haifa-sched.c

[phani narasimhan venkata sesha myreddy]

sir,
i am using gcc to study the scheduling of ultrasparc.

The file haifa-sched.c contains the global variable
"last_scheduled_insn".
It should be an array of ISSUE_RATE.

The function schedule_block() updates the "last_scheduled_insn"
whenever an insn is moved from the ready list to the fired list.

For super-scalars like ultrasparc, where the issue-rate is 4
the last_sheduled_insn should be an array of 4.

SHED_SORT->qsort->rank_for_schedule()
uses the last_scheduled_insn, for calculating tmp_class and
sorts the insns based on the value returned by the insn_cost().

If  last_scheduled_insn is made an array of the ISSUE_RATE
and tmp_class+= tmp_class, a more accurate value of the data_hazard
of the insn can be obtained in the rank_of_schedule().

sincierly,
phani.