
+    break;
+  }
+  }
+
+  return NewMI;
+}