[Hexagon] Disable predicated calls by default

llvm-svn: 302307

llvm/lib/Target/Hexagon/HexagonInstrInfo.cpp

@@ -1467,7 +1467,15 @@ bool HexagonInstrInfo::DefinesPredicate(
 }
 
 bool HexagonInstrInfo::isPredicable(const MachineInstr &MI) const {
-  return MI.getDesc().isPredicable();
+  if (!MI.getDesc().isPredicable())
+    return false;
+
+  if (MI.isCall() || isTailCall(MI)) {
+    const MachineFunction &MF = *MI.getParent()->getParent();
+    if (!MF.getSubtarget<HexagonSubtarget>().usePredicatedCalls())
+      return false;
+  }
+  return true;
 }
 
 bool HexagonInstrInfo::isSchedulingBoundary(const MachineInstr &MI,

llvm/lib/Target/Hexagon/HexagonSubtarget.cpp

@@ -73,6 +73,10 @@ static cl::opt<bool> OverrideLongCalls("hexagon-long-calls",
   cl::Hidden, cl::ZeroOrMore, cl::init(false),
   cl::desc("If present, forces/disables the use of long calls"));
 
+static cl::opt<bool> EnablePredicatedCalls("hexagon-pred-calls",
+  cl::Hidden, cl::ZeroOrMore, cl::init(false),
+  cl::desc("Consider calls to be predicable"));
+
 void HexagonSubtarget::initializeEnvironment() {
   UseMemOps = false;
   ModeIEEERndNear = false;
@@ -257,6 +261,10 @@ bool HexagonSubtarget::enableMachineScheduler() const {
   return true;
 }
 
+bool HexagonSubtarget::usePredicatedCalls() const {
+  return EnablePredicatedCalls;
+}
+
 void HexagonSubtarget::updateLatency(MachineInstr &SrcInst,
       MachineInstr &DstInst, SDep &Dep) const {
   if (Dep.isArtificial()) {

llvm/lib/Target/Hexagon/HexagonSubtarget.h

@@ -104,6 +104,7 @@ public:
   bool useHVXDblOps() const { return UseHVXOps && UseHVXDblOps; }
   bool useHVXSglOps() const { return UseHVXOps && !UseHVXDblOps; }
   bool useLongCalls() const { return UseLongCalls; }
+  bool usePredicatedCalls() const;
 
   bool useBSBScheduling() const { return UseBSBScheduling; }
   bool enableMachineScheduler() const override;