Index: llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
===================================================================
--- llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ llvm/trunk/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -118,6 +118,7 @@
     };
     BumpPtrAllocator Allocator;
     SmallVector<const MergeCandidate*,4> Candidates;
+    SmallVector<MachineInstr*,4> MergeBaseCandidates;
 
     void moveLiveRegsBefore(const MachineBasicBlock &MBB,
                             MachineBasicBlock::const_iterator Before);
@@ -140,6 +141,7 @@
                              MachineBasicBlock::iterator &MBBI);
     bool MergeBaseUpdateLoadStore(MachineInstr *MI);
     bool MergeBaseUpdateLSMultiple(MachineInstr *MI);
+    bool MergeBaseUpdateLSDouble(MachineInstr &MI) const;
     bool LoadStoreMultipleOpti(MachineBasicBlock &MBB);
     bool MergeReturnIntoLDM(MachineBasicBlock &MBB);
   };
@@ -1010,76 +1012,6 @@
   } while (SIndex < EIndex);
 }
 
-static bool isMatchingDecrement(MachineInstr *MI, unsigned Base,
-                                unsigned Bytes, unsigned Limit,
-                                ARMCC::CondCodes Pred, unsigned PredReg) {
-  unsigned MyPredReg = 0;
-  if (!MI)
-    return false;
-
-  bool CheckCPSRDef = false;
-  switch (MI->getOpcode()) {
-  default: return false;
-  case ARM::tSUBi8:
-  case ARM::t2SUBri:
-  case ARM::SUBri:
-    CheckCPSRDef = true;
-    break;
-  case ARM::tSUBspi:
-    break;
-  }
-
-  // Make sure the offset fits in 8 bits.
-  if (Bytes == 0 || (Limit && Bytes >= Limit))
-    return false;
-
-  unsigned Scale = (MI->getOpcode() == ARM::tSUBspi ||
-                    MI->getOpcode() == ARM::tSUBi8) ? 4 : 1; // FIXME
-  if (!(MI->getOperand(0).getReg() == Base &&
-        MI->getOperand(1).getReg() == Base &&
-        (MI->getOperand(2).getImm() * Scale) == Bytes &&
-        getInstrPredicate(MI, MyPredReg) == Pred &&
-        MyPredReg == PredReg))
-    return false;
-
-  return CheckCPSRDef ? !definesCPSR(MI) : true;
-}
-
-static bool isMatchingIncrement(MachineInstr *MI, unsigned Base,
-                                unsigned Bytes, unsigned Limit,
-                                ARMCC::CondCodes Pred, unsigned PredReg) {
-  unsigned MyPredReg = 0;
-  if (!MI)
-    return false;
-
-  bool CheckCPSRDef = false;
-  switch (MI->getOpcode()) {
-  default: return false;
-  case ARM::tADDi8:
-  case ARM::t2ADDri:
-  case ARM::ADDri:
-    CheckCPSRDef = true;
-    break;
-  case ARM::tADDspi:
-    break;
-  }
-
-  if (Bytes == 0 || (Limit && Bytes >= Limit))
-    // Make sure the offset fits in 8 bits.
-    return false;
-
-  unsigned Scale = (MI->getOpcode() == ARM::tADDspi ||
-                    MI->getOpcode() == ARM::tADDi8) ? 4 : 1; // FIXME
-  if (!(MI->getOperand(0).getReg() == Base &&
-        MI->getOperand(1).getReg() == Base &&
-        (MI->getOperand(2).getImm() * Scale) == Bytes &&
-        getInstrPredicate(MI, MyPredReg) == Pred &&
-        MyPredReg == PredReg))
-    return false;
-
-  return CheckCPSRDef ? !definesCPSR(MI) : true;
-}
-
 static unsigned getUpdatingLSMultipleOpcode(unsigned Opc,
                                             ARM_AM::AMSubMode Mode) {
   switch (Opc) {
@@ -1147,6 +1079,75 @@
   }
 }
 
