Refactor unfoldings

There are two main refactorings here

1.  Move the uf_arity field
       out of CoreUnfolding
       into UnfWhen
    It's a lot tidier there.  If I've got this right, no behaviour
    should change.

2.  Define specUnfolding and use it in DsBinds and Specialise
     a) commons-up some shared code
     b) makes sure that Specialise correctly specialises DFun
        unfoldings (which it didn't before)

The two got put together because both ended up interacting in the
specialiser.

They cause zero difference to nofib.

11 files changed, 57 insertions, 61 deletions

diff --git a/testsuite/tests/deSugar/should_compile/T2431.stderr b/testsuite/tests/deSugar/should_compile/T2431.stderr
index c40b603d3f..f9b07605b9 100644
--- a/testsuite/tests/deSugar/should_compile/T2431.stderr
+++ b/testsuite/tests/deSugar/should_compile/T2431.stderr
@@ -6,9 +6,9 @@ T2431.$WRefl [InlPrag=INLINE] :: forall a. a T2431.:~: a
 [GblId[DataConWrapper],
  Caf=NoCafRefs,
  Str=DmdType,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=0, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=False,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=0,unsat_ok=False,boring_ok=False)
          Tmpl= \ (@ a) -> T2431.Refl @ a @ a @~ <a>_N}]
 T2431.$WRefl = \ (@ a) -> T2431.Refl @ a @ a @~ <a>_N
 
