In an embodiment, a method includes, in a hardware processor, determining, for a processor instruction, a rule for matching a predicted memory tag. The method further includes determining a predicted memory tag based on applying the rule for matching the predicted memory tag. The method further includes determining an R tag based on applying the rule. The method further includes obtaining an actual memory tag from memory based on an operand of the processor instruction. The method further includes determining whether the predicted memory tag and the actual memory tag match. The method further includes, if the predicted memory tag and actual memory tag match, using the R tag as the R tag output.