const runtime.traceArgCountShift

5 uses

	runtime (current package)
		trace.go#L129: 	traceArgCountShift = 6
		trace.go#L638: 		buf.byte(traceEvFrequency | 0<<traceArgCountShift)
		trace.go#L818: 	buf.byte(ev | narg<<traceArgCountShift)
		trace.go#L1083: 	bufp.byte(traceEvBatch | 1<<traceArgCountShift)
		trace.go#L1312: 			buf.byte(traceEvStack | 3<<traceArgCountShift)