Date: Sat, 14 Sep 1996 00:41:07 -0700 (PDT) From: Bruce Evans <bde> To: CVS-committers, cvs-all, cvs-sys Subject: cvs commit: src/sys/i386/boot/biosboot disk.c sys.c Message-ID: <199609140741.AAA15326@freefall.freebsd.org>
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bde 96/09/14 00:41:07 Modified: sys/i386/boot/biosboot disk.c sys.c Log: Moved instantiation of `poff' to sys.c. It is no longer used in disk.c. Saved a few bytes by copying `dosdev' and/or `name' to local variables. This optimization (for dosdev) was done in one place before but this was lost in the devread() cleanup. This optimization (for dosdev) can almost be done by bogusly declaring dosdev as const, but gcc still often space-pessimizes code like the following: extern const int dosdev; ... foo(dosdev); bar(dosdev); gcc often doesn't bother to copy dosdev to a temporary local because the local would have to be preserved in memory across the call to foo(). OTOH, for extern int dosdev; ... auto int dosdev_copy = dosdev; ... foo(dosdev_copy); bar(dosdev_copy); the copy must be made because foo() might alter dosdev. Revision Changes Path 1.20 +12 -9 src/sys/i386/boot/biosboot/disk.c 1.15 +18 -15 src/sys/i386/boot/biosboot/sys.c
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