+/// Check if the given instruction increments or decrements a register and
+/// return the amount it is incremented/decremented. Returns 0 if the CPSR flags
+/// generated by the instruction are possibly read as well.
+static int isIncrementOrDecrement(const MachineInstr &MI, unsigned Reg,
+                                  ARMCC::CondCodes Pred, unsigned PredReg) {
+  bool CheckCPSRDef;
+  int Scale;
+  switch (MI.getOpcode()) {
+  case ARM::tADDi8:  Scale =  4; CheckCPSRDef = true; break;
+  case ARM::tSUBi8:  Scale = -4; CheckCPSRDef = true; break;
+  case ARM::t2SUBri:
+  case ARM::SUBri:   Scale = -1; CheckCPSRDef = true; break;
+  case ARM::t2ADDri:
+  case ARM::ADDri:   Scale =  1; CheckCPSRDef = true; break;
+  case ARM::tADDspi: Scale =  4; CheckCPSRDef = false; break;
+  case ARM::tSUBspi: Scale = -4; CheckCPSRDef = false; break;
+  default: return 0;
+  }
+
+  unsigned MIPredReg;
+  if (MI.getOperand(0).getReg() != Reg ||
+      MI.getOperand(1).getReg() != Reg ||
+      getInstrPredicate(&MI, MIPredReg) != Pred ||
+      MIPredReg != PredReg)
+    return 0;
+
+  if (CheckCPSRDef && definesCPSR(&MI))
+    return 0;
+  return MI.getOperand(2).getImm() * Scale;
+}
+
+/// Searches for an increment or decrement of \p Reg before \p MBBI.
+static MachineBasicBlock::iterator
+findIncDecBefore(MachineBasicBlock::iterator MBBI, unsigned Reg,
+                 ARMCC::CondCodes Pred, unsigned PredReg, int &Offset) {
+  Offset = 0;
+  MachineBasicBlock &MBB = *MBBI->getParent();
+  MachineBasicBlock::iterator BeginMBBI = MBB.begin();
+  MachineBasicBlock::iterator EndMBBI = MBB.end();
+  if (MBBI == BeginMBBI)
+    return EndMBBI;
+
+  // Skip debug values.
+  MachineBasicBlock::iterator PrevMBBI = std::prev(MBBI);
+  while (PrevMBBI->isDebugValue() && PrevMBBI != BeginMBBI)
+    --PrevMBBI;
+
+  Offset = isIncrementOrDecrement(*PrevMBBI, Reg, Pred, PredReg);
+  return Offset == 0 ? EndMBBI : PrevMBBI;
+}
+
+/// Searches for a increment or decrement of \p Reg after \p MBBI.
+static MachineBasicBlock::iterator
+findIncDecAfter(MachineBasicBlock::iterator MBBI, unsigned Reg,
+                ARMCC::CondCodes Pred, unsigned PredReg, int &Offset) {
+  Offset = 0;
+  MachineBasicBlock &MBB = *MBBI->getParent();
+  MachineBasicBlock::iterator EndMBBI = MBB.end();
+  MachineBasicBlock::iterator NextMBBI = std::next(MBBI);
+  // Skip debug values.
+  while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
+    ++NextMBBI;
+  if (NextMBBI == EndMBBI)
+    return EndMBBI;
+
+  Offset = isIncrementOrDecrement(*NextMBBI, Reg, Pred, PredReg);
+  return Offset == 0 ? EndMBBI : NextMBBI;
+}
+
 /// Fold proceeding/trailing inc/dec of base register into the
 /// LDM/STM/VLDM{D|S}/VSTM{D|S} op when possible:
 ///
@@ -1166,7 +1167,6 @@
   const MachineOperand &BaseOP = MI->getOperand(0);
   unsigned Base = BaseOP.getReg();
   bool BaseKill = BaseOP.isKill();
-  unsigned Bytes = getLSMultipleTransferSize(MI);
   unsigned PredReg = 0;
   ARMCC::CondCodes Pred = getInstrPredicate(MI, PredReg);
   unsigned Opcode = MI->getOpcode();
@@ -1178,49 +1178,24 @@
     if (MI->getOperand(i).getReg() == Base)
       return false;
 
