>From the gcc-4.3.1 manual:
> -fno-sched-interblock
> Don't schedule instructions across basic blocks. This is normally
> enabled by default when scheduling before register allocation,
> i.e. with -fschedule-insns or at -O2 or higher.
>
> -fno-sched-spec
> Don't allow speculative motion of non-load instructions. This is
> normally enabled by default when scheduling before register
> allocation, i.e. with -fschedule-insns or at -O2 or higher.
The meaning of the second sentence for each option cannot be clearly
understood. From reading the man page, I cannot say what the defaults are for
these settings.
In the first case: is scheduling of instructions across basic blocks enabled by
default when [â¦], or is the option to /disable/ it enabled by default when
[â¦]?
In the second case: Is speculative motion of non-load instructions enabled by
default when [â¦], or is /not allowing it/ enabled by default when [â¦]?
Please change the wording to make things clear. Perhaps the meaning can be
expressed without a negation, with a changed sentence structure, and/or with an
additional sentence giving an explanation.
--
Summary: Documentation for some options starting with âno-â
not clear
Product: gcc
Version: 4.3.1
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: other
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: n-roeser at gmx dot net
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36572
