- Removed the -aarch64-enable-subreg-liveness flag, since the -enable-subreg-liveness

  flag can already be used to disable liveness tracking.

Author: kmclaughlin-arm

llvm/lib/Target/AArch64/AArch64Subtarget.cpp

@@ -75,9 +75,6 @@ static cl::opt<unsigned> AArch64MinimumJumpTableEntries(
     "aarch64-min-jump-table-entries", cl::init(13), cl::Hidden,
     cl::desc("Set minimum number of entries to use a jump table on AArch64"));
 
-static cl::opt<bool> EnableSubRegLiveness("aarch64-enable-subreg-liveness",
-                                          cl::init(true), cl::Hidden);
-
 unsigned AArch64Subtarget::getVectorInsertExtractBaseCost() const {
   if (OverrideVectorInsertExtractBaseCost.getNumOccurrences() > 0)
     return OverrideVectorInsertExtractBaseCost;
@@ -575,10 +572,6 @@ AArch64Subtarget::getAuthenticatedLRCheckMethod() const {
   return AArch64PAuth::AuthCheckMethod::None;
 }
 
-bool AArch64Subtarget::enableSubRegLiveness() const {
-  return EnableSubRegLiveness;
-}
-
 bool AArch64Subtarget::enableMachinePipeliner() const {
   return getSchedModel().hasInstrSchedModel();
 }

llvm/lib/Target/AArch64/AArch64Subtarget.h

@@ -149,7 +149,7 @@ class AArch64Subtarget final : public AArch64GenSubtargetInfo {
   const Triple &getTargetTriple() const { return TargetTriple; }
   bool enableMachineScheduler() const override { return true; }
   bool enablePostRAScheduler() const override { return usePostRAScheduler(); }
-  bool enableSubRegLiveness() const override;
+  bool enableSubRegLiveness() const override { return true; }
 
   bool enableMachinePipeliner() const override;
   bool useDFAforSMS() const override { return false; }