Speculative information flow tracking

An apparatus implementing a processor, the apparatus comprising:

• taint-matrix memory situated to store taint data for a taint-source operation when the taint-source operation is performed by the processor;
• and
• control logic that:
• identifies the taint-source operation,
• stores the taint data in the taint-matrix memory, the taint indicating an operation dependent upon the identified taint-source operation, and
• suppresses at least one side effect of the identified taint-source operation until conditional state determining commitment of the taint-source operation is resolved.

A method comprising:

• a step for identifying a taint-source operation performed by a processor;
• a step for associating a taint tag with an operation dependent upon the taint-source operation;
• performing the taint-source operation, causing at least one side effect;
• and
• a step for suppressing the at least one side effect of the taint-source operation until state of the taint-source operation is resolved.