TcTypeable: Try to reuse KindReps

Here we rework the TcTypeable implementation to reuse KindRep bindings
when possible. This is an attempt at minimizing the impact of Typeable
binding generation by reducing the number of bindings that we produce.

It turns out that this produces some pretty reasonable compiler
allocations improvements. It seems to erase most of the increases
initially introduced by TTypeable in the testsuite. Moreover, nofib
shows,
```
        -1 s.d.                -----          -3.555%
        +1 s.d.                -----          +1.937%
        Average                -----          -0.847%
```

Here are a few of the high-scorers (ignore last column, which is for
D3219),
```
veritas
          Types             88800920         -18.945%         -21.480%

veritas
        Tactics            540766744         -27.256%         -27.338%

sched
           Main            567013384          -4.947%          -5.358%

listcompr
           Main            532300000          -4.273%          -4.572%

listcopy
           Main            537785392          -4.382%          -4.635%

anna
       BaseDefs           1984225032         -10.639%         -10.832%

```
as expected, these tend to be modules with either very many or very
large types.

Test Plan: Validate

Reviewers: austin, dfeuer

Subscribers: simonmar, dfeuer, thomie

Differential Revision: https://phabricator.haskell.org/D3166

7 files changed, 136 insertions, 251 deletions

diff --git a/testsuite/tests/roles/should_compile/Roles1.stderr b/testsuite/tests/roles/should_compile/Roles1.stderr
index 574750ce44..ae4570ab47 100644
--- a/testsuite/tests/roles/should_compile/Roles1.stderr
+++ b/testsuite/tests/roles/should_compile/Roles1.stderr
@@ -33,12 +33,6 @@ Roles1.$tcT7
       (GHC.Types.TrNameS "T7"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep))
 Roles1.$tc'K7
   = GHC.Types.TyCon
       15901479081375327280##
@@ -47,14 +41,6 @@ Roles1.$tc'K7
       (GHC.Types.TrNameS "'K7"#)
       3
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 2)
-      (GHC.Types.KindRepTyConApp
-         Roles1.$tcT7
-         ((:)
-            (GHC.Types.KindRepVar 0)
-            ((:) (GHC.Types.KindRepVar 1) ((:) (GHC.Types.KindRepVar 2) []))))
 Roles1.$tcT6
   = GHC.Types.TyCon
       7244893995195634045##
@@ -63,10 +49,6 @@ Roles1.$tcT6
       (GHC.Types.TrNameS "T6"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles1.$tc'K6
   = GHC.Types.TyCon
       13928703131159360198##
@@ -75,10 +57,6 @@ Roles1.$tc'K6
       (GHC.Types.TrNameS "'K6"#)
       2
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepTyConApp
-      Roles1.$tcT6
-      ((:) (GHC.Types.KindRepVar 0) ((:) (GHC.Types.KindRepVar 1) []))
 Roles1.$tcT5
   = GHC.Types.TyCon
       12033401645911719002##
@@ -87,10 +65,6 @@ Roles1.$tcT5
       (GHC.Types.TrNameS "T5"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles1.$tc'K5
   = GHC.Types.TyCon
       5548842497263642061##
@@ -99,11 +73,6 @@ Roles1.$tc'K5
       (GHC.Types.TrNameS "'K5"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepTyConApp
-         Roles1.$tcT5 ((:) (GHC.Types.KindRepVar 0) []))
 Roles1.$tcT4
   = GHC.Types.TyCon
       15834077582937152787##
@@ -112,14 +81,6 @@ Roles1.$tcT4
       (GHC.Types.TrNameS "T4"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep))
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep))
 Roles1.$tc'K4
   = GHC.Types.TyCon
       10188453925450404995##
@@ -128,13 +89,6 @@ Roles1.$tc'K4
       (GHC.Types.TrNameS "'K4"#)
       2
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepApp
-         (GHC.Types.KindRepVar 0) (GHC.Types.KindRepVar 1))
-      (GHC.Types.KindRepTyConApp
-         Roles1.$tcT4
-         ((:) (GHC.Types.KindRepVar 0) ((:) (GHC.Types.KindRepVar 1) [])))
 Roles1.$tcT3
   = GHC.Types.TyCon
       13341737262627465733##
@@ -143,10 +97,6 @@ Roles1.$tcT3
       (GHC.Types.TrNameS "T3"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles1.$tc'K3
   = GHC.Types.TyCon
       14534968069054730342##
@@ -155,10 +105,6 @@ Roles1.$tc'K3
       (GHC.Types.TrNameS "'K3"#)
       2
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepTyConApp
-      Roles1.$tcT3
-      ((:) (GHC.Types.KindRepVar 0) ((:) (GHC.Types.KindRepVar 1) []))
 Roles1.$tcT2
   = GHC.Types.TyCon
       12900773996789723956##
@@ -167,10 +113,6 @@ Roles1.$tcT2
       (GHC.Types.TrNameS "T2"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles1.$tc'K2
   = GHC.Types.TyCon
       11054915488163123841##
@@ -179,11 +121,6 @@ Roles1.$tc'K2
       (GHC.Types.TrNameS "'K2"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepTyConApp
-         Roles1.$tcT2 ((:) (GHC.Types.KindRepVar 0) []))
 Roles1.$tcT1
   = GHC.Types.TyCon
       13228660854624297872##
@@ -192,10 +129,6 @@ Roles1.$tcT1
       (GHC.Types.TrNameS "T1"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles1.$tc'K1
   = GHC.Types.TyCon
       1265606750138351672##
@@ -204,11 +137,37 @@ Roles1.$tc'K1
       (GHC.Types.TrNameS "'K1"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 1
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 1
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 2
+$krep [InlPrag=[~]] = GHC.Types.KindRepApp $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      Roles1.$tcT7 ((:) $krep ((:) $krep ((:) $krep [])))
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles1.$tcT6 ((:) $krep ((:) $krep []))
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles1.$tcT4 ((:) $krep ((:) $krep []))
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles1.$tcT3 ((:) $krep ((:) $krep []))
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles1.$tcT5 ((:) $krep [])
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles1.$tcT2 ((:) $krep [])
 $krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepVar 0)
-      (GHC.Types.KindRepTyConApp
-         Roles1.$tcT1 ((:) (GHC.Types.KindRepVar 0) []))
+  = GHC.Types.KindRepTyConApp Roles1.$tcT1 ((:) $krep [])
 Roles1.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "Roles1"#)
diff --git a/testsuite/tests/roles/should_compile/Roles13.stderr b/testsuite/tests/roles/should_compile/Roles13.stderr
index 1ea545504b..6a5e31d9c5 100644
--- a/testsuite/tests/roles/should_compile/Roles13.stderr
+++ b/testsuite/tests/roles/should_compile/Roles13.stderr
@@ -1,7 +1,7 @@
 
