vectorise: Put it out of its misery

Poor DPH and its vectoriser have long been languishing; sadly it seems there is
little chance that the effort will be rekindled. Every few years we discuss
what to do with this mass of code and at least once we have agreed that it
should be archived on a branch and removed from `master`. Here we do just that,
eliminating heaps of dead code in the process.

Here we drop the ParallelArrays extension, the vectoriser, and the `vector` and
`primitive` submodules.

Test Plan: Validate

Reviewers: simonpj, simonmar, hvr, goldfire, alanz

Reviewed By: simonmar

Subscribers: goldfire, rwbarton, thomie, mpickering, carter

Differential Revision: https://phabricator.haskell.org/D4761

1 files changed, 3 insertions, 53 deletions

diff --git a/compiler/hsSyn/HsExpr.hs b/compiler/hsSyn/HsExpr.hs
index 19cb70d6f3..96d86c871b 100644
--- a/compiler/hsSyn/HsExpr.hs
+++ b/compiler/hsSyn/HsExpr.hs
@@ -460,18 +460,6 @@ data HsExpr p
                                    -- For OverloadedLists, the fromListN witness
                 [LHsExpr p]
 
-  -- | Syntactic parallel array: [:e1, ..., en:]
-  --
-  --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen' @'[:'@,
-  --              'ApiAnnotation.AnnDotdot','ApiAnnotation.AnnComma',
-  --              'ApiAnnotation.AnnVbar'
-  --              'ApiAnnotation.AnnClose' @':]'@
-
-  -- For details on above see note [Api annotations] in ApiAnnotation
-  | ExplicitPArr
-                (XExplicitPArr p) -- type of elements of the parallel array
-                [LHsExpr p]
-
   -- | Record construction
   --
   --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen' @'{'@,
@@ -522,24 +510,6 @@ data HsExpr p
                                   -- For OverloadedLists, the fromList witness
                 (ArithSeqInfo p)
 
-  -- | Arithmetic sequence for parallel array
-  --
-  -- > [:e1..e2:] or [:e1, e2..e3:]
-  --
-  --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen' @'[:'@,
-  --              'ApiAnnotation.AnnComma','ApiAnnotation.AnnDotdot',
-  --              'ApiAnnotation.AnnVbar',
-  --              'ApiAnnotation.AnnClose' @':]'@
-
-  -- For details on above see note [Api annotations] in ApiAnnotation
-  | PArrSeq
-                (XPArrSeq p)
-                (ArithSeqInfo p)
-
-  -- | - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen' @'{-\# SCC'@,
-  --             'ApiAnnotation.AnnVal' or 'ApiAnnotation.AnnValStr',
-  --              'ApiAnnotation.AnnClose' @'\#-}'@
-
   -- For details on above see note [Api annotations] in ApiAnnotation
   | HsSCC       (XSCC p)
                 SourceText            -- Note [Pragma source text] in BasicTypes
@@ -781,10 +751,6 @@ type instance XExplicitList  GhcPs = NoExt
 type instance XExplicitList  GhcRn = NoExt
 type instance XExplicitList  GhcTc = Type
 
-type instance XExplicitPArr  GhcPs = NoExt
-type instance XExplicitPArr  GhcRn = NoExt
-type instance XExplicitPArr  GhcTc = Type
-
 type instance XRecordCon     GhcPs = NoExt
 type instance XRecordCon     GhcRn = NoExt
 type instance XRecordCon     GhcTc = RecordConTc
@@ -801,10 +767,6 @@ type instance XArithSeq      GhcPs = NoExt
 type instance XArithSeq      GhcRn = NoExt
 type instance XArithSeq      GhcTc = PostTcExpr
 
-type instance XPArrSeq       GhcPs = NoExt
-type instance XPArrSeq       GhcRn = NoExt
-type instance XPArrSeq       GhcTc = PostTcExpr
-
 type instance XSCC           (GhcPass _) = NoExt
 type instance XCoreAnn       (GhcPass _) = NoExt
 type instance XBracket       (GhcPass _) = NoExt
@@ -1111,9 +1073,6 @@ ppr_expr (HsDo _ do_or_list_comp (L _ stmts)) = pprDo do_or_list_comp stmts
 ppr_expr (ExplicitList _ _ exprs)
   = brackets (pprDeeperList fsep (punctuate comma (map ppr_lexpr exprs)))
 
-ppr_expr (ExplicitPArr _ exprs)
-  = paBrackets (pprDeeperList fsep (punctuate comma (map ppr_lexpr exprs)))
-
 ppr_expr (RecordCon { rcon_con_name = con_id, rcon_flds = rbinds })
   = hang (ppr con_id) 2 (ppr rbinds)
 