-  bool DoMerge = false;
-  ARM_AM::AMSubMode Mode = getLoadStoreMultipleSubMode(Opcode);
-
-  // Try merging with the previous instruction.
+  int Bytes = getLSMultipleTransferSize(MI);
   MachineBasicBlock &MBB = *MI->getParent();
-  MachineBasicBlock::iterator BeginMBBI = MBB.begin();
   MachineBasicBlock::iterator MBBI(MI);
-  if (MBBI != BeginMBBI) {
-    MachineBasicBlock::iterator PrevMBBI = std::prev(MBBI);
-    while (PrevMBBI != BeginMBBI && PrevMBBI->isDebugValue())
-      --PrevMBBI;
-    if (Mode == ARM_AM::ia &&
-        isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
-      Mode = ARM_AM::db;
-      DoMerge = true;
-    } else if (Mode == ARM_AM::ib &&
-               isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
-      Mode = ARM_AM::da;
-      DoMerge = true;
-    }
-    if (DoMerge)
-      MBB.erase(PrevMBBI);
-  }
-
-  // Try merging with the next instruction.
-  MachineBasicBlock::iterator EndMBBI = MBB.end();
-  if (!DoMerge && MBBI != EndMBBI) {
-    MachineBasicBlock::iterator NextMBBI = std::next(MBBI);
-    while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
-      ++NextMBBI;
-    if ((Mode == ARM_AM::ia || Mode == ARM_AM::ib) &&
-        isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
-      DoMerge = true;
-    } else if ((Mode == ARM_AM::da || Mode == ARM_AM::db) &&
-               isMatchingDecrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
-      DoMerge = true;
-    }
-    if (DoMerge)
-      MBB.erase(NextMBBI);
+  int Offset;
+  MachineBasicBlock::iterator MergeInstr
+    = findIncDecBefore(MBBI, Base, Pred, PredReg, Offset);
+  ARM_AM::AMSubMode Mode = getLoadStoreMultipleSubMode(Opcode);
+  if (Mode == ARM_AM::ia && Offset == -Bytes) {
+    Mode = ARM_AM::db;
+  } else if (Mode == ARM_AM::ib && Offset == -Bytes) {
+    Mode = ARM_AM::da;
+  } else {
+    MergeInstr = findIncDecAfter(MBBI, Base, Pred, PredReg, Offset);
+    if (((Mode != ARM_AM::ia && Mode != ARM_AM::ib) || Offset != Bytes) &&
+        ((Mode != ARM_AM::da && Mode != ARM_AM::db) || Offset != -Bytes))
+      return false;
   }
-
-  if (!DoMerge)
-    return false;
+  MBB.erase(MergeInstr);
 
   unsigned NewOpc = getUpdatingLSMultipleOpcode(Opcode, Mode);
   MachineInstrBuilder MIB = BuildMI(MBB, MBBI, DL, TII->get(NewOpc))
@@ -1298,7 +1273,6 @@
 
   unsigned Base = getLoadStoreBaseOp(*MI).getReg();
   bool BaseKill = getLoadStoreBaseOp(*MI).isKill();
-  unsigned Bytes = getLSMultipleTransferSize(MI);
   unsigned Opcode = MI->getOpcode();
   DebugLoc DL = MI->getDebugLoc();
   bool isAM5 = (Opcode == ARM::VLDRD || Opcode == ARM::VLDRS ||
@@ -1310,7 +1284,6 @@
   if (isAM5 && ARM_AM::getAM5Offset(MI->getOperand(2).getImm()) != 0)
     return false;
 