diff --git a/testsuite/tests/numeric/should_compile/T7116.stdout b/testsuite/tests/numeric/should_compile/T7116.stdout
index 549ed488aa..9e5d19e3e0 100644
--- a/testsuite/tests/numeric/should_compile/T7116.stdout
+++ b/testsuite/tests/numeric/should_compile/T7116.stdout
@@ -7,9 +7,9 @@ T7116.dl :: GHC.Types.Double -> GHC.Types.Double
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U(U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (x [Occ=Once!] :: GHC.Types.Double) ->
                  case x of _ [Occ=Dead] { GHC.Types.D# y ->
                  GHC.Types.D# (GHC.Prim.+## y y)
@@ -25,9 +25,9 @@ T7116.dr :: GHC.Types.Double -> GHC.Types.Double
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U(U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (x [Occ=Once!] :: GHC.Types.Double) ->
                  case x of _ [Occ=Dead] { GHC.Types.D# x1 ->
                  GHC.Types.D# (GHC.Prim.+## x1 x1)
@@ -39,9 +39,9 @@ T7116.fl :: GHC.Types.Float -> GHC.Types.Float
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U(U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (x [Occ=Once!] :: GHC.Types.Float) ->
                  case x of _ [Occ=Dead] { GHC.Types.F# y ->
                  GHC.Types.F# (GHC.Prim.plusFloat# y y)
@@ -57,9 +57,9 @@ T7116.fr :: GHC.Types.Float -> GHC.Types.Float
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U(U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (x [Occ=Once!] :: GHC.Types.Float) ->
                  case x of _ [Occ=Dead] { GHC.Types.F# x1 ->
                  GHC.Types.F# (GHC.Prim.plusFloat# x1 x1)
diff --git a/testsuite/tests/simplCore/should_compile/T3717.stderr b/testsuite/tests/simplCore/should_compile/T3717.stderr
index 4522fb5d91..73b73effb9 100644
--- a/testsuite/tests/simplCore/should_compile/T3717.stderr
+++ b/testsuite/tests/simplCore/should_compile/T3717.stderr
@@ -18,9 +18,9 @@ T3717.foo [InlPrag=INLINE[0]] :: GHC.Types.Int -> GHC.Types.Int
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S(S),1*U(1*U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (w [Occ=Once!] :: GHC.Types.Int) ->
                  case w of _ [Occ=Dead] { GHC.Types.I# ww1 [Occ=Once] ->
                  case T3717.$wfoo ww1 of ww2 { __DEFAULT -> GHC.Types.I# ww2 }
diff --git a/testsuite/tests/simplCore/should_compile/T4908.stderr b/testsuite/tests/simplCore/should_compile/T4908.stderr
index 3acef2fefd..2f80625e98 100644
--- a/testsuite/tests/simplCore/should_compile/T4908.stderr
+++ b/testsuite/tests/simplCore/should_compile/T4908.stderr
@@ -28,9 +28,8 @@ T4908.$wf
  Arity=2,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U><L,1*U(A,U(U))>,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=2, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=IF_ARGS [30 20] 101 20}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True, Guidance=IF_ARGS [30 20] 101 20}]
 T4908.$wf =
   \ (ww :: GHC.Prim.Int#) (w :: (GHC.Types.Int, GHC.Types.Int)) ->
     case ww of ds {
@@ -53,9 +52,9 @@ T4908.f [InlPrag=INLINE[0]]
  Arity=2,
  Caf=NoCafRefs,
  Str=DmdType <S(S),1*U(1*U)><L,1*U(A,U(U))>,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=2, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=2,unsat_ok=True,boring_ok=False)
          Tmpl= \ (w [Occ=Once!] :: GHC.Types.Int)
                  (w1 [Occ=Once] :: (GHC.Types.Int, GHC.Types.Int)) ->
                  case w of _ [Occ=Dead] { GHC.Types.I# ww1 [Occ=Once] ->
diff --git a/testsuite/tests/simplCore/should_compile/T4930.stderr b/testsuite/tests/simplCore/should_compile/T4930.stderr
index 9570b7b98a..5f0aad2525 100644
--- a/testsuite/tests/simplCore/should_compile/T4930.stderr
+++ b/testsuite/tests/simplCore/should_compile/T4930.stderr
@@ -14,9 +14,9 @@ T4930.foo :: GHC.Types.Int -> GHC.Types.Int
 [GblId,
  Arity=1,
  Str=DmdType <S,1*U(U)>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (n [Occ=Once!] :: GHC.Types.Int) ->
                  case n of _ [Occ=Dead] { GHC.Types.I# x ->
                  case GHC.Prim.tagToEnum# @ GHC.Types.Bool (GHC.Prim.<# x 5)
diff --git a/testsuite/tests/simplCore/should_compile/T7360.stderr b/testsuite/tests/simplCore/should_compile/T7360.stderr
index 9a5896a8d4..c6c0563cac 100644
--- a/testsuite/tests/simplCore/should_compile/T7360.stderr
+++ b/testsuite/tests/simplCore/should_compile/T7360.stderr
@@ -7,9 +7,9 @@ T7360.$WFoo3 [InlPrag=INLINE] :: GHC.Types.Int -> T7360.Foo
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,U>m3,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=False,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=False,boring_ok=False)
          Tmpl= \ (dt [Occ=Once!] :: GHC.Types.Int) ->
                  case dt of _ [Occ=Dead] { GHC.Types.I# dt [Occ=Once] ->
                  T7360.Foo3 dt
@@ -29,27 +29,25 @@ T7360.fun1 =
 T7360.fun4 :: ()
 [GblId,
  Str=DmdType,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=0, Value=False,
-         ConLike=False, WorkFree=False, Expandable=False,
-         Guidance=IF_ARGS [] 20 0}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=False, ConLike=False,
+         WorkFree=False, Expandable=False, Guidance=IF_ARGS [] 20 0}]
 T7360.fun4 = T7360.fun1 T7360.Foo1
 
 T7360.fun3 :: GHC.Types.Int
 [GblId,
  Caf=NoCafRefs,
  Str=DmdType m,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=0, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=IF_ARGS [] 10 20}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True, Guidance=IF_ARGS [] 10 20}]
 T7360.fun3 = GHC.Types.I# 0
 
