[X86] Initial cleanups on the FixupLEAs pass. Separate Atom LEA creation from other LEA optimizations.

[craig.topper]

Summary

This removes some of the class variables. Merge basic block processing into
runOnMachineFunction to keep the flags local.

Pass MachineBasicBlock around instead of an iterator. We can get the iterator in
the few places that need it. Allows a range-based outer for loop.

Separate the Atom optimization from the rest of the optimizations. This allows
fixupIncDec to create INC/DEC and still allow Atom to turn it back into LEA
when profitable by its heuristics.

I'd like to improve fixupIncDec to turn LEAs into ADD any time the base or index
register is equal to the destination register. This is profitable regardless of
the various slow flags. But again we would want Atom to be able to undo that.

[craig.topper]

llvm/test/CodeGen/X86/lsr-static-addr.ll

40 ↗

(On Diff #196183)

Forgot to mention. This change is specifically because the OptIncDec code was creating an INC here and preventing Atom from visiting it due to the continue.

[RKSimon]

llvm/test/CodeGen/X86/lsr-static-addr.ll

40 ↗

(On Diff #196183)

Please can you regenerate this against trunk?

[craig.topper]

Rebase after precommitting test autogeneration.

[craig.topper]

Ping

[andreadb]

LGTM

llvm/trunk/lib/Target/X86/X86FixupLEAs.cpp

 #define DEBUG_TYPE FIXUPLEA_NAME
 
 STATISTIC(NumLEAs, "Number of LEA instructions created");
 
 namespace {
 class FixupLEAPass : public MachineFunctionPass {
   enum RegUsageState { RU_NotUsed, RU_Write, RU_Read };
 
-  /// Loop over all of the instructions in the basic block
-  /// replacing applicable instructions with LEA instructions,
-  /// where appropriate.
-  bool processBasicBlock(MachineFunction &MF, MachineFunction::iterator MFI,
-                         bool IsSlowLEA, bool IsSlow3OpsLEA);
-
   /// Given a machine register, look for the instruction
   /// which writes it in the current basic block. If found,
   /// try to replace it with an equivalent LEA instruction.
   /// If replacement succeeds, then also process the newly created
   /// instruction.
   void seekLEAFixup(MachineOperand &p, MachineBasicBlock::iterator &I,
-                    MachineFunction::iterator MFI);
+                    MachineBasicBlock &MBB);
 
   /// Given a memory access or LEA instruction
   /// whose address mode uses a base and/or index register, look for
   /// an opportunity to replace the instruction which sets the base or index
   /// register with an equivalent LEA instruction.
   void processInstruction(MachineBasicBlock::iterator &I,
-                          MachineFunction::iterator MFI);
+                          MachineBasicBlock &MBB);
 
   /// Given a LEA instruction which is unprofitable
   /// on SlowLEA targets try to replace it with an equivalent ADD instruction.
   void processInstructionForSlowLEA(MachineBasicBlock::iterator &I,
-                                    MachineFunction::iterator MFI);
+                                    MachineBasicBlock &MBB);
 
   /// Given a LEA instruction which is unprofitable
   /// on SNB+ try to replace it with other instructions.
   /// According to Intel's Optimization Reference Manual:
   /// " For LEA instructions with three source operands and some specific
   ///   situations, instruction latency has increased to 3 cycles, and must
   ///   dispatch via port 1:
   /// - LEA that has all three source operands: base, index, and offset
   /// - LEA that uses base and index registers where the base is EBP, RBP,
   ///   or R13
   /// - LEA that uses RIP relative addressing mode
   /// - LEA that uses 16-bit addressing mode "
   /// This function currently handles the first 2 cases only.
   MachineInstr *processInstrForSlow3OpLEA(MachineInstr &MI,
-                                          MachineFunction::iterator MFI);
+                                          MachineBasicBlock &MBB);
 
   /// Look for LEAs that add 1 to reg or subtract 1 from reg
   /// and convert them to INC or DEC respectively.
   bool fixupIncDec(MachineBasicBlock::iterator &I,
-                   MachineFunction::iterator MFI) const;
+                   MachineBasicBlock &MBB) const;
 