-  bool isLd = isLoadSingle(Opcode);
   // Can't do the merge if the destination register is the same as the would-be
   // writeback register.
   if (MI->getOperand(0).getReg() == Base)
@@ -1318,55 +1291,31 @@
 
   unsigned PredReg = 0;
   ARMCC::CondCodes Pred = getInstrPredicate(MI, PredReg);
-  bool DoMerge = false;
-  ARM_AM::AddrOpc AddSub = ARM_AM::add;
-  unsigned NewOpc = 0;
-  // AM2 - 12 bits, thumb2 - 8 bits.
-  unsigned Limit = isAM5 ? 0 : (isAM2 ? 0x1000 : 0x100);
-
-  // Try merging with the previous instruction.
+  int Bytes = getLSMultipleTransferSize(MI);
   MachineBasicBlock &MBB = *MI->getParent();
-  MachineBasicBlock::iterator BeginMBBI = MBB.begin();
   MachineBasicBlock::iterator MBBI(MI);
-  if (MBBI != BeginMBBI) {
-    MachineBasicBlock::iterator PrevMBBI = std::prev(MBBI);
-    while (PrevMBBI != BeginMBBI && PrevMBBI->isDebugValue())
-      --PrevMBBI;
-    if (isMatchingDecrement(PrevMBBI, Base, Bytes, Limit, Pred, PredReg)) {
-      DoMerge = true;
-      AddSub = ARM_AM::sub;
-    } else if (!isAM5 &&
-               isMatchingIncrement(PrevMBBI, Base, Bytes, Limit,Pred,PredReg)) {
-      DoMerge = true;
-    }
-    if (DoMerge) {
-      NewOpc = getPreIndexedLoadStoreOpcode(Opcode, AddSub);
-      MBB.erase(PrevMBBI);
-    }
-  }
-
-  // Try merging with the next instruction.
-  MachineBasicBlock::iterator EndMBBI = MBB.end();
-  if (!DoMerge && MBBI != EndMBBI) {
-    MachineBasicBlock::iterator NextMBBI = std::next(MBBI);
-    while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
-      ++NextMBBI;
-    if (!isAM5 &&
-        isMatchingDecrement(NextMBBI, Base, Bytes, Limit, Pred, PredReg)) {
-      DoMerge = true;
-      AddSub = ARM_AM::sub;
-    } else if (isMatchingIncrement(NextMBBI, Base, Bytes, Limit,Pred,PredReg)) {
-      DoMerge = true;
-    }
-    if (DoMerge) {
-      NewOpc = getPostIndexedLoadStoreOpcode(Opcode, AddSub);
-      MBB.erase(NextMBBI);
-    }
+  int Offset;
+  MachineBasicBlock::iterator MergeInstr
+    = findIncDecBefore(MBBI, Base, Pred, PredReg, Offset);
+  unsigned NewOpc;
+  if (!isAM5 && Offset == Bytes) {
+    NewOpc = getPreIndexedLoadStoreOpcode(Opcode, ARM_AM::add);
+  } else if (Offset == -Bytes) {
+    NewOpc = getPreIndexedLoadStoreOpcode(Opcode, ARM_AM::sub);
+  } else {
+    MergeInstr = findIncDecAfter(MBBI, Base, Pred, PredReg, Offset);
+    if (Offset == Bytes) {
+      NewOpc = getPostIndexedLoadStoreOpcode(Opcode, ARM_AM::add);
+    } else if (!isAM5 && Offset == -Bytes) {
+      NewOpc = getPostIndexedLoadStoreOpcode(Opcode, ARM_AM::sub);
+    } else
+      return false;
   }
+  MBB.erase(MergeInstr);
 
-  if (!DoMerge)
-    return false;
+  ARM_AM::AddrOpc AddSub = Offset < 0 ? ARM_AM::sub : ARM_AM::add;
 
