diff options
Diffstat (limited to 'compiler/GHC/Core/Opt/SpecConstr.hs')
| -rw-r--r-- | compiler/GHC/Core/Opt/SpecConstr.hs | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/compiler/GHC/Core/Opt/SpecConstr.hs b/compiler/GHC/Core/Opt/SpecConstr.hs index afd8afc5ea..14fe9bec00 100644 --- a/compiler/GHC/Core/Opt/SpecConstr.hs +++ b/compiler/GHC/Core/Opt/SpecConstr.hs @@ -656,6 +656,11 @@ containers package we have a merge function with this specialization: We give sc_s5lZ and sc_s5m0 a evaluated unfolding since they come out of strict field fields in the Bin constructor. +This is especially important since tag inference can then use this +information to adjust the calling convention of +`$wmerge0_s4UK` to enforce arguments being passed fully evaluated+tagged. +See Note [Tag Inference], Note [Strict Worker Ids] for more information on +how we can take advantage of this. ----------------------------------------------------- Stuff not yet handled @@ -1771,11 +1776,15 @@ spec_one env fn arg_bndrs body (call_pat, rule_number) -- Annotate the variables with the strictness information from -- the function (see Note [Strictness information in worker binders]) - (spec_lam_args, spec_call_args) = mkWorkerArgs fn False - spec_lam_args1 + (spec_lam_args, spec_call_args,_) = mkWorkerArgs fn False + spec_lam_args1 [] spec_body_ty -- mkWorkerArgs: usual w/w hack to avoid generating -- a spec_rhs of unlifted type and no args. + -- Unlike W/W we don't turn functions into strict workers + -- immediately here instead letting tidy handle this. + -- For this reason we can ignore the cbv marks. + -- See Note [Strict Worker Ids]. See Note [Tag Inference]. spec_id = mkLocalId spec_name Many (mkLamTypes spec_lam_args spec_body_ty) |