[DebugLocEntry][nfc] Remove redundant cast

[fdeazeve]

Summary

A cast from DIExpression->DIExpression is not needed.

[fdeazeve]

@StephenTozer I know the code was already there prior to a change you made in this file, but since you were the last person to move this code around, I figured I'd tag you here :)

[aprantl]

I guess this would produce a different assertion if someone had reinterpreted_casted a wrong pointer before passing it in, but I don't think this is a good enough reason to keep this.

llvm/lib/CodeGen/AsmPrinter/DebugLocEntry.h

DbgValueLoc(const DIExpression *Expr, ArrayRef<DbgValueLocEntry> Locs)
       : Expression(Expr), ValueLocEntries(Locs.begin(), Locs.end()),
         IsVariadic(true) {}
 
   DbgValueLoc(const DIExpression *Expr, ArrayRef<DbgValueLocEntry> Locs,
               bool IsVariadic)
       : Expression(Expr), ValueLocEntries(Locs.begin(), Locs.end()),
         IsVariadic(IsVariadic) {
 #ifndef NDEBUG
-    assert(cast<DIExpression>(Expr)->isValid() ||
+    assert(Expr->isValid() ||
            !any_of(Locs, [](auto LE) { return LE.isLocation(); }));
     if (!IsVariadic) {
       assert(ValueLocEntries.size() == 1);
     }
 #endif
   }
 
   DbgValueLoc(const DIExpression *Expr, DbgValueLocEntry Loc)