Unfillable branch delay slots

[Greg McGary]

Joern Rennecke <amylaar@cambridge.redhat.com> writes:

> > My MIPS-like port fails to generate NOP to fill a delay slot when no
> > useful insn will fit.  I don't see any mention of this case in the
> > GCC manual.  How is this supposed to be done?
> 
> Your output pattern in the .md file is supposed to emit the nop.

How does it determine when a nop is required?  If the delay-slot
scheduler found something useful for the slot, I don't want to output
a nop.