replace TZ with TrailZero0

Author: Macsen Casaus

llvm/lib/Support/KnownBits.cpp

@@ -898,14 +898,13 @@ KnownBits KnownBits::mul(const KnownBits &LHS, const KnownBits &RHS,
     }
 
     // If X has TZ trailing zeroes, then bit (2 * TZ + 1) must be zero.
-    unsigned TZ = (~LHS.Zero).countr_zero();
-    unsigned TwoTZP1 = 2 * TZ + 1;
+    unsigned TwoTZP1 = 2 * TrailZero0 + 1;
     if (TwoTZP1 < BitWidth)
       Res.Zero.setBit(TwoTZP1);
 
     // If X has exactly TZ trailing zeros, then bit (2 * TZ + 2) must also be
     // zero.
-    if (TZ < BitWidth && LHS.One[TZ]) {
+    if (TrailZero0 < BitWidth && LHS.One[TrailZero0]) {
       unsigned TwoTZP2 = TwoTZP1 + 1;
       if (TwoTZP2 < BitWidth)
         Res.Zero.setBit(TwoTZP2);