Implement MipsTargetLowering::CanLowerReturn.
[oota-llvm.git] / lib / Target / Sparc / SparcInstrInfo.cpp
index 7ede8e7ebbe469148e4b8ae5012e23aa1aae5fb9..f8674d0bd660fb8b73f0d33448332b26e9430e69 100644 (file)
@@ -1,4 +1,4 @@
-//===- SparcInstrInfo.cpp - Sparc Instruction Information -------*- C++ -*-===//
+//===-- SparcInstrInfo.cpp - Sparc Instruction Information ----------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 //===----------------------------------------------------------------------===//
 
 #include "SparcInstrInfo.h"
-#include "SparcSubtarget.h"
 #include "Sparc.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallVector.h"
+#include "SparcMachineFunctionInfo.h"
+#include "SparcSubtarget.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+
+#define GET_INSTRINFO_CTOR
 #include "SparcGenInstrInfo.inc"
-#include "SparcMachineFunctionInfo.h"
+
 using namespace llvm;
 
 SparcInstrInfo::SparcInstrInfo(SparcSubtarget &ST)
-  : TargetInstrInfoImpl(SparcInsts, array_lengthof(SparcInsts)),
+  : SparcGenInstrInfo(SP::ADJCALLSTACKDOWN, SP::ADJCALLSTACKUP),
     RI(ST, *this), Subtarget(ST) {
 }
 
@@ -66,15 +70,211 @@ unsigned SparcInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
   return 0;
 }
 
+static bool IsIntegerCC(unsigned CC)
+{
+  return  (CC <= SPCC::ICC_VC);
+}
+
+
+static SPCC::CondCodes GetOppositeBranchCondition(SPCC::CondCodes CC)
+{
+  switch(CC) {
+  case SPCC::ICC_NE:   return SPCC::ICC_E;
+  case SPCC::ICC_E:    return SPCC::ICC_NE;
+  case SPCC::ICC_G:    return SPCC::ICC_LE;
+  case SPCC::ICC_LE:   return SPCC::ICC_G;
+  case SPCC::ICC_GE:   return SPCC::ICC_L;
+  case SPCC::ICC_L:    return SPCC::ICC_GE;
+  case SPCC::ICC_GU:   return SPCC::ICC_LEU;
+  case SPCC::ICC_LEU:  return SPCC::ICC_GU;
+  case SPCC::ICC_CC:   return SPCC::ICC_CS;
+  case SPCC::ICC_CS:   return SPCC::ICC_CC;
+  case SPCC::ICC_POS:  return SPCC::ICC_NEG;
+  case SPCC::ICC_NEG:  return SPCC::ICC_POS;
+  case SPCC::ICC_VC:   return SPCC::ICC_VS;
+  case SPCC::ICC_VS:   return SPCC::ICC_VC;
+
+  case SPCC::FCC_U:    return SPCC::FCC_O;
+  case SPCC::FCC_O:    return SPCC::FCC_U;
+  case SPCC::FCC_G:    return SPCC::FCC_LE;
+  case SPCC::FCC_LE:   return SPCC::FCC_G;
+  case SPCC::FCC_UG:   return SPCC::FCC_ULE;
+  case SPCC::FCC_ULE:  return SPCC::FCC_UG;
+  case SPCC::FCC_L:    return SPCC::FCC_GE;
+  case SPCC::FCC_GE:   return SPCC::FCC_L;
+  case SPCC::FCC_UL:   return SPCC::FCC_UGE;
+  case SPCC::FCC_UGE:  return SPCC::FCC_UL;
+  case SPCC::FCC_LG:   return SPCC::FCC_UE;
+  case SPCC::FCC_UE:   return SPCC::FCC_LG;
+  case SPCC::FCC_NE:   return SPCC::FCC_E;
+  case SPCC::FCC_E:    return SPCC::FCC_NE;
+  }
+  llvm_unreachable("Invalid cond code");
+}
+
+MachineInstr *
+SparcInstrInfo::emitFrameIndexDebugValue(MachineFunction &MF,
+                                         int FrameIx,
+                                         uint64_t Offset,
+                                         const MDNode *MDPtr,
+                                         DebugLoc dl) const {
+  MachineInstrBuilder MIB = BuildMI(MF, dl, get(SP::DBG_VALUE))
+    .addFrameIndex(FrameIx).addImm(0).addImm(Offset).addMetadata(MDPtr);
+  return &*MIB;
+}
+
+
+bool SparcInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
+                                   MachineBasicBlock *&TBB,
+                                   MachineBasicBlock *&FBB,
+                                   SmallVectorImpl<MachineOperand> &Cond,
+                                   bool AllowModify) const
+{
+
+  MachineBasicBlock::iterator I = MBB.end();
+  MachineBasicBlock::iterator UnCondBrIter = MBB.end();
+  while (I != MBB.begin()) {
+    --I;
+
+    if (I->isDebugValue())
+      continue;
+
+    //When we see a non-terminator, we are done
+    if (!isUnpredicatedTerminator(I))
+      break;
+
+    //Terminator is not a branch
+    if (!I->isBranch())
+      return true;
+
+    //Handle Unconditional branches
+    if (I->getOpcode() == SP::BA) {
+      UnCondBrIter = I;
+
+      if (!AllowModify) {
+        TBB = I->getOperand(0).getMBB();
+        continue;
+      }
+
+      while (llvm::next(I) != MBB.end())
+        llvm::next(I)->eraseFromParent();
+
+      Cond.clear();
+      FBB = 0;
+
+      if (MBB.isLayoutSuccessor(I->getOperand(0).getMBB())) {
+        TBB = 0;
+        I->eraseFromParent();
+        I = MBB.end();
+        UnCondBrIter = MBB.end();
+        continue;
+      }
+
+      TBB = I->getOperand(0).getMBB();
+      continue;
+    }
+
+    unsigned Opcode = I->getOpcode();
+    if (Opcode != SP::BCOND && Opcode != SP::FBCOND)
+      return true; //Unknown Opcode
+
+    SPCC::CondCodes BranchCode = (SPCC::CondCodes)I->getOperand(1).getImm();
+
+    if (Cond.empty()) {
+      MachineBasicBlock *TargetBB = I->getOperand(0).getMBB();
+      if (AllowModify && UnCondBrIter != MBB.end() &&
+          MBB.isLayoutSuccessor(TargetBB)) {
+
+        //Transform the code
+        //
+        //    brCC L1
+        //    ba L2
+        // L1:
+        //    ..
+        // L2:
+        //
+        // into
+        //
+        //   brnCC L2
+        // L1:
+        //   ...
+        // L2:
+        //
+        BranchCode = GetOppositeBranchCondition(BranchCode);
+        MachineBasicBlock::iterator OldInst = I;
+        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(Opcode))
+          .addMBB(UnCondBrIter->getOperand(0).getMBB()).addImm(BranchCode);
+        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(SP::BA))
+          .addMBB(TargetBB);
+
+        OldInst->eraseFromParent();
+        UnCondBrIter->eraseFromParent();
+
+        UnCondBrIter = MBB.end();
+        I = MBB.end();
+        continue;
+      }
+      FBB = TBB;
+      TBB = I->getOperand(0).getMBB();
+      Cond.push_back(MachineOperand::CreateImm(BranchCode));
+      continue;
+    }
+    //FIXME: Handle subsequent conditional branches
+    //For now, we can't handle multiple conditional branches
+    return true;
+  }
+  return false;
+}
+
 unsigned
 SparcInstrInfo::InsertBranch(MachineBasicBlock &MBB,MachineBasicBlock *TBB,
                              MachineBasicBlock *FBB,
                              const SmallVectorImpl<MachineOperand> &Cond,
-                             DebugLoc DL)const{
-  // Can only insert uncond branches so far.
-  assert(Cond.empty() && !FBB && TBB && "Can only handle uncond branches!");
-  BuildMI(&MBB, DL, get(SP::BA)).addMBB(TBB);
-  return 1;
+                             DebugLoc DL) const {
+  assert(TBB && "InsertBranch must not be told to insert a fallthrough");
+  assert((Cond.size() == 1 || Cond.size() == 0) &&
+         "Sparc branch conditions should have one component!");
+
+  if (Cond.empty()) {
+    assert(!FBB && "Unconditional branch with multiple successors!");
+    BuildMI(&MBB, DL, get(SP::BA)).addMBB(TBB);
+    return 1;
+  }
+
+  //Conditional branch
+  unsigned CC = Cond[0].getImm();
+
+  if (IsIntegerCC(CC))
+    BuildMI(&MBB, DL, get(SP::BCOND)).addMBB(TBB).addImm(CC);
+  else
+    BuildMI(&MBB, DL, get(SP::FBCOND)).addMBB(TBB).addImm(CC);
+  if (!FBB)
+    return 1;
+
+  BuildMI(&MBB, DL, get(SP::BA)).addMBB(FBB);
+  return 2;
+}
+
+unsigned SparcInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const
+{
+  MachineBasicBlock::iterator I = MBB.end();
+  unsigned Count = 0;
+  while (I != MBB.begin()) {
+    --I;
+
+    if (I->isDebugValue())
+      continue;
+
+    if (I->getOpcode() != SP::BA
+        && I->getOpcode() != SP::BCOND
+        && I->getOpcode() != SP::FBCOND)
+      break; // Not a branch
+
+    I->eraseFromParent();
+    I = MBB.end();
+    ++Count;
+  }
+  return Count;
 }
 
