Add Jitspewing control for tracelogger data. This can be enabled from the profiler or from the JS shell. Usage is as follows:
From browser (ION_SPEW_FILENAME is recommended here to stdout doesn't get clobbered by each process):
- JS_TRACE_LOGGING=1 IONFLAGS=tracelogger ION_SPEW_FILENAME=tracelogger ./mach run
- Enable JSTracer feature in profiler addon
- Start profiling and ctrl+shift+2 to view profile, and the data will be automatically spewed during profile collection.
- JS_TRACE_LOGGING=1 IONFLAGS=tracelogger dist/bin/js test.js
- Data is automatically spewed to stdout when the shell exits, or use ION_SPEW_FILENAME.
There is an optional environment variable JS_TRACELOGGER_SPEW that can be used to emit specific events, for example JS_TRACELOGGER_SPEW="Interpreter,Baseline,GC" will emit only those specific events along with the script and self time of each script.
The structured spewer is also supported with SPEW=tracelogger, and this will emit the tracelogger data for every recorded event.