On 10/15/2015 11:40 AM, Kyrill Tkachov wrote:
The code that analyzes the offsets of the loads/stores doesn't try to
handle load/store-multiple insns.
These appear rather frequently in memory streaming workloads on aarch64
in the form of load-pair/store-pair instructions
i.e. ldp/stp. In RTL, they are created by the sched_fusion pass + a
subsequent peephole and during sched2 they appear
as PARALLEL rtxes of multiple SETs to/from memory.
* sched-int.h (struct autopref_multipass_data_): Remove offset
field. Add min_offset, max_offset, multi_mem_insn_p fields.
* haifa-sched.c (analyze_set_insn_for_autopref): New function.
(autopref_multipass_init): Use it. Handle PARALLEL sets.
(autopref_rank_data): New function.
(autopref_rank_for_schedule): Use it.
(autopref_multipass_dfa_lookahead_guard_1): Likewise.
Looks pretty reasonable to me. Ok to commit with a few changes next
Wednesday unless you hear from Vlad in the meantime (I just want to give
him time to look at it).
+/* Helper for autopref_multipass_init. Given a SET insn in PAT and whether
+ we're expecting a memory WRITE or not, check that the insn is relevant to
+ the autoprefetcher modelling code. Return true iff that is the case.
+ If it is relevant record the base register of the memory op in BASE and
+ the offset in OFFSET. */
Comma before "record". I think I'd just use "SET" rather than "SET
insn", because in my mind an insn is always more than just a (part of a)
pattern.
+static bool
+analyze_set_insn_for_autopref (rtx pat, int write, rtx *base, int *offset)
bool write?
+ /* This insn is relevant for auto-prefetcher.
"the auto-prefetcher".
if (data2->status == AUTOPREF_MULTIPASS_DATA_IRRELEVANT)
return 0;
- if (rtx_equal_p (data1->base, data2->base)
- && data1->offset > data2->offset)
+ bool delay_p = rtx_equal_p (data1->base, data2->base)
+ && autopref_rank_data (data1, data2) > 0;
+ if (delay_p)
If you want to do this you still need parentheses around the multi-line
expression. I'd just keep it inside the if condition.
+ /* Is this a load/store-multiple instruction. */
+ bool multi_mem_insn_p;
Maybe write "True if this is a ..."
Bernd
