New assert in haifa-sched.c

[Eric Botcazou]

> Yes, the assert is really checking exactly that.  Several pieces of
> haifa-sched.c assume that the instruction has been recognized during
> scheduler initialization to speed up checking if instruction is normal
> or some kind of use/clobber/asm.

What happens if an instruction hasn't been recognized upon reaching these 
parts of haifa-sched.c?  Will it be only mis-scheduled, i.e. will this only 
result in inferior, but still correct code?  If so, the assertion shouldn't 
be enabled in release mode but only if ENABLE_CHECKING is defined.

-- 
Eric Botcazou