Subject: re: sys/lib/libsa: Cleanup and making stuff "smaller".
To: matthew green <mrg@eterna.com.au>
From: Krister Walfridsson <cato@df.lth.se>
List: tech-kern
Date: 02/23/1999 08:55:08
On Tue, 23 Feb 1999, matthew green wrote:
>
> Cool. -Os reduced the code size from 7584 bytes to 7520 bytes (saving
> 64 bytes), but adding -fno-gcse after that increased code size by 16
> bytes.
>
> is this surprising? i mean, the E in GSCE is *elimination*...
Yes, but egcs is using "Partial Redundance Elimination" (PRE) when doing
GCSE, and that tend to increase the code size to improve the runtime
performance.
But I just checked the documentation. -Os disables PRE and does
"classic GCSE" instead, so you are right. It isn't surprising that
-fno-gcse increases the size slightly.
/Krister