Hi,
I wonder what the common configuration for an arm arch is.
Is my understanding correct, when I build a gcc for arm (32-bit) I have
to pass the --with-arch=xxx. Then the compiler is built against this
arch and especially 'tuned' for the corresponding cpu?
E.g, --with-arch=armv7-a gives an -mcpu=cortexa8 and the compiler can
use all the nice features from this cpu set.
Another example, with --with-arch=armv6z it gives -mcpu=arm1176jzs and I
can not use NEON stuff since it is not in this cpu subset, right?
Now when I do not pass the --with-arch I'll end up with code which is
'optimized' for the arm10tdmi aka. --with-arch=armv5? (On linux eabi)
((#define SUBTARGET_CPU_DEFAULT TARGET_CPU_arm10tdmi))
Back to my original question, if a distribution is going to ship an arm
compiler, they always have to pass the --with-arch= switch to match
their wishes?
My question originates from this situation:
- I have an arm-*-freebsd* triplet where I say the minimum
SUBTARGET_CPU_DEFAULT is xx
- I have another triplet, armv6*-*-freebsd* where I want to set another
SUBTARGET_CPU_DEFAULT
and on both configuration/buildsteps I want to avoid to pass the
--with-arch.
Thanks,
Andreas