 T7360.fun2 :: forall a. [a] -> ((), GHC.Types.Int)
 [GblId,
  Arity=1,
  Str=DmdType <L,1*U>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (@ a) (x [Occ=Once!] :: [a]) ->
                  (T7360.fun4,
                   case x of wild {
diff --git a/testsuite/tests/simplCore/should_compile/T7785.stderr b/testsuite/tests/simplCore/should_compile/T7785.stderr
index d32eacce48..c80738f4c3 100644
--- a/testsuite/tests/simplCore/should_compile/T7785.stderr
+++ b/testsuite/tests/simplCore/should_compile/T7785.stderr
@@ -1,6 +1,6 @@
 
 ==================== Tidy Core rules ====================
-"SPEC Foo.shared [[]]" [ALWAYS]
+"SPEC Foo.shared @ []" [ALWAYS]
     forall ($dMyFunctor :: MyFunctor []) (irred :: Domain [] Int).
       shared @ [] $dMyFunctor irred
       = bar_$sshared
diff --git a/testsuite/tests/simplCore/should_compile/T8848.stderr b/testsuite/tests/simplCore/should_compile/T8848.stderr
index ed815141b5..c17d5994c1 100644
--- a/testsuite/tests/simplCore/should_compile/T8848.stderr
+++ b/testsuite/tests/simplCore/should_compile/T8848.stderr
@@ -14,4 +14,6 @@ Rule fired: Class op <*>
 Rule fired: Class op $p1Applicative
 Rule fired: Class op fmap
 Rule fired: Class op <*>
-Rule fired: SPEC T8848.$fFunctorShape ['T8848.Z]
+Rule fired: SPEC $cfmap @ 'T8848.Z
+Rule fired: SPEC $c<$ @ 'T8848.Z
+Rule fired: SPEC T8848.$fFunctorShape @ 'T8848.Z
diff --git a/testsuite/tests/simplCore/should_compile/all.T b/testsuite/tests/simplCore/should_compile/all.T
index c4c32ccd8b..d8518f6264 100644
--- a/testsuite/tests/simplCore/should_compile/all.T
+++ b/testsuite/tests/simplCore/should_compile/all.T
@@ -202,6 +202,6 @@ test('T8832',
      run_command,
      ['$MAKE -s --no-print-directory T8832 T8832_WORDSIZE_OPTS=' +
       ('-DT8832_WORDSIZE_64' if wordsize(64) else '')])
-test('T8848', only_ways(['optasm']), compile, ['-ddump-rule-firings'])
+test('T8848', only_ways(['optasm']), compile, ['-ddump-rule-firings -dsuppress-uniques'])
 test('T8848a', only_ways(['optasm']), compile, ['-ddump-rules'])
 test('T8331', only_ways(['optasm']), compile, ['-ddump-rules'])
diff --git a/testsuite/tests/simplCore/should_compile/spec-inline.stderr b/testsuite/tests/simplCore/should_compile/spec-inline.stderr
index 869017653f..4b48ee3e8d 100644
--- a/testsuite/tests/simplCore/should_compile/spec-inline.stderr
+++ b/testsuite/tests/simplCore/should_compile/spec-inline.stderr
@@ -48,9 +48,8 @@ Roman.$wgo
 [GblId,
  Arity=2,
  Str=DmdType <S,1*U><S,1*U>,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=2, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=IF_ARGS [60 30] 256 0}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True, Guidance=IF_ARGS [60 30] 256 0}]
 Roman.$wgo =
   \ (w :: Data.Maybe.Maybe GHC.Types.Int)
     (w1 :: Data.Maybe.Maybe GHC.Types.Int) ->
@@ -99,9 +98,9 @@ Roman.foo_go [InlPrag=INLINE[0]]
 [GblId,
  Arity=2,
  Str=DmdType <S,1*U><S,1*U>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=2, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=2,unsat_ok=True,boring_ok=False)
          Tmpl= \ (w [Occ=Once] :: Data.Maybe.Maybe GHC.Types.Int)
                  (w1 [Occ=Once] :: Data.Maybe.Maybe GHC.Types.Int) ->
                  case Roman.$wgo w w1 of ww { __DEFAULT -> GHC.Types.I# ww }}]
@@ -114,18 +113,16 @@ Roman.foo2 :: GHC.Types.Int
 [GblId,
  Caf=NoCafRefs,
  Str=DmdType m,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=0, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=IF_ARGS [] 10 20}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True, Guidance=IF_ARGS [] 10 20}]
 Roman.foo2 = GHC.Types.I# 6
 