+  bool isLd = isLoadSingle(Opcode);
   if (isAM5) {
     // VLDM[SD]_UPD, VSTM[SD]_UPD
     // (There are no base-updating versions of VLDR/VSTR instructions, but the
@@ -1383,18 +1332,16 @@
     if (isAM2) {
       // LDR_PRE, LDR_POST
       if (NewOpc == ARM::LDR_PRE_IMM || NewOpc == ARM::LDRB_PRE_IMM) {
-        int Offset = AddSub == ARM_AM::sub ? -Bytes : Bytes;
         BuildMI(MBB, MBBI, DL, TII->get(NewOpc), MI->getOperand(0).getReg())
           .addReg(Base, RegState::Define)
           .addReg(Base).addImm(Offset).addImm(Pred).addReg(PredReg);
       } else {
-        int Offset = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
+        int Imm = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
         BuildMI(MBB, MBBI, DL, TII->get(NewOpc), MI->getOperand(0).getReg())
           .addReg(Base, RegState::Define)
-          .addReg(Base).addReg(0).addImm(Offset).addImm(Pred).addReg(PredReg);
+          .addReg(Base).addReg(0).addImm(Imm).addImm(Pred).addReg(PredReg);
       }
     } else {
-      int Offset = AddSub == ARM_AM::sub ? -Bytes : Bytes;
       // t2LDR_PRE, t2LDR_POST
       BuildMI(MBB, MBBI, DL, TII->get(NewOpc), MI->getOperand(0).getReg())
         .addReg(Base, RegState::Define)
@@ -1406,13 +1353,12 @@
     // the vestigal zero-reg offset register. When that's fixed, this clause
     // can be removed entirely.
     if (isAM2 && NewOpc == ARM::STR_POST_IMM) {
-      int Offset = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
+      int Imm = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
       // STR_PRE, STR_POST
       BuildMI(MBB, MBBI, DL, TII->get(NewOpc), Base)
         .addReg(MO.getReg(), getKillRegState(MO.isKill()))
-        .addReg(Base).addReg(0).addImm(Offset).addImm(Pred).addReg(PredReg);
+        .addReg(Base).addReg(0).addImm(Imm).addImm(Pred).addReg(PredReg);
     } else {
-      int Offset = AddSub == ARM_AM::sub ? -Bytes : Bytes;
       // t2STR_PRE, t2STR_POST
       BuildMI(MBB, MBBI, DL, TII->get(NewOpc), Base)
         .addReg(MO.getReg(), getKillRegState(MO.isKill()))
@@ -1424,6 +1370,66 @@
   return true;
 }
 