   /// Determine if an instruction references a machine register
   /// and, if so, whether it reads or writes the register.
   RegUsageState usesRegister(MachineOperand &p, MachineBasicBlock::iterator I);
 
   /// Step backwards through a basic block, looking
   /// for an instruction which writes a register within
   /// a maximum of INSTR_DISTANCE_THRESHOLD instruction latency cycles.
   MachineBasicBlock::iterator searchBackwards(MachineOperand &p,
                                               MachineBasicBlock::iterator &I,
-                                              MachineFunction::iterator MFI);
+                                              MachineBasicBlock &MBB);
 
   /// if an instruction can be converted to an
   /// equivalent LEA, insert the new instruction into the basic block
   /// and return a pointer to it. Otherwise, return zero.
-  MachineInstr *postRAConvertToLEA(MachineFunction::iterator &MFI,
+  MachineInstr *postRAConvertToLEA(MachineBasicBlock &MBB,
                                    MachineBasicBlock::iterator &MBBI) const;
 
 public:
   static char ID;
 
   StringRef getPassName() const override { return FIXUPLEA_DESC; }
 
   FixupLEAPass() : MachineFunctionPass(ID) {
     initializeFixupLEAPassPass(*PassRegistry::getPassRegistry());
   }
 
   /// Loop over all of the basic blocks,
   /// replacing instructions by equivalent LEA instructions
   /// if needed and when possible.
   bool runOnMachineFunction(MachineFunction &MF) override;
 
   // This pass runs after regalloc and doesn't support VReg operands.
   MachineFunctionProperties getRequiredProperties() const override {
     return MachineFunctionProperties().set(
         MachineFunctionProperties::Property::NoVRegs);
   }
 
 private:
   TargetSchedModel TSM;
-  MachineFunction *MF;
   const X86InstrInfo *TII; // Machine instruction info.
-  bool OptIncDec;
-  bool OptLEA;
 };
 }
 
 char FixupLEAPass::ID = 0;
 
 INITIALIZE_PASS(FixupLEAPass, FIXUPLEA_NAME, FIXUPLEA_DESC, false, false)
 
 MachineInstr *
-FixupLEAPass::postRAConvertToLEA(MachineFunction::iterator &MFI,
+FixupLEAPass::postRAConvertToLEA(MachineBasicBlock &MBB,
                                  MachineBasicBlock::iterator &MBBI) const {
   MachineInstr &MI = *MBBI;
   switch (MI.getOpcode()) {
   case X86::MOV32rr:
   case X86::MOV64rr: {
     const MachineOperand &Src = MI.getOperand(1);
     const MachineOperand &Dest = MI.getOperand(0);
     MachineInstr *NewMI =
-        BuildMI(*MF, MI.getDebugLoc(),
+        BuildMI(MBB, MBBI, MI.getDebugLoc(),
                 TII->get(MI.getOpcode() == X86::MOV32rr ? X86::LEA32r
                                                         : X86::LEA64r))
             .add(Dest)
             .add(Src)
             .addImm(1)
             .addReg(0)
             .addImm(0)
             .addReg(0);
-    MFI->insert(MBBI, NewMI); // Insert the new inst
     return NewMI;
   }
   }
 
   if (!MI.isConvertibleTo3Addr())
     return nullptr;
 
   switch (MI.getOpcode()) {
FixupLEAPass::postRAConvertToLEA(MachineBasicBlock &MBB,
   case X86::ADD16rr_DB:
     if (MI.getOperand(1).getReg() != MI.getOperand(2).getReg()) {
       // if src1 != src2, then convertToThreeAddress will
       // need to create a Virtual register, which we cannot do
       // after register allocation.
       return nullptr;
     }
   }
+  MachineFunction::iterator MFI = MBB.getIterator();
   return TII->convertToThreeAddress(MFI, MI, nullptr);
 }
 
