From 90b25eaef278779c7b582217ca25f0293d8aa65b Mon Sep 17 00:00:00 2001
From: Tim Northover <tnorthover@apple.com>
Date: Tue, 11 Mar 2014 13:19:55 +0000
Subject: [PATCH] ARM: simplify EmitAtomicBinary64

ATOMIC_STORE operations always get here as a lowered ATOMIC_SWAP, so there's no
need for any code to handle them specially.

There should be no functionality change so no tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203567 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/ARM/ARMISelDAGToDAG.cpp |  6 -----
 lib/Target/ARM/ARMISelLowering.cpp | 42 ++++++++++++++----------------
 lib/Target/ARM/ARMInstrInfo.td     |  5 ----
 3 files changed, 19 insertions(+), 34 deletions(-)

diff --git a/lib/Target/ARM/ARMISelDAGToDAG.cpp b/lib/Target/ARM/ARMISelDAGToDAG.cpp
index 034cca274e8..72008ecc33c 100644
--- a/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -3323,12 +3323,6 @@ SDNode *ARMDAGToDAGISel::Select(SDNode *N) {
     else
       break;
 
-  case ISD::ATOMIC_STORE:
-    if (cast<AtomicSDNode>(N)->getMemoryVT() == MVT::i64)
-      return SelectAtomic(N, 0, 0, 0, ARM::ATOMIC_STORE_I64);
-    else
-      break;
-
   case ISD::ATOMIC_LOAD_ADD:
     return SelectAtomic(N,
                         ARM::ATOMIC_LOAD_ADD_I8,
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index aa7ca7f91ff..74f0ac539ed 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -6517,15 +6517,13 @@ ARMTargetLowering::EmitAtomicBinary64(MachineInstr *MI, MachineBasicBlock *BB,
   MachineFunction::iterator It = BB;
   ++It;
 
-  bool isStore = (MI->getOpcode() == ARM::ATOMIC_STORE_I64);
-  unsigned offset = (isStore ? -2 : 0);
   unsigned destlo = MI->getOperand(0).getReg();
   unsigned desthi = MI->getOperand(1).getReg();
-  unsigned ptr = MI->getOperand(offset+2).getReg();
-  unsigned vallo = MI->getOperand(offset+3).getReg();
-  unsigned valhi = MI->getOperand(offset+4).getReg();
-  unsigned OrdIdx = offset + (IsCmpxchg ? 7 : 5);
-  AtomicOrdering Ord = static_cast<AtomicOrdering>(MI->getOperand(OrdIdx).getImm());
+  unsigned ptr = MI->getOperand(2).getReg();
+  unsigned vallo = MI->getOperand(3).getReg();
+  unsigned valhi = MI->getOperand(4).getReg();
+  AtomicOrdering Ord =
+      static_cast<AtomicOrdering>(MI->getOperand(IsCmpxchg ? 7 : 5).getImm());
   DebugLoc dl = MI->getDebugLoc();
   bool isThumb2 = Subtarget->isThumb2();
 
@@ -6579,23 +6577,22 @@ ARMTargetLowering::EmitAtomicBinary64(MachineInstr *MI, MachineBasicBlock *BB,
   //   fallthrough --> exitMBB
   BB = loopMBB;
 
-  if (!isStore) {
-    // Load
-    if (isThumb2) {
-      AddDefaultPred(BuildMI(BB, dl, TII->get(ldrOpc))
-                     .addReg(destlo, RegState::Define)
-                     .addReg(desthi, RegState::Define)
-                     .addReg(ptr));
-    } else {
-      unsigned GPRPair0 = MRI.createVirtualRegister(&ARM::GPRPairRegClass);
-      AddDefaultPred(BuildMI(BB, dl, TII->get(ldrOpc))
-                     .addReg(GPRPair0, RegState::Define).addReg(ptr));
-      // Copy r2/r3 into dest.  (This copy will normally be coalesced.)
-      BuildMI(BB, dl, TII->get(TargetOpcode::COPY), destlo)
+  // Load
+  if (isThumb2) {
+    AddDefaultPred(BuildMI(BB, dl, TII->get(ldrOpc))
+                       .addReg(destlo, RegState::Define)
+                       .addReg(desthi, RegState::Define)
+                       .addReg(ptr));
+  } else {
+    unsigned GPRPair0 = MRI.createVirtualRegister(&ARM::GPRPairRegClass);
+    AddDefaultPred(BuildMI(BB, dl, TII->get(ldrOpc))
+                       .addReg(GPRPair0, RegState::Define)
+                       .addReg(ptr));
+    // Copy r2/r3 into dest.  (This copy will normally be coalesced.)
+    BuildMI(BB, dl, TII->get(TargetOpcode::COPY), destlo)
         .addReg(GPRPair0, 0, ARM::gsub_0);
-      BuildMI(BB, dl, TII->get(TargetOpcode::COPY), desthi)
+    BuildMI(BB, dl, TII->get(TargetOpcode::COPY), desthi)
         .addReg(GPRPair0, 0, ARM::gsub_1);
-    }
   }
 
   unsigned StoreLo, StoreHi;
@@ -7761,7 +7758,6 @@ ARMTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
   case ARM::ATOMIC_LOAD_AND_I64:
     return EmitAtomicBinary64(MI, BB, isThumb2 ? ARM::t2ANDrr : ARM::ANDrr,
                               isThumb2 ? ARM::t2ANDrr : ARM::ANDrr);
-  case ARM::ATOMIC_STORE_I64:
   case ARM::ATOMIC_SWAP_I64:
     return EmitAtomicBinary64(MI, BB, 0, 0, false);
   case ARM::ATOMIC_CMP_SWAP_I64:
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 2bfde5fbe48..d4976594d4f 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -4538,11 +4538,6 @@ let usesCustomInserter = 1, Defs = [CPSR] in {
       (outs GPR:$dst1, GPR:$dst2),
       (ins GPR:$addr, i32imm:$ordering),
       NoItinerary, []>;
-  let mayStore = 1 in
-    def ATOMIC_STORE_I64 : PseudoInst<
-      (outs GPR:$dst1, GPR:$dst2),
-      (ins GPR:$addr, GPR:$src1, GPR:$src2, i32imm:$ordering),
-      NoItinerary, []>;
 }
 
 let usesCustomInserter = 1 in {
-- 
2.34.1