+ -- Replace AND by AND THEN, or OR by OR ELSE, if Short_Circuit_And_Or
+ -- is active and the result type is standard Boolean (do not mess with
+ -- ops that return a nonstandard Boolean type, because something strange
+ -- is going on).
+
+ -- Note: you might expect this replacement to be done during expansion,
+ -- but that doesn't work, because when the pragma Short_Circuit_And_Or
+ -- is used, no part of the right operand of an "and" or "or" operator
+ -- should be executed if the left operand would short-circuit the
+ -- evaluation of the corresponding "and then" or "or else". If we left
+ -- the replacement to expansion time, then run-time checks associated
+ -- with such operands would be evaluated unconditionally, due to being
+ -- before the condition prior to the rewriting as short-circuit forms
+ -- during expansion.
+
+ if Short_Circuit_And_Or
+ and then B_Typ = Standard_Boolean
+ and then Nkind_In (N, N_Op_And, N_Op_Or)
+ then
+ if Nkind (N) = N_Op_And then
+ Rewrite (N,
+ Make_And_Then (Sloc (N),
+ Left_Opnd => Relocate_Node (Left_Opnd (N)),
+ Right_Opnd => Relocate_Node (Right_Opnd (N))));
+ Analyze_And_Resolve (N, B_Typ);
+
+ -- Case of OR changed to OR ELSE
+
+ else
+ Rewrite (N,
+ Make_Or_Else (Sloc (N),
+ Left_Opnd => Relocate_Node (Left_Opnd (N)),
+ Right_Opnd => Relocate_Node (Right_Opnd (N))));
+ Analyze_And_Resolve (N, B_Typ);
+ end if;
+
+ -- Return now, since analysis of the rewritten ops will take care of
+ -- other reference bookkeeping and expression folding.
+
+ return;
+ end if;
+