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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: How to avoid an overflow during multiplication?
Date: Sun, 02 Jan 2022 09:08:24 -0800
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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:

[...]

> One further idea..  after posting it occurred to me that there is
> a technique that is guaranteed to give the right answer as long
> as the result fits in 32 bits:
>
>     uint32_t
>     ticks2time( uint32_t ticks, uint16_t tempo, uint16_t scale ){
>         uint32_t  th       = ticks >> 16;
>         uint32_t  th_tempo = th * tempo;
>         uint32_t  tl       = (uint16_t) ticks;
>         return
>             (th_tempo / scale << 16)  +
>             ((th_tempo % scale << 16)  +  tl*tempo) / scale;
>     }

I must recant this earlier comment.  Haste makes bugs.