Added custom SELECT_CC lowering
Added special isel for ADDE,SUBE and new patterns to match SUBC,ADDC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52031 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 441f212..0e233c7 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -39,11 +39,12 @@
{
switch (Opcode)
{
- case MipsISD::JmpLink : return "MipsISD::JmpLink";
- case MipsISD::Hi : return "MipsISD::Hi";
- case MipsISD::Lo : return "MipsISD::Lo";
- case MipsISD::Ret : return "MipsISD::Ret";
- default : return NULL;
+ case MipsISD::JmpLink : return "MipsISD::JmpLink";
+ case MipsISD::Hi : return "MipsISD::Hi";
+ case MipsISD::Lo : return "MipsISD::Lo";
+ case MipsISD::Ret : return "MipsISD::Ret";
+ case MipsISD::SelectCC : return "MipsISD::SelectCC";
+ default : return NULL;
}
}
@@ -65,6 +66,7 @@
setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom);
setOperationAction(ISD::RET, MVT::Other, Custom);
setOperationAction(ISD::JumpTable, MVT::i32, Custom);
+ setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
// Load extented operations for i1 types must be promoted
setLoadXAction(ISD::EXTLOAD, MVT::i1, Promote);
@@ -75,7 +77,6 @@
setOperationAction(ISD::BR_JT, MVT::Other, Expand);
setOperationAction(ISD::BR_CC, MVT::Other, Expand);
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
- setOperationAction(ISD::SELECT_CC, MVT::i32, Expand);
setOperationAction(ISD::SELECT, MVT::i32, Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
@@ -124,10 +125,75 @@
case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG);
case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG);
case ISD::JumpTable: return LowerJumpTable(Op, DAG);
+ case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
}
return SDOperand();
}
+MachineBasicBlock *
+MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
+ MachineBasicBlock *BB)
+{
+ const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
+ switch (MI->getOpcode()) {
+ default: assert(false && "Unexpected instr type to insert");
+ case Mips::Select_CC: {
+ // To "insert" a SELECT_CC instruction, we actually have to insert the
+ // diamond control-flow pattern. The incoming instruction knows the
+ // destination vreg to set, the condition code register to branch on, the
+ // true/false values to select between, and a branch opcode to use.
+ const BasicBlock *LLVM_BB = BB->getBasicBlock();
+ ilist<MachineBasicBlock>::iterator It = BB;
+ ++It;
+
+ // thisMBB:
+ // ...
+ // TrueVal = ...
+ // setcc r1, r2, r3
+ // bNE r1, r0, copy1MBB
+ // fallthrough --> copy0MBB
+ MachineBasicBlock *thisMBB = BB;
+ MachineBasicBlock *copy0MBB = new MachineBasicBlock(LLVM_BB);
+ MachineBasicBlock *sinkMBB = new MachineBasicBlock(LLVM_BB);
+ BuildMI(BB, TII->get(Mips::BNE)).addReg(MI->getOperand(1).getReg())
+ .addReg(Mips::ZERO).addMBB(sinkMBB);
+ MachineFunction *F = BB->getParent();
+ F->getBasicBlockList().insert(It, copy0MBB);
+ F->getBasicBlockList().insert(It, sinkMBB);
+ // Update machine-CFG edges by first adding all successors of the current
+ // block to the new block which will contain the Phi node for the select.
+ for(MachineBasicBlock::succ_iterator i = BB->succ_begin(),
+ e = BB->succ_end(); i != e; ++i)
+ sinkMBB->addSuccessor(*i);
+ // Next, remove all successors of the current block, and add the true
+ // and fallthrough blocks as its successors.
+ while(!BB->succ_empty())
+ BB->removeSuccessor(BB->succ_begin());
+ BB->addSuccessor(copy0MBB);
+ BB->addSuccessor(sinkMBB);
+
+ // copy0MBB:
+ // %FalseValue = ...
+ // # fallthrough to sinkMBB
+ BB = copy0MBB;
+
+ // Update machine-CFG edges
+ BB->addSuccessor(sinkMBB);
+
+ // sinkMBB:
+ // %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
+ // ...
+ BB = sinkMBB;
+ BuildMI(BB, TII->get(Mips::PHI), MI->getOperand(0).getReg())
+ .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
+ .addReg(MI->getOperand(3).getReg()).addMBB(thisMBB);
+
+ delete MI; // The pseudo instruction is gone now.
+ return BB;
+ }
+ }
+}
+
//===----------------------------------------------------------------------===//
// Lower helper functions
//===----------------------------------------------------------------------===//
@@ -182,6 +248,23 @@
}
SDOperand MipsTargetLowering::
+LowerSELECT_CC(SDOperand Op, SelectionDAG &DAG)
+{
+ SDOperand LHS = Op.getOperand(0);
+ SDOperand RHS = Op.getOperand(1);
+ SDOperand True = Op.getOperand(2);
+ SDOperand False = Op.getOperand(3);
+ SDOperand CC = Op.getOperand(4);
+
+ const MVT::ValueType *VTs = DAG.getNodeValueTypes(MVT::i32);
+ SDOperand Ops[] = { LHS, RHS, CC };
+ SDOperand SetCCRes = DAG.getNode(ISD::SETCC, VTs, 1, Ops, 3);
+
+ return DAG.getNode(MipsISD::SelectCC, True.getValueType(),
+ SetCCRes, True, False);
+}
+
+SDOperand MipsTargetLowering::
LowerJumpTable(SDOperand Op, SelectionDAG &DAG)
{
SDOperand ResNode;