For drcachesim post-processing of explicit instr entries such as for filtered traces, do not output non-xfer markers post-instr and just exit back to the main loop instead, to avoid overflowing the buffer with potentially unimited strings of markers before the next filtered instr or memref entry.
For marker output during tracing, add an explicit check and buffer dump when the redzone is hit, as a safety step, even though today's code should not reach it.
Add a release-build check for hitting the buffer size so we can detect pathological missing-post-call stacked function markers. Fully handling that is left for future work.
Issue: #4159