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author | Cyril SIX <cyril.six@kalray.eu> | 2020-12-15 17:39:43 +0100 |
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committer | Cyril SIX <cyril.six@kalray.eu> | 2020-12-15 17:39:43 +0100 |
commit | e89ddc35d75d682ae6164b32c582d0fe497ef57c (patch) | |
tree | b5fc36ea5caa1313d7a043a156293fcf9713f379 /scheduling/RTLpathScheduleraux.ml | |
parent | dc413cc8b95c4205af4de247de69a166284ecf99 (diff) | |
download | compcert-kvx-e89ddc35d75d682ae6164b32c582d0fe497ef57c.tar.gz compcert-kvx-e89ddc35d75d682ae6164b32c582d0fe497ef57c.zip |
Turning loads into non-trapping when necessary
Diffstat (limited to 'scheduling/RTLpathScheduleraux.ml')
-rw-r--r-- | scheduling/RTLpathScheduleraux.ml | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/scheduling/RTLpathScheduleraux.ml b/scheduling/RTLpathScheduleraux.ml index 66910bdf..80fc766d 100644 --- a/scheduling/RTLpathScheduleraux.ml +++ b/scheduling/RTLpathScheduleraux.ml @@ -4,6 +4,9 @@ open Maps open RTLpathLivegenaux open Registers open Camlcoq +open Machine + +let has_non_trapping_loads = !(Machine.config).has_non_trapping_loads type superblock = { instructions: P.t array; (* pointers to code instructions *) @@ -219,11 +222,24 @@ let sinst_to_rinst = function ) | Send i -> i +let is_a_cb = function Icond _ -> true | _ -> false +let is_a_load = function Iload _ -> true | _ -> false + let apply_schedule code sb new_order = let tc = ref code in let old_order = sb.instructions in - begin + let count_cbs order = + let current_cbs = ref HashedSet.PSet.empty in + let cbs_above = ref PTree.empty in + Array.iter (fun n -> + let inst = get_some @@ PTree.get n code in + if is_a_cb inst then current_cbs := HashedSet.PSet.add n !current_cbs + else if is_a_load inst then cbs_above := PTree.set n !current_cbs !cbs_above + ) order; + !cbs_above + in begin check_order code old_order new_order; + (* First pass - modify the successors, nothing else *) Array.iteri (fun i n' -> let inst' = get_some @@ PTree.get n' code in let iend = Array.length old_order - 1 in @@ -246,6 +262,23 @@ let apply_schedule code sb new_order = @@ rinst_to_sinst inst' in tc := PTree.set (Array.get old_order i) new_inst !tc ) new_order; + (* Second pass - turn the loads into non-trapping when needed, if the architecture supports it *) + if has_non_trapping_loads then begin + (* 1) We remember which CBs are "above" a given load *) + let cbs_above = count_cbs old_order in + (* 2) We do the same for new_order *) + let cbs_above' = count_cbs new_order in + (* 3) We examine each load, turn it into non-trapping if cbs_above is not included in cbs_above' *) + Array.iter (fun n -> + let inst = get_some @@ PTree.get n !tc in + match inst with + | Iload (t,a,b,c,d,s) -> + let pset = get_some @@ PTree.get n cbs_above in + let pset' = get_some @@ PTree.get n cbs_above' in + if not @@ HashedSet.PSet.is_subset pset pset' then tc := PTree.set n (Iload (AST.NOTRAP,a,b,c,d,s)) !tc + | _ -> () + ) old_order + end; !tc end |