Simplify some more getAliasSet callers.

MCRegAliasIterator can include Reg itself in the list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157848 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocFast.cpp b/lib/CodeGen/RegAllocFast.cpp
index b383222..8a22e63 100644
--- a/lib/CodeGen/RegAllocFast.cpp
+++ b/lib/CodeGen/RegAllocFast.cpp
@@ -711,13 +711,10 @@
     if (!MO.isReg() || !MO.isDef()) continue;
     unsigned Reg = MO.getReg();
     if (!Reg || !TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
-    UsedInInstr.set(Reg);
-    if (ThroughRegs.count(PhysRegState[Reg]))
-      definePhysReg(MI, Reg, regFree);
-    for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS) {
-      UsedInInstr.set(*AS);
-      if (ThroughRegs.count(PhysRegState[*AS]))
-        definePhysReg(MI, *AS, regFree);
+    for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+      UsedInInstr.set(*AI);
+      if (ThroughRegs.count(PhysRegState[*AI]))
+        definePhysReg(MI, *AI, regFree);
     }
   }
 
@@ -1036,9 +1033,8 @@
         if (!Reg || !TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
         // Look for physreg defs and tied uses.
         if (!MO.isDef() && !MI->isRegTiedToDefOperand(i)) continue;
-        UsedInInstr.set(Reg);
-        for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS)
-          UsedInInstr.set(*AS);
+        for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
+          UsedInInstr.set(*AI);
       }
     }