+bool ARMLoadStoreOpt::MergeBaseUpdateLSDouble(MachineInstr &MI) const {
+  unsigned Opcode = MI.getOpcode();
+  assert((Opcode == ARM::t2LDRDi8 || Opcode == ARM::t2STRDi8) &&
+         "Must have t2STRDi8 or t2LDRDi8");
+  if (MI.getOperand(3).getImm() != 0)
+    return false;
+
+  // Behaviour for writeback is undefined if base register is the same as one
+  // of the others.
+  const MachineOperand &BaseOp = MI.getOperand(2);
+  unsigned Base = BaseOp.getReg();
+  const MachineOperand &Reg0Op = MI.getOperand(0);
+  const MachineOperand &Reg1Op = MI.getOperand(1);
+  if (Reg0Op.getReg() == Base || Reg1Op.getReg() == Base)
+    return false;
+
+  unsigned PredReg;
+  ARMCC::CondCodes Pred = getInstrPredicate(&MI, PredReg);
+  MachineBasicBlock::iterator MBBI(MI);
+  MachineBasicBlock &MBB = *MI.getParent();
+  int Offset;
+  MachineBasicBlock::iterator MergeInstr = findIncDecBefore(MBBI, Base, Pred,
+                                                            PredReg, Offset);
+  unsigned NewOpc;
+  if (Offset == 8 || Offset == -8) {
+    NewOpc = Opcode == ARM::t2LDRDi8 ? ARM::t2LDRD_PRE : ARM::t2STRD_PRE;
+  } else {
+    MergeInstr = findIncDecAfter(MBBI, Base, Pred, PredReg, Offset);
+    if (Offset == 8 || Offset == -8) {
+      NewOpc = Opcode == ARM::t2LDRDi8 ? ARM::t2LDRD_POST : ARM::t2STRD_POST;
+    } else
+      return false;
+  }
+  MBB.erase(MergeInstr);
+
+  DebugLoc DL = MI.getDebugLoc();
+  MachineInstrBuilder MIB = BuildMI(MBB, MBBI, DL, TII->get(NewOpc));
+  if (NewOpc == ARM::t2LDRD_PRE || NewOpc == ARM::t2LDRD_POST) {
+    MIB.addOperand(Reg0Op).addOperand(Reg1Op)
+       .addReg(BaseOp.getReg(), RegState::Define);
+  } else {
+    assert(NewOpc == ARM::t2STRD_PRE || NewOpc == ARM::t2STRD_POST);
+    MIB.addReg(BaseOp.getReg(), RegState::Define)
+       .addOperand(Reg0Op).addOperand(Reg1Op);
+  }
+  MIB.addReg(BaseOp.getReg(), RegState::Kill)
+     .addImm(Offset).addImm(Pred).addReg(PredReg);
+  assert(TII->get(Opcode).getNumOperands() == 6 &&
+         TII->get(NewOpc).getNumOperands() == 7 &&
+         "Unexpected number of operands in Opcode specification.");
+
+  // Transfer implicit operands.
+  for (const MachineOperand &MO : MI.implicit_operands())
+    MIB.addOperand(MO);
+  MIB->setMemRefs(MI.memoperands_begin(), MI.memoperands_end());
+
+  MBB.erase(MBBI);
+  return true;
+}
+
 /// Returns true if instruction is a memory operation that this pass is capable
 /// of operating on.
 static bool isMemoryOp(const MachineInstr *MI) {
@@ -1633,6 +1639,7 @@
   unsigned CurrPredReg = 0;
   unsigned Position = 0;
   assert(Candidates.size() == 0);
+  assert(MergeBaseCandidates.size() == 0);
   LiveRegsValid = false;
 
   for (MachineBasicBlock::iterator I = MBB.end(), MBBI; I != MBB.begin();
@@ -1714,8 +1721,15 @@
       MBBI = I;
       --Position;
       // Fallthrough to look into existing chain.
-    } else if (MBBI->isDebugValue())
+    } else if (MBBI->isDebugValue()) {
       continue;
+    } else if (MBBI->getOpcode() == ARM::t2LDRDi8 ||
+               MBBI->getOpcode() == ARM::t2STRDi8) {
+      // ARMPreAllocLoadStoreOpt has already formed some LDRD/STRD instructions
+      // remember them because we may still be able to merge add/sub into them.
+      MergeBaseCandidates.push_back(MBBI);
+    }
+
 
     // If we are here then the chain is broken; Extract candidates for a merge.
     if (MemOps.size() > 0) {
@@ -1748,7 +1762,9 @@
       if (Merged) {
         Changed = true;
         unsigned Opcode = Merged->getOpcode();
-        if (Opcode != ARM::t2STRDi8 && Opcode != ARM::t2LDRDi8)
+        if (Opcode == ARM::t2STRDi8 || Opcode == ARM::t2LDRDi8)
+          MergeBaseUpdateLSDouble(*Merged);
+        else
           MergeBaseUpdateLSMultiple(Merged);
       } else {
         for (MachineInstr *MI : Candidate->Instrs) {
@@ -1763,6 +1779,10 @@
     }
   }
   Candidates.clear();
+  // Try to fold add/sub into the LDRD/STRD formed by ARMPreAllocLoadStoreOpt.
+  for (MachineInstr *MI : MergeBaseCandidates)
+    MergeBaseUpdateLSDouble(*MI);
+  MergeBaseCandidates.clear();
 
