1. A trace-data processing device, comprising an input, which is configured to receive at least one source-specific trace data stream that comprises trace messages carrying encoded execution-flow information on a program execution flow performed by a source device under test or under observation, hereinafter DUT; a trace-data processing unit, which is configured to derive from the trace data stream runtime information associated with the program execution flow performed by the DUT, wherein the trace-data processing unit comprises a message-distribution stage, a plurality of parallel message-processing stages, and a result consolidation stage connected with the message-processing stages, wherein the message-distribution stage is configured to distribute the received trace data stream over the message-processing stages in the form of respective trace data sequences that include at least one trace message, wherein the message-processing stages are each configured to generate from the trace data sections decoded runtime information sequences associated with a respective section of the program execution flow performed by the DUT, wherein the result-consolidation stage is configured to receive the runtime information sequences generated by the message-processing stages and to compose and provide at its output runtime information data representing an at least partial reconstruction of the program execution flow performed by the DUT.