 Roman.foo1 :: Data.Maybe.Maybe GHC.Types.Int
 [GblId,
  Caf=NoCafRefs,
  Str=DmdType m2,
- Unf=Unf{Src=<vanilla>, TopLvl=True, Arity=0, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=IF_ARGS [] 10 20}]
+ Unf=Unf{Src=<vanilla>, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True, Guidance=IF_ARGS [] 10 20}]
 Roman.foo1 = Data.Maybe.Just @ GHC.Types.Int Roman.foo2
 
 Roman.foo :: GHC.Types.Int -> GHC.Types.Int
@@ -133,9 +130,9 @@ Roman.foo :: GHC.Types.Int -> GHC.Types.Int
  Arity=1,
  Caf=NoCafRefs,
  Str=DmdType <S,1*U>m,
- Unf=Unf{Src=InlineStable, TopLvl=True, Arity=1, Value=True,
-         ConLike=True, WorkFree=True, Expandable=True,
-         Guidance=ALWAYS_IF(unsat_ok=True,boring_ok=False)
+ Unf=Unf{Src=InlineStable, TopLvl=True, Value=True, ConLike=True,
+         WorkFree=True, Expandable=True,
+         Guidance=ALWAYS_IF(arity=1,unsat_ok=True,boring_ok=False)
          Tmpl= \ (n [Occ=Once!] :: GHC.Types.Int) ->
                  case n of n1 { GHC.Types.I# _ [Occ=Dead] ->
                  Roman.foo_go (Data.Maybe.Just @ GHC.Types.Int n1) Roman.foo1
diff --git a/testsuite/tests/simplCore/should_run/T2486.stderr b/testsuite/tests/simplCore/should_run/T2486.stderr
index c85297c5cb..52f5533673 100644
--- a/testsuite/tests/simplCore/should_run/T2486.stderr
+++ b/testsuite/tests/simplCore/should_run/T2486.stderr
@@ -1,18 +1,18 @@
 
 ==================== Tidy Core rules ====================
-"SPEC Main.fib [GHC.Types.Double]" [ALWAYS]
+"SPEC Main.fib @ GHC.Types.Double" [ALWAYS]
     forall ($dNum :: Num Double) ($dOrd :: Ord Double).
       fib @ Double $dNum $dOrd
       = fib_$sfib1
-"SPEC Main.fib [GHC.Types.Int]" [ALWAYS]
+"SPEC Main.fib @ GHC.Types.Int" [ALWAYS]
     forall ($dNum :: Num Int) ($dOrd :: Ord Int).
       fib @ Int $dNum $dOrd
       = fib_$sfib
-"SPEC Main.tak [GHC.Types.Double]" [ALWAYS]
+"SPEC Main.tak @ GHC.Types.Double" [ALWAYS]
     forall ($dNum :: Num Double) ($dOrd :: Ord Double).
       tak @ Double $dNum $dOrd
       = tak_$stak1
-"SPEC Main.tak [GHC.Types.Int]" [ALWAYS]
+"SPEC Main.tak @ GHC.Types.Int" [ALWAYS]
     forall ($dNum :: Num Int) ($dOrd :: Ord Int).
       tak @ Int $dNum $dOrd
       = tak_$stak