   return Changed;
 }
Index: llvm/trunk/test/CodeGen/ARM/ldrd.ll
===================================================================
--- llvm/trunk/test/CodeGen/ARM/ldrd.ll
+++ llvm/trunk/test/CodeGen/ARM/ldrd.ll
@@ -112,10 +112,10 @@
 }
 
 ; CHECK-LABEL: strd_spill_ldrd_reload:
-; A8: strd r1, r0, [sp]
-; M3: strd r1, r0, [sp]
-; BASIC: strd r1, r0, [sp]
-; GREEDY: strd r0, r1, [sp]
+; A8: strd r1, r0, [sp, #-8]!
+; M3: strd r1, r0, [sp, #-8]!
+; BASIC: strd r1, r0, [sp, #-8]!
+; GREEDY: strd r0, r1, [sp, #-8]!
 ; CHECK: @ InlineAsm Start
 ; CHECK: @ InlineAsm End
 ; A8: ldrd r2, r1, [sp]
@@ -131,5 +131,53 @@
   ret void
 }
 
+declare void @extfunc2(i32*, i32, i32)
+
+; CHECK-LABEL: ldrd_postupdate_dec:
+; CHECK: ldrd r1, r2, [r0], #-8
+; CHECK-NEXT: bl{{x?}} _extfunc
+define void @ldrd_postupdate_dec(i32* %p0) {
+  %p0.1 = getelementptr i32, i32* %p0, i32 1
+  %v0 = load i32, i32* %p0
+  %v1 = load i32, i32* %p0.1
+  %p1 = getelementptr i32, i32* %p0, i32 -2
+  call void @extfunc2(i32* %p1, i32 %v0, i32 %v1)
+  ret void
+}
+
+; CHECK-LABEL: ldrd_postupdate_inc:
+; CHECK: ldrd r1, r2, [r0], #8
+; CHECK-NEXT: bl{{x?}} _extfunc
+define void @ldrd_postupdate_inc(i32* %p0) {
+  %p0.1 = getelementptr i32, i32* %p0, i32 1
+  %v0 = load i32, i32* %p0
+  %v1 = load i32, i32* %p0.1
+  %p1 = getelementptr i32, i32* %p0, i32 2
+  call void @extfunc2(i32* %p1, i32 %v0, i32 %v1)
+  ret void
+}
+
+; CHECK-LABEL: strd_postupdate_dec:
+; CHECK: strd r1, r2, [r0], #-8
+; CHECK-NEXT: bx lr
+define i32* @strd_postupdate_dec(i32* %p0, i32 %v0, i32 %v1) {
+  %p0.1 = getelementptr i32, i32* %p0, i32 1
+  store i32 %v0, i32* %p0
+  store i32 %v1, i32* %p0.1
+  %p1 = getelementptr i32, i32* %p0, i32 -2
+  ret i32* %p1
+}
+
+; CHECK-LABEL: strd_postupdate_inc:
+; CHECK: strd r1, r2, [r0], #8
+; CHECK-NEXT: bx lr
+define i32* @strd_postupdate_inc(i32* %p0, i32 %v0, i32 %v1) {
+  %p0.1 = getelementptr i32, i32* %p0, i32 1
+  store i32 %v0, i32* %p0
+  store i32 %v1, i32* %p0.1
+  %p1 = getelementptr i32, i32* %p0, i32 2
+  ret i32* %p1
+}
+
 declare void @llvm.lifetime.start(i64, i8* nocapture) nounwind
 declare void @llvm.lifetime.end(i64, i8* nocapture) nounwind