On Mon, 22 Oct 2012, Richard Sandiford wrote:
> > The loop probes at FIRST + N * PROBE_INTERVAL for values of N from 1 until
> > it
> > is equal to ROUNDED_SIZE, inclusive, so FIRST + SIZE is always probed.
>
> Doh! But in that case, rather than:
>
> 1:
> beq r1,r2,2f
> addiu r1,r1,interval
> b 1b
> sw $0,0(r1)
> 2:
>
> why not just:
>
> 1:
> addiu r1,r1,interval
> bne r1,r2,1b
> sw $0,0(r1)
>
> ?
For the record that can be easily rewritten to support the MIPS16 mode,
e.g.:
move $1,r2
1:
d/addiu r1,interval
li r2,0
sw/sd r2,0(r1)
move r2,$1
cmp r1,r2
btnez 1b
with $2 and $3 used as temporaries (in addition to $1) as these are I
believe available in MIPS16 prologues ($1 obviously is). The juggling
with $1 can be avoided if the probe used need not be zero (need it?).
The range of <interval> supported by the machine instruction encodings
available is the same as for the standard MIPS or microMIPS mode.
If we care about MIPS16 support, that is.
Maciej