@@ -1125,7 +1084,6 @@ ppr_expr (ExprWithTySig sig expr)
          4 (ppr sig)
 
 ppr_expr (ArithSeq _ _ info) = brackets (ppr info)
-ppr_expr (PArrSeq  _ info)   = paBrackets (ppr info)
 
 ppr_expr (EWildPat _)     = char '_'
 ppr_expr (ELazyPat _ e)   = char '~' <> ppr e
@@ -1279,11 +1237,9 @@ hsExprNeedsParens p = go
       | isListCompExpr sc             = False
       | otherwise                     = p > topPrec
     go (ExplicitList{})               = False
-    go (ExplicitPArr{})               = False
     go (RecordUpd{})                  = False
     go (ExprWithTySig{})              = p > topPrec
     go (ArithSeq{})                   = False
-    go (PArrSeq{})                    = False
     go (EWildPat{})                   = False
     go (ELazyPat{})                   = False
     go (EAsPat{})                     = False
@@ -1891,14 +1847,14 @@ type GhciStmt   id = Stmt  id (LHsExpr id)
 
 -- For details on above see note [Api annotations] in ApiAnnotation
 data StmtLR idL idR body -- body should always be (LHs**** idR)
-  = LastStmt  -- Always the last Stmt in ListComp, MonadComp, PArrComp,
+  = LastStmt  -- Always the last Stmt in ListComp, MonadComp,
               -- and (after the renamer) DoExpr, MDoExpr
               -- Not used for GhciStmtCtxt, PatGuard, which scope over other stuff
           (XLastStmt idL idR body)
           body
           Bool               -- True <=> return was stripped by ApplicativeDo
           (SyntaxExpr idR)   -- The return operator, used only for
-                             -- MonadComp For ListComp, PArrComp, we
+                             -- MonadComp For ListComp we
                              -- use the baked-in 'return' For DoExpr,
                              -- MDoExpr, we don't apply a 'return' at
                              -- all See Note [Monad Comprehensions] |
@@ -2374,7 +2330,6 @@ pprDo GhciStmtCtxt  stmts = text "do"  <+> ppr_do_stmts stmts
 pprDo ArrowExpr     stmts = text "do"  <+> ppr_do_stmts stmts
 pprDo MDoExpr       stmts = text "mdo" <+> ppr_do_stmts stmts
 pprDo ListComp      stmts = brackets    $ pprComp stmts
-pprDo PArrComp      stmts = paBrackets  $ pprComp stmts
 pprDo MonadComp     stmts = brackets    $ pprComp stmts
 pprDo _             _     = panic "pprDo" -- PatGuard, ParStmtCxt
 
@@ -2778,7 +2733,6 @@ isPatSynCtxt ctxt =
 data HsStmtContext id
   = ListComp
   | MonadComp
-  | PArrComp                         -- ^Parallel array comprehension
 
   | DoExpr                           -- ^do { ... }
   | MDoExpr                          -- ^mdo { ... }  ie recursive do-expression
@@ -2794,7 +2748,6 @@ deriving instance (Data id) => Data (HsStmtContext id)
 isListCompExpr :: HsStmtContext id -> Bool
 -- Uses syntax [ e | quals ]
 isListCompExpr ListComp          = True
-isListCompExpr PArrComp          = True
 isListCompExpr MonadComp         = True
 isListCompExpr (ParStmtCtxt c)   = isListCompExpr c
 isListCompExpr (TransStmtCtxt c) = isListCompExpr c
@@ -2809,7 +2762,7 @@ isMonadFailStmtContext MDoExpr              = True
 isMonadFailStmtContext GhciStmtCtxt         = True
 isMonadFailStmtContext (ParStmtCtxt ctxt)   = isMonadFailStmtContext ctxt
 isMonadFailStmtContext (TransStmtCtxt ctxt) = isMonadFailStmtContext ctxt
-isMonadFailStmtContext _ = False -- ListComp, PArrComp, PatGuard, ArrowExpr
+isMonadFailStmtContext _ = False -- ListComp, PatGuard, ArrowExpr
 
 matchSeparator :: HsMatchContext id -> SDoc
 matchSeparator (FunRhs {})   = text "="
@@ -2864,7 +2817,6 @@ pprAStmtContext ctxt = article <+> pprStmtContext ctxt
     pp_a  = text "a"
     article = case ctxt of
                   MDoExpr       -> pp_an
-                  PArrComp      -> pp_an
                   GhciStmtCtxt  -> pp_an
                   _             -> pp_a
 
@@ -2876,7 +2828,6 @@ pprStmtContext MDoExpr         = text "'mdo' block"
 pprStmtContext ArrowExpr       = text "'do' block in an arrow command"
 pprStmtContext ListComp        = text "list comprehension"
 pprStmtContext MonadComp       = text "monad comprehension"
-pprStmtContext PArrComp        = text "array comprehension"
 pprStmtContext (PatGuard ctxt) = text "pattern guard for" $$ pprMatchContext ctxt
 
 -- Drop the inner contexts when reporting errors, else we get
@@ -2918,7 +2869,6 @@ matchContextErrString (StmtCtxt ArrowExpr)         = text "'do' block"
 matchContextErrString (StmtCtxt MDoExpr)           = text "'mdo' block"
 matchContextErrString (StmtCtxt ListComp)          = text "list comprehension"
 matchContextErrString (StmtCtxt MonadComp)         = text "monad comprehension"
-matchContextErrString (StmtCtxt PArrComp)          = text "array comprehension"
 
 pprMatchInCtxt :: (OutputableBndrId (GhcPass idR),
                    -- TODO:AZ these constraints do not make sense