 FunctionPass *llvm::createX86FixupLEAs() { return new FixupLEAPass(); }
 
-bool FixupLEAPass::runOnMachineFunction(MachineFunction &Func) {
-  if (skipFunction(Func.getFunction()))
+bool FixupLEAPass::runOnMachineFunction(MachineFunction &MF) {
+  if (skipFunction(MF.getFunction()))
     return false;
 
-  MF = &Func;
-  const X86Subtarget &ST = Func.getSubtarget<X86Subtarget>();
+  const X86Subtarget &ST = MF.getSubtarget<X86Subtarget>();
   bool IsSlowLEA = ST.slowLEA();
   bool IsSlow3OpsLEA = ST.slow3OpsLEA();
+  bool LEAUsesAG = ST.LEAusesAG();
 
-  OptIncDec = !ST.slowIncDec() || Func.getFunction().hasOptSize();
-  OptLEA = ST.LEAusesAG() || IsSlowLEA || IsSlow3OpsLEA;
+  bool OptIncDec = !ST.slowIncDec() || MF.getFunction().hasOptSize();
+  bool OptLEA = LEAUsesAG || IsSlowLEA || IsSlow3OpsLEA;
 
   if (!OptLEA && !OptIncDec)
     return false;
 
-  TSM.init(&Func.getSubtarget());
+  TSM.init(&ST);
   TII = ST.getInstrInfo();
 
   LLVM_DEBUG(dbgs() << "Start X86FixupLEAs\n";);
-  // Process all basic blocks.
-  for (MachineFunction::iterator I = Func.begin(), E = Func.end(); I != E; ++I)
-    processBasicBlock(Func, I, IsSlowLEA, IsSlow3OpsLEA);
+  for (MachineBasicBlock &MBB : MF) {
+    // First pass. Try to remove or optimize existing LEAs.
+    for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ++I) {
+      if (OptIncDec && fixupIncDec(I, MBB))
+        continue;
+
+      if (IsSlowLEA) {
+        processInstructionForSlowLEA(I, MBB);
+      } else if (IsSlow3OpsLEA) {
+        if (auto *NewMI = processInstrForSlow3OpLEA(*I, MBB)) {
+          MBB.erase(I);
+          I = NewMI;
+        }
+      }
+    }
+
+    // Second pass for creating LEAs. This may reverse some of the
+    // transformations above.
+    if (LEAUsesAG) {
+      for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ++I)
+        processInstruction(I, MBB);
+    }
+  }
+
   LLVM_DEBUG(dbgs() << "End X86FixupLEAs\n";);
 
   return true;
 }
 
 FixupLEAPass::RegUsageState
 FixupLEAPass::usesRegister(MachineOperand &p, MachineBasicBlock::iterator I) {
   RegUsageState RegUsage = RU_NotUsed;
FixupLEAPass::usesRegister(MachineOperand &p, MachineBasicBlock::iterator I) {
   return RegUsage;
 }
 
 /// getPreviousInstr - Given a reference to an instruction in a basic
 /// block, return a reference to the previous instruction in the block,
 /// wrapping around to the last instruction of the block if the block
 /// branches to itself.
 static inline bool getPreviousInstr(MachineBasicBlock::iterator &I,
-                                    MachineFunction::iterator MFI) {
-  if (I == MFI->begin()) {
-    if (MFI->isPredecessor(&*MFI)) {
-      I = --MFI->end();
+                                    MachineBasicBlock &MBB) {
+  if (I == MBB.begin()) {
+    if (MBB.isPredecessor(&MBB)) {
+      I = --MBB.end();
       return true;
     } else
       return false;
   }
   --I;
   return true;
 }
 
 MachineBasicBlock::iterator
 FixupLEAPass::searchBackwards(MachineOperand &p, MachineBasicBlock::iterator &I,
-                              MachineFunction::iterator MFI) {
+                              MachineBasicBlock &MBB) {
   int InstrDistance = 1;
   MachineBasicBlock::iterator CurInst;
   static const int INSTR_DISTANCE_THRESHOLD = 5;
 
