[fast-isel] ARMEmitCmp generates FMSTAT, which transfers the floating-point
condition flags to CPSR. This allows us to simplify SelectCmp.
Patch by Zonr Chang <zonr.xchg@gmail.com>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152243 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index 365f1b6..71de52f 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -1475,7 +1475,6 @@
bool ARMFastISel::SelectCmp(const Instruction *I) {
const CmpInst *CI = cast<CmpInst>(I);
- Type *Ty = CI->getOperand(0)->getType();
// Get the compare predicate.
ARMCC::CondCodes ARMPred = getComparePred(CI->getPredicate());
@@ -1495,11 +1494,10 @@
unsigned DestReg = createResultReg(RC);
Constant *Zero = ConstantInt::get(Type::getInt32Ty(*Context), 0);
unsigned ZeroReg = TargetMaterializeConstant(Zero);
- bool isFloat = (Ty->isFloatTy() || Ty->isDoubleTy());
- unsigned CondReg = isFloat ? ARM::FPSCR_NZCV : ARM::CPSR;
+ // ARMEmitCmp emits a FMSTAT when necessary, so it's always safe to use CPSR.
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(MovCCOpc), DestReg)
.addReg(ZeroReg).addImm(1)
- .addImm(ARMPred).addReg(CondReg);
+ .addImm(ARMPred).addReg(ARM::CPSR);
UpdateValueMap(I, DestReg);
return true;