Re: Fix comments in instr_time.h and remove an unneeded cast to int64

Heikki Linnakangas <hlinnaka@iki.fi> writes:
> Hmm, ok I see. Then I propose:

> 1. Revert
> 2. Just fix the comment to say int64 instead of uint64.

Yeah, it's probably reasonable to specify the output as int64
not uint64 (especially since it looks like that's what the
macros actually produce).

            regards, tom lane