   CurInst = I;
   bool Found;
-  Found = getPreviousInstr(CurInst, MFI);
+  Found = getPreviousInstr(CurInst, MBB);
   while (Found && I != CurInst) {
     if (CurInst->isCall() || CurInst->isInlineAsm())
       break;
     if (InstrDistance > INSTR_DISTANCE_THRESHOLD)
       break; // too far back to make a difference
     if (usesRegister(p, CurInst) == RU_Write) {
       return CurInst;
     }
     InstrDistance += TSM.computeInstrLatency(&*CurInst);
-    Found = getPreviousInstr(CurInst, MFI);
+    Found = getPreviousInstr(CurInst, MBB);
   }
   return MachineBasicBlock::iterator();
 }
 
 static inline bool isLEA(const unsigned Opcode) {
   return Opcode == X86::LEA16r || Opcode == X86::LEA32r ||
          Opcode == X86::LEA64r || Opcode == X86::LEA64_32r;
 }
static inline bool isLEASimpleIncOrDec(MachineInstr &LEA) {
   return SrcReg == DstReg &&
          LEA.getOperand(1 + X86::AddrIndexReg).getReg() == 0 &&
          LEA.getOperand(1 + X86::AddrSegmentReg).getReg() == 0 &&
          AddrDisp.isImm() &&
          (AddrDisp.getImm() == 1 || AddrDisp.getImm() == -1);
 }
 
 bool FixupLEAPass::fixupIncDec(MachineBasicBlock::iterator &I,
-                               MachineFunction::iterator MFI) const {
+                               MachineBasicBlock &MBB) const {
   MachineInstr &MI = *I;
   unsigned Opcode = MI.getOpcode();
   if (!isLEA(Opcode))
     return false;
 
-  if (isLEASimpleIncOrDec(MI) && TII->isSafeToClobberEFLAGS(*MFI, I)) {
+  if (isLEASimpleIncOrDec(MI) && TII->isSafeToClobberEFLAGS(MBB, I)) {
     unsigned NewOpcode;
     bool isINC = MI.getOperand(1 + X86::AddrDisp).getImm() == 1;
     switch (Opcode) {
     case X86::LEA16r:
       NewOpcode = isINC ? X86::INC16r : X86::DEC16r;
       break;
     case X86::LEA32r:
     case X86::LEA64_32r:
       NewOpcode = isINC ? X86::INC32r : X86::DEC32r;
       break;
     case X86::LEA64r:
       NewOpcode = isINC ? X86::INC64r : X86::DEC64r;
       break;
     }
 
     MachineInstr *NewMI =
-        BuildMI(*MFI, I, MI.getDebugLoc(), TII->get(NewOpcode))
+        BuildMI(MBB, I, MI.getDebugLoc(), TII->get(NewOpcode))
             .add(MI.getOperand(0))
             .add(MI.getOperand(1 + X86::AddrBaseReg));
-    MFI->erase(I);
+    MBB.erase(I);
     I = static_cast<MachineBasicBlock::iterator>(NewMI);
     return true;
   }
   return false;
 }
 
 void FixupLEAPass::processInstruction(MachineBasicBlock::iterator &I,
-                                      MachineFunction::iterator MFI) {
+                                      MachineBasicBlock &MBB) {
   // Process a load, store, or LEA instruction.
   MachineInstr &MI = *I;
   const MCInstrDesc &Desc = MI.getDesc();
   int AddrOffset = X86II::getMemoryOperandNo(Desc.TSFlags);
   if (AddrOffset >= 0) {
     AddrOffset += X86II::getOperandBias(Desc);
     MachineOperand &p = MI.getOperand(AddrOffset + X86::AddrBaseReg);
     if (p.isReg() && p.getReg() != X86::ESP) {
-      seekLEAFixup(p, I, MFI);
+      seekLEAFixup(p, I, MBB);
     }
     MachineOperand &q = MI.getOperand(AddrOffset + X86::AddrIndexReg);
     if (q.isReg() && q.getReg() != X86::ESP) {
-      seekLEAFixup(q, I, MFI);
+      seekLEAFixup(q, I, MBB);
     }
   }
 }
 
