Convert ADCS and SBCS instructions into pseudos that are expanded to the ADC/ABC with the appropriate S-bit input value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128892 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 47 insertions, 0 deletions

diff --git a/lib/Target/ARM/ARMExpandPseudoInsts.cpp b/lib/Target/ARM/ARMExpandPseudoInsts.cpp
index a14c9526fc..547b27d486 100644
--- a/lib/Target/ARM/ARMExpandPseudoInsts.cpp
+++ b/lib/Target/ARM/ARMExpandPseudoInsts.cpp
@@ -55,6 +55,7 @@ namespace {
     void ExpandVLD(MachineBasicBlock::iterator &MBBI);
     void ExpandVST(MachineBasicBlock::iterator &MBBI);
     void ExpandLaneOp(MachineBasicBlock::iterator &MBBI);
+    void ExpandSBitOp(MachineBasicBlock::iterator &MBBI);
     void ExpandVTBL(MachineBasicBlock::iterator &MBBI,
                     unsigned Opc, bool IsExt, unsigned NumRegs);
     void ExpandMOV32BitImm(MachineBasicBlock &MBB,
@@ -629,6 +630,43 @@ void ARMExpandPseudo::ExpandVTBL(MachineBasicBlock::iterator &MBBI,
   MI.eraseFromParent();
 }
 
+void ARMExpandPseudo::ExpandSBitOp(MachineBasicBlock::iterator &MBBI) {
+  MachineInstr &MI = *MBBI;
+  MachineBasicBlock &MBB = *MI.getParent();
+  unsigned OldOpc = MI.getOpcode();
+  unsigned Opc = 0;
+  switch (OldOpc) {
+    case ARM::ADCSSrr:
+      Opc = ARM::ADCrr;
+      break;
+    case ARM::ADCSSri:
+      Opc = ARM::ADCri;
+      break;
+    case ARM::ADCSSrs:
+      Opc = ARM::ADCrs;
+      break;
+    case ARM::SBCSSrr:
+      Opc = ARM::SBCrr;
+      break;
+    case ARM::SBCSSri:
+      Opc = ARM::SBCri;
+      break;
+    case ARM::SBCSSrs:
+      Opc = ARM::SBCrs;
+      break;
+    default:
+      llvm_unreachable("Unknown opcode?");
+  }
+
+  MachineInstrBuilder MIB = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(Opc));
+  MIB.addOperand(MachineOperand::CreateImm(0)); // Predicate
+  MIB.addOperand(MachineOperand::CreateImm(0)); // S bit
+  for (unsigned i = 0; i < MI.getNumOperands(); ++i)
+    MIB.addOperand(MI.getOperand(i));
+  TransferImpOps(MI, MIB, MIB);
+  MI.eraseFromParent();
+}
+
 void ARMExpandPseudo::ExpandMOV32BitImm(MachineBasicBlock &MBB,
                                         MachineBasicBlock::iterator &MBBI) {
   MachineInstr &MI = *MBBI;
@@ -941,6 +979,15 @@ bool ARMExpandPseudo::ExpandMI(MachineBasicBlock &MBB,
       ExpandMOV32BitImm(MBB, MBBI);
       return true;
 
+    case ARM::ADCSSri:
+    case ARM::ADCSSrr:
+    case ARM::ADCSSrs:
+    case ARM::SBCSSri:
+    case ARM::SBCSSrr:
+    case ARM::SBCSSrs:
+      ExpandSBitOp(MBBI);
+      return true;
+
     case ARM::VMOVQQ: {
       unsigned DstReg = MI.getOperand(0).getReg();
       bool DstIsDead = MI.getOperand(0).isDead();