Remove unused LiveVars and SRT fields of StgCase

We also need to update `stgBindHasCafRefs` assertion with this change,
as we no longer have the pre-computed SRT, LiveVars etc. We rename it to
`topStgBindHasCafRefs` and implement it like this:

A non-updatable top-level binding may refer to a CAF by referring to a
top-level definition with CAFs. A top-level definition may have CAFs if
it's updatable. At this point (because this is done after TidyPgm)
top-level Ids (whether imported or defined in this module) are
GlobalIds, so the top-levelness test is easy. (see also comments in the
code)

Reviewers: bgamari, simonpj, austin

Reviewed By: simonpj

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1889

GHC Trac Issues: #11550

3 files changed, 6 insertions, 6 deletions

diff --git a/compiler/codeGen/StgCmm.hs b/compiler/codeGen/StgCmm.hs
index b0dd9b11b8..9d14db9bb8 100644
--- a/compiler/codeGen/StgCmm.hs
+++ b/compiler/codeGen/StgCmm.hs
@@ -141,7 +141,7 @@ cgTopRhs :: DynFlags -> RecFlag -> Id -> StgRhs -> (CgIdInfo, FCode ())
 cgTopRhs dflags _rec bndr (StgRhsCon _cc con args)
   = cgTopRhsCon dflags bndr con args
 
-cgTopRhs dflags rec bndr (StgRhsClosure cc bi fvs upd_flag _srt args body)
+cgTopRhs dflags rec bndr (StgRhsClosure cc bi fvs upd_flag args body)
   = ASSERT(null fvs)    -- There should be no free variables
     cgTopRhsClosure dflags rec bndr cc bi upd_flag args body
 
diff --git a/compiler/codeGen/StgCmmBind.hs b/compiler/codeGen/StgCmmBind.hs
index fde662b317..ea05e8d488 100644
--- a/compiler/codeGen/StgCmmBind.hs
+++ b/compiler/codeGen/StgCmmBind.hs
@@ -210,7 +210,7 @@ cgRhs id (StgRhsCon cc con args)
     buildDynCon id True cc con args
 
 {- See Note [GC recovery] in compiler/codeGen/StgCmmClosure.hs -}
-cgRhs name (StgRhsClosure cc bi fvs upd_flag _srt args body)
+cgRhs name (StgRhsClosure cc bi fvs upd_flag args body)
   = do dflags <- getDynFlags
        mkRhsClosure dflags name cc bi (nonVoidIds fvs) upd_flag args body
 
@@ -268,7 +268,7 @@ mkRhsClosure    dflags bndr _cc _bi
                 expr
   | let strip = snd . stripStgTicksTop (not . tickishIsCode)
   , StgCase (StgApp scrutinee [{-no args-}])
-         _ _ _ _   -- ignore uniq, etc.
+         _   -- ignore bndr
          (AlgAlt _)
          [(DataAlt _, params, _use_mask, sel_expr)] <- strip expr
   , StgApp selectee [{-no args-}] <- strip sel_expr
diff --git a/compiler/codeGen/StgCmmExpr.hs b/compiler/codeGen/StgCmmExpr.hs
index 923450e6f3..0f3898bf81 100644
--- a/compiler/codeGen/StgCmmExpr.hs
+++ b/compiler/codeGen/StgCmmExpr.hs
@@ -71,7 +71,7 @@ cgExpr (StgLit lit)       = do cmm_lit <- cgLit lit
                                emitReturn [CmmLit cmm_lit]
 
 cgExpr (StgLet binds expr)             = do { cgBind binds;     cgExpr expr }
-cgExpr (StgLetNoEscape _ _ binds expr) =
+cgExpr (StgLetNoEscape binds expr) =
   do { u <- newUnique
      ; let join_id = mkBlockId u
      ; cgLneBinds join_id binds
@@ -79,7 +79,7 @@ cgExpr (StgLetNoEscape _ _ binds expr) =
      ; emitLabel join_id
      ; return r }
 
-cgExpr (StgCase expr _live_vars _save_vars bndr _srt alt_type alts) =
+cgExpr (StgCase expr bndr alt_type alts) =
   cgCase expr bndr alt_type alts
 
 cgExpr (StgLam {}) = panic "cgExpr: StgLam"
@@ -140,7 +140,7 @@ cgLetNoEscapeRhsBody
     -> Id
     -> StgRhs
     -> FCode (CgIdInfo, FCode ())
-cgLetNoEscapeRhsBody local_cc bndr (StgRhsClosure cc _bi _ _upd _ args body)
+cgLetNoEscapeRhsBody local_cc bndr (StgRhsClosure cc _bi _ _upd args body)
   = cgLetNoEscapeClosure bndr local_cc cc (nonVoidIds args) body
 cgLetNoEscapeRhsBody local_cc bndr (StgRhsCon cc con args)
   = cgLetNoEscapeClosure bndr local_cc cc [] (StgConApp con args)