 void SparcInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
@@ -103,13 +303,13 @@ storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
   if (I != MBB.end()) DL = I->getDebugLoc();
 
   // On the order of operands here: think "[FrameIdx + 0] = SrcReg".
-  if (RC == SP::IntRegsRegisterClass)
+  if (RC == &SP::IntRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::STri)).addFrameIndex(FI).addImm(0)
       .addReg(SrcReg, getKillRegState(isKill));
-  else if (RC == SP::FPRegsRegisterClass)
+  else if (RC == &SP::FPRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::STFri)).addFrameIndex(FI).addImm(0)
       .addReg(SrcReg,  getKillRegState(isKill));
-  else if (RC == SP::DFPRegsRegisterClass)
+  else if (RC == &SP::DFPRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::STDFri)).addFrameIndex(FI).addImm(0)
       .addReg(SrcReg,  getKillRegState(isKill));
   else
@@ -124,11 +324,11 @@ loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
   DebugLoc DL;
   if (I != MBB.end()) DL = I->getDebugLoc();
 
-  if (RC == SP::IntRegsRegisterClass)
+  if (RC == &SP::IntRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::LDri), DestReg).addFrameIndex(FI).addImm(0);
-  else if (RC == SP::FPRegsRegisterClass)
+  else if (RC == &SP::FPRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::LDFri), DestReg).addFrameIndex(FI).addImm(0);
-  else if (RC == SP::DFPRegsRegisterClass)
+  else if (RC == &SP::DFPRegsRegClass)
     BuildMI(MBB, I, DL, get(SP::LDDFri), DestReg).addFrameIndex(FI).addImm(0);
   else
     llvm_unreachable("Can't load this register from stack slot");