 void FixupLEAPass::seekLEAFixup(MachineOperand &p,
                                 MachineBasicBlock::iterator &I,
-                                MachineFunction::iterator MFI) {
-  MachineBasicBlock::iterator MBI = searchBackwards(p, I, MFI);
+                                MachineBasicBlock &MBB) {
+  MachineBasicBlock::iterator MBI = searchBackwards(p, I, MBB);
   if (MBI != MachineBasicBlock::iterator()) {
-    MachineInstr *NewMI = postRAConvertToLEA(MFI, MBI);
+    MachineInstr *NewMI = postRAConvertToLEA(MBB, MBI);
     if (NewMI) {
       ++NumLEAs;
       LLVM_DEBUG(dbgs() << "FixLEA: Candidate to replace:"; MBI->dump(););
       // now to replace with an equivalent LEA...
       LLVM_DEBUG(dbgs() << "FixLEA: Replaced by: "; NewMI->dump(););
-      MFI->erase(MBI);
+      MBB.erase(MBI);
       MachineBasicBlock::iterator J =
           static_cast<MachineBasicBlock::iterator>(NewMI);
-      processInstruction(J, MFI);
+      processInstruction(J, MBB);
     }
   }
 }
 
 void FixupLEAPass::processInstructionForSlowLEA(MachineBasicBlock::iterator &I,
-                                                MachineFunction::iterator MFI) {
+                                                MachineBasicBlock &MBB) {
   MachineInstr &MI = *I;
   const unsigned Opcode = MI.getOpcode();
   if (!isLEA(Opcode))
     return;
 
   const MachineOperand &Dst =     MI.getOperand(0);
   const MachineOperand &Base =    MI.getOperand(1 + X86::AddrBaseReg);
   const MachineOperand &Scale =   MI.getOperand(1 + X86::AddrScaleAmt);
   const MachineOperand &Index =   MI.getOperand(1 + X86::AddrIndexReg);
   const MachineOperand &Offset =  MI.getOperand(1 + X86::AddrDisp);
   const MachineOperand &Segment = MI.getOperand(1 + X86::AddrSegmentReg);
 
   if (Segment.getReg() != 0 || !Offset.isImm() ||
-      !TII->isSafeToClobberEFLAGS(*MFI, I))
+      !TII->isSafeToClobberEFLAGS(MBB, I))
     return;
   const unsigned DstR = Dst.getReg();
   const unsigned SrcR1 = Base.getReg();
   const unsigned SrcR2 = Index.getReg();
   if ((SrcR1 == 0 || SrcR1 != DstR) && (SrcR2 == 0 || SrcR2 != DstR))
     return;
   if (Scale.getImm() > 1)
     return;
   LLVM_DEBUG(dbgs() << "FixLEA: Candidate to replace:"; I->dump(););
   LLVM_DEBUG(dbgs() << "FixLEA: Replaced by: ";);
   MachineInstr *NewMI = nullptr;
   // Make ADD instruction for two registers writing to LEA's destination
   if (SrcR1 != 0 && SrcR2 != 0) {
     const MCInstrDesc &ADDrr = TII->get(getADDrrFromLEA(Opcode));
     const MachineOperand &Src = SrcR1 == DstR ? Index : Base;
     NewMI =
-        BuildMI(*MFI, I, MI.getDebugLoc(), ADDrr, DstR).addReg(DstR).add(Src);
+        BuildMI(MBB, I, MI.getDebugLoc(), ADDrr, DstR).addReg(DstR).add(Src);
     LLVM_DEBUG(NewMI->dump(););
   }
   // Make ADD instruction for immediate
   if (Offset.getImm() != 0) {
     const MCInstrDesc &ADDri =
         TII->get(getADDriFromLEA(Opcode, Offset));
     const MachineOperand &SrcR = SrcR1 == DstR ? Base : Index;
-    NewMI = BuildMI(*MFI, I, MI.getDebugLoc(), ADDri, DstR)
+    NewMI = BuildMI(MBB, I, MI.getDebugLoc(), ADDri, DstR)
                 .add(SrcR)
                 .addImm(Offset.getImm());
     LLVM_DEBUG(NewMI->dump(););
   }
   if (NewMI) {
-    MFI->erase(I);
+    MBB.erase(I);
     I = NewMI;
   }
 }
 
