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 runtime information from the trace data stream, the runtime information being 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 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 decoded runtime information sequences from the trace data sequences, the decoded runtime information sequences being associated with a respective section of the program execution flow performed by the DUT, wherein the result-consolidation stage is configured to receive the decoded 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.