Simple branch instruction support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112923 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index 81a5140..4892eae 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -112,6 +112,7 @@
// Instruction selection routines.
virtual bool ARMSelectLoad(const Instruction *I);
virtual bool ARMSelectStore(const Instruction *I);
+ virtual bool ARMSelectBranch(const Instruction *I);
// Utility routines.
private:
@@ -619,6 +620,26 @@
return true;
}
+bool ARMFastISel::ARMSelectBranch(const Instruction *I) {
+ const BranchInst *BI = cast<BranchInst>(I);
+ MachineBasicBlock *TBB = FuncInfo.MBBMap[BI->getSuccessor(0)];
+ MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
+
+ // Simple branch support.
+ unsigned CondReg = getRegForValue(BI->getCondition());
+ if (CondReg == 0) return false;
+
+ unsigned CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
+ unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
+ AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
+ .addReg(CondReg).addReg(CondReg));
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
+ .addMBB(TBB).addImm(ARMCC::NE).addReg(ARM::CPSR);
+ FastEmitBranch(FBB, DL);
+ FuncInfo.MBB->addSuccessor(TBB);
+ return true;
+}
+
// TODO: SoftFP support.
bool ARMFastISel::TargetSelectInstruction(const Instruction *I) {
// No Thumb-1 for now.
@@ -629,6 +650,8 @@
return ARMSelectLoad(I);
case Instruction::Store:
return ARMSelectStore(I);
+ case Instruction::Br:
+ return ARMSelectBranch(I);
default: break;
}
return false;