 MachineInstr *
 FixupLEAPass::processInstrForSlow3OpLEA(MachineInstr &MI,
-                                        MachineFunction::iterator MFI) {
+                                        MachineBasicBlock &MBB) {
 
   const unsigned LEAOpcode = MI.getOpcode();
   if (!isLEA(LEAOpcode))
     return nullptr;
 
   const MachineOperand &Dst =     MI.getOperand(0);
   const MachineOperand &Base =    MI.getOperand(1 + X86::AddrBaseReg);
   const MachineOperand &Scale =   MI.getOperand(1 + X86::AddrScaleAmt);
   const MachineOperand &Index =   MI.getOperand(1 + X86::AddrIndexReg);
   const MachineOperand &Offset =  MI.getOperand(1 + X86::AddrDisp);
   const MachineOperand &Segment = MI.getOperand(1 + X86::AddrSegmentReg);
 
   if (!(TII->isThreeOperandsLEA(MI) ||
         hasInefficientLEABaseReg(Base, Index)) ||
-      !TII->isSafeToClobberEFLAGS(*MFI, MI) ||
+      !TII->isSafeToClobberEFLAGS(MBB, MI) ||
       Segment.getReg() != X86::NoRegister)
     return nullptr;
 
   unsigned DstR = Dst.getReg();
   unsigned BaseR = Base.getReg();
   unsigned IndexR = Index.getReg();
   unsigned SSDstR =
       (LEAOpcode == X86::LEA64_32r) ? getX86SubSuperRegister(DstR, 64) : DstR;
FixupLEAPass::processInstrForSlow3OpLEA(MachineInstr &MI,
 
   // First try to replace LEA with one or two (for the 3-op LEA case)
   // add instructions:
   // 1.lea (%base,%index,1), %base => add %index,%base
   // 2.lea (%base,%index,1), %index => add %base,%index
   if (IsScale1 && (DstR == BaseR || DstR == IndexR)) {
     const MachineOperand &Src = DstR == BaseR ? Index : Base;
     MachineInstr *NewMI =
-        BuildMI(*MFI, MI, DL, ADDrr, DstR).addReg(DstR).add(Src);
+        BuildMI(MBB, MI, DL, ADDrr, DstR).addReg(DstR).add(Src);
     LLVM_DEBUG(NewMI->dump(););
     // Create ADD instruction for the Offset in case of 3-Ops LEA.
     if (hasLEAOffset(Offset)) {
-      NewMI = BuildMI(*MFI, MI, DL, ADDri, DstR).addReg(DstR).add(Offset);
+      NewMI = BuildMI(MBB, MI, DL, ADDri, DstR).addReg(DstR).add(Offset);
       LLVM_DEBUG(NewMI->dump(););
     }
     return NewMI;
   }
   // If the base is inefficient try switching the index and base operands,
   // otherwise just break the 3-Ops LEA inst into 2-Ops LEA + ADD instruction:
   // lea offset(%base,%index,scale),%dst =>
   // lea (%base,%index,scale); add offset,%dst
   if (!IsInefficientBase || (!IsInefficientIndex && IsScale1)) {
-    MachineInstr *NewMI = BuildMI(*MFI, MI, DL, TII->get(LEAOpcode))
+    MachineInstr *NewMI = BuildMI(MBB, MI, DL, TII->get(LEAOpcode))
                               .add(Dst)
                               .add(IsInefficientBase ? Index : Base)
                               .add(Scale)
                               .add(IsInefficientBase ? Base : Index)
                               .addImm(0)
                               .add(Segment);
     LLVM_DEBUG(NewMI->dump(););
     // Create ADD instruction for the Offset in case of 3-Ops LEA.
     if (hasLEAOffset(Offset)) {
-      NewMI = BuildMI(*MFI, MI, DL, ADDri, DstR).addReg(DstR).add(Offset);
+      NewMI = BuildMI(MBB, MI, DL, ADDri, DstR).addReg(DstR).add(Offset);
       LLVM_DEBUG(NewMI->dump(););
     }
     return NewMI;
   }
   // Handle the rest of the cases with inefficient base register:
   assert(SSDstR != BaseR && "SSDstR == BaseR should be handled already!");
   assert(IsInefficientBase && "efficient base should be handled already!");
 
