Extract LaneBitmask into a separate type

Specifically avoid implicit conversions from/to integral types to
avoid potential errors when changing the underlying type. For example,
a typical initialization of a "full" mask was "LaneMask = ~0u", which
would result in a value of 0x00000000FFFFFFFF if the type was extended
to uint64_t.

Differential Revision: https://reviews.llvm.org/D27454

llvm-svn: 289820

1 files changed, 12 insertions, 12 deletions

diff --git a/llvm/lib/CodeGen/DetectDeadLanes.cpp b/llvm/lib/CodeGen/DetectDeadLanes.cpp
index 6dc6de2e742..c92ef03b7eb 100644
--- a/llvm/lib/CodeGen/DetectDeadLanes.cpp
+++ b/llvm/lib/CodeGen/DetectDeadLanes.cpp
@@ -210,7 +210,7 @@ void DetectDeadLanes::addUsedLanesOnOperand(const MachineOperand &MO,
   VRegInfo &MORegInfo = VRegInfos[MORegIdx];
   LaneBitmask PrevUsedLanes = MORegInfo.UsedLanes;
   // Any change at all?
-  if ((UsedLanes & ~PrevUsedLanes) == 0)
+  if ((UsedLanes & ~PrevUsedLanes).none())
     return;
 
   // Set UsedLanes and remember instruction for further propagation.
@@ -303,7 +303,7 @@ void DetectDeadLanes::transferDefinedLanesStep(const MachineOperand &Use,
   VRegInfo &RegInfo = VRegInfos[DefRegIdx];
   LaneBitmask PrevDefinedLanes = RegInfo.DefinedLanes;
   // Any change at all?
-  if ((DefinedLanes & ~PrevDefinedLanes) == 0)
+  if ((DefinedLanes & ~PrevDefinedLanes).none())
     return;
 
   RegInfo.DefinedLanes = PrevDefinedLanes | DefinedLanes;
@@ -356,7 +356,7 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
   // Live-In or unused registers have no definition but are considered fully
   // defined.
   if (!MRI->hasOneDef(Reg))
-    return ~0u;
+    return LaneBitmask::getAll();
 
   const MachineOperand &Def = *MRI->def_begin(Reg);
   const MachineInstr &DefMI = *Def.getParent();
@@ -368,7 +368,7 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
     PutInWorklist(RegIdx);
 
     if (Def.isDead())
-      return 0;
+      return LaneBitmask::getNone();
 
     // COPY/PHI can copy across unrelated register classes (example: float/int)
     // with incompatible subregister structure. Do not include these in the
@@ -376,7 +376,7 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
     const TargetRegisterClass *DefRC = MRI->getRegClass(Reg);
 
     // Determine initially DefinedLanes.
-    LaneBitmask DefinedLanes = 0;
+    LaneBitmask DefinedLanes;
     for (const MachineOperand &MO : DefMI.uses()) {
       if (!MO.isReg() || !MO.readsReg())
         continue;
@@ -386,9 +386,9 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
 
       LaneBitmask MODefinedLanes;
       if (TargetRegisterInfo::isPhysicalRegister(MOReg)) {
-        MODefinedLanes = ~0u;
+        MODefinedLanes = LaneBitmask::getAll();
       } else if (isCrossCopy(*MRI, DefMI, DefRC, MO)) {
-        MODefinedLanes = ~0u;
+        MODefinedLanes = LaneBitmask::getAll();
       } else {
         assert(TargetRegisterInfo::isVirtualRegister(MOReg));
         if (MRI->hasOneDef(MOReg)) {
@@ -410,7 +410,7 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
     return DefinedLanes;
   }
   if (DefMI.isImplicitDef() || Def.isDead())
-    return 0;
+    return LaneBitmask::getNone();
 
   assert(Def.getSubReg() == 0 &&
          "Should not have subregister defs in machine SSA phase");
@@ -418,7 +418,7 @@ LaneBitmask DetectDeadLanes::determineInitialDefinedLanes(unsigned Reg) {
 }
 
 LaneBitmask DetectDeadLanes::determineInitialUsedLanes(unsigned Reg) {
-  LaneBitmask UsedLanes = 0;
+  LaneBitmask UsedLanes = LaneBitmask::getNone();
   for (const MachineOperand &MO : MRI->use_nodbg_operands(Reg)) {
     if (!MO.readsReg())
       continue;
@@ -462,7 +462,7 @@ bool DetectDeadLanes::isUndefRegAtInput(const MachineOperand &MO,
                                         const VRegInfo &RegInfo) const {
   unsigned SubReg = MO.getSubReg();
   LaneBitmask Mask = TRI->getSubRegIndexLaneMask(SubReg);
-  return (RegInfo.DefinedLanes & RegInfo.UsedLanes & Mask) == 0;
+  return (RegInfo.DefinedLanes & RegInfo.UsedLanes & Mask).none();
 }
 
 bool DetectDeadLanes::isUndefInput(const MachineOperand &MO,
@@ -482,7 +482,7 @@ bool DetectDeadLanes::isUndefInput(const MachineOperand &MO,
 
   const VRegInfo &DefRegInfo = VRegInfos[DefRegIdx];
   LaneBitmask UsedLanes = transferUsedLanes(MI, DefRegInfo.UsedLanes, MO);
-  if (UsedLanes != 0)
+  if (!UsedLanes.none())
     return false;
 
   unsigned MOReg = MO.getReg();
@@ -546,7 +546,7 @@ bool DetectDeadLanes::runOnce(MachineFunction &MF) {
           continue;
         unsigned RegIdx = TargetRegisterInfo::virtReg2Index(Reg);
         const VRegInfo &RegInfo = VRegInfos[RegIdx];
-        if (MO.isDef() && !MO.isDead() && RegInfo.UsedLanes == 0) {
+        if (MO.isDef() && !MO.isDead() && RegInfo.UsedLanes.none()) {
           DEBUG(dbgs() << "Marking operand '" << MO << "' as dead in " << MI);
           MO.setIsDead();
         }