[RDF] Do not return register masks in PhysicalRegisterInfo::getAliasSet

Author: Krzysztof Parzyszek

llvm/include/llvm/CodeGen/RDFRegisters.h

@@ -142,7 +142,7 @@ struct PhysicalRegisterInfo {
   }
 
   // Returns the set of aliased physical registers or register masks.
-  // The returned set does not contain register units.
+  // The returned set only contains physical registers (not masks or units).
   std::set<RegisterId> getAliasSet(RegisterId Reg) const;
 
   RegisterRef getRefForUnit(uint32_t U) const {

llvm/lib/CodeGen/RDFRegisters.cpp

@@ -115,22 +115,13 @@ std::set<RegisterId> PhysicalRegisterInfo::getAliasSet(RegisterId Reg) const {
         continue;
       AS.insert(i);
     }
-    for (const uint32_t *RM : RegMasks) {
-      RegisterId MI = getRegMaskId(RM);
-      if (MI != Reg && aliasMM(RegisterRef(Reg), RegisterRef(MI)))
-        AS.insert(MI);
-    }
     return AS;
   }
 
   assert(RegisterRef::isRegId(Reg));
   for (MCRegAliasIterator AI(Reg, &TRI, false); AI.isValid(); ++AI)
     AS.insert(*AI);
-  for (const uint32_t *RM : RegMasks) {
-    RegisterId MI = getRegMaskId(RM);
-    if (aliasRM(RegisterRef(Reg), RegisterRef(MI)))
-      AS.insert(MI);
-  }
+
   return AS;
 }