   // lea (%base,%index,1), %dst => mov %base,%dst; add %index,%dst
   if (IsScale1 && !hasLEAOffset(Offset)) {
     bool BIK = Base.isKill() && BaseR != IndexR;
-    TII->copyPhysReg(*MFI, MI, DL, DstR, BaseR, BIK);
+    TII->copyPhysReg(MBB, MI, DL, DstR, BaseR, BIK);
     LLVM_DEBUG(MI.getPrevNode()->dump(););
 
     MachineInstr *NewMI =
-        BuildMI(*MFI, MI, DL, ADDrr, DstR).addReg(DstR).add(Index);
+        BuildMI(MBB, MI, DL, ADDrr, DstR).addReg(DstR).add(Index);
     LLVM_DEBUG(NewMI->dump(););
     return NewMI;
   }
   // lea offset(%base,%index,scale), %dst =>
   // lea offset( ,%index,scale), %dst; add %base,%dst
-  MachineInstr *NewMI = BuildMI(*MFI, MI, DL, TII->get(LEAOpcode))
+  MachineInstr *NewMI = BuildMI(MBB, MI, DL, TII->get(LEAOpcode))
                             .add(Dst)
                             .addReg(0)
                             .add(Scale)
                             .add(Index)
                             .add(Offset)
                             .add(Segment);
   LLVM_DEBUG(NewMI->dump(););
 
-  NewMI = BuildMI(*MFI, MI, DL, ADDrr, DstR).addReg(DstR).add(Base);
+  NewMI = BuildMI(MBB, MI, DL, ADDrr, DstR).addReg(DstR).add(Base);
   LLVM_DEBUG(NewMI->dump(););
   return NewMI;
 }
-
-bool FixupLEAPass::processBasicBlock(MachineFunction &MF,
-                                     MachineFunction::iterator MFI,
-                                     bool IsSlowLEA, bool IsSlow3OpsLEA) {
-  for (MachineBasicBlock::iterator I = MFI->begin(); I != MFI->end(); ++I) {
-    if (OptIncDec)
-      if (fixupIncDec(I, MFI))
-        continue;
-
-    if (OptLEA) {
-      if (IsSlowLEA) {
-        processInstructionForSlowLEA(I, MFI);
-        continue;
-      }
-      
-      if (IsSlow3OpsLEA) {
-        if (auto *NewMI = processInstrForSlow3OpLEA(*I, MFI)) {
-          MFI->erase(I);
-          I = NewMI;
-        }
-        continue;
-      }
-
-      processInstruction(I, MFI);
-    }
-  }
-  return false;
-}

llvm/trunk/test/CodeGen/X86/lsr-static-addr.ll

 ; ATOM-NEXT:    xorl %eax, %eax
 ; ATOM-NEXT:    movsd {{.*#+}} xmm0 = mem[0],zero
 ; ATOM-NEXT:    .p2align 4, 0x90
 ; ATOM-NEXT:  .LBB0_2: # %for.body
 ; ATOM-NEXT:    # =>This Inner Loop Header: Depth=1
 ; ATOM-NEXT:    movsd {{.*#+}} xmm1 = mem[0],zero
 ; ATOM-NEXT:    mulsd %xmm0, %xmm1
 ; ATOM-NEXT:    movsd %xmm1, A(,%rax,8)
-; ATOM-NEXT:    incq %rax
+; ATOM-NEXT:    leaq 1(%rax), %rax
 ; ATOM-NEXT:    cmpq %rax, %rdi
 ; ATOM-NEXT:    jne .LBB0_2
 ; ATOM-NEXT:  .LBB0_3: # %for.end
 ; ATOM-NEXT:    nop
 ; ATOM-NEXT:    nop
 ; ATOM-NEXT:    nop
 ; ATOM-NEXT:    nop
 ; ATOM-NEXT:    retq