 ==================== Tidy Core ====================
 Result size of Tidy Core
-  = {terms: 114, types: 43, coercions: 5, joins: 0/0}
+  = {terms: 105, types: 40, coercions: 5, joins: 0/0}
 
 -- RHS size: {terms: 2, types: 2, coercions: 0, joins: 0/0}
 convert1 :: Wrap Age -> Wrap Age
@@ -41,10 +41,27 @@ Roles13.$trModule :: GHC.Types.Module
 [GblId, Caf=NoCafRefs]
 Roles13.$trModule = GHC.Types.Module $trModule2 $trModule4
 
--- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
+-- RHS size: {terms: 3, types: 1, coercions: 0, joins: 0/0}
 $krep :: GHC.Types.KindRep
+[GblId]
+$krep
+  = GHC.Types.KindRepTyConApp
+      GHC.Types.$tcInt (GHC.Types.[] @ GHC.Types.KindRep)
+
+-- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
+$krep1 :: GHC.Types.KindRep
+[GblId, Caf=NoCafRefs]
+$krep1 = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+
+-- RHS size: {terms: 3, types: 0, coercions: 0, joins: 0/0}
+$krep2 :: GHC.Types.KindRep
 [GblId, Caf=NoCafRefs]
-$krep = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+$krep2 = GHC.Types.KindRepFun $krep1 $krep1
+
+-- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
+$krep3 :: GHC.Types.KindRep
+[GblId, Caf=NoCafRefs]
+$krep3 = GHC.Types.KindRepVar 0#
 
 -- RHS size: {terms: 1, types: 0, coercions: 0, joins: 0/0}
 $tcAge1 :: GHC.Prim.Addr#
@@ -66,26 +83,19 @@ Roles13.$tcAge
       Roles13.$trModule
       $tcAge2
       0#
-      $krep
-
--- RHS size: {terms: 3, types: 1, coercions: 0, joins: 0/0}
-$krep1 :: GHC.Types.KindRep
-[GblId]
-$krep1
-  = GHC.Types.KindRepTyConApp
-      GHC.Types.$tcInt (GHC.Types.[] @ GHC.Types.KindRep)
+      $krep1
 
 -- RHS size: {terms: 3, types: 1, coercions: 0, joins: 0/0}
-$krep2 :: GHC.Types.KindRep
+$krep4 :: GHC.Types.KindRep
 [GblId, Caf=NoCafRefs]
-$krep2
+$krep4
   = GHC.Types.KindRepTyConApp
       Roles13.$tcAge (GHC.Types.[] @ GHC.Types.KindRep)
 
 -- RHS size: {terms: 3, types: 0, coercions: 0, joins: 0/0}
-$krep3 :: GHC.Types.KindRep
+$krep5 :: GHC.Types.KindRep
 [GblId]
-$krep3 = GHC.Types.KindRepFun $krep1 $krep2
+$krep5 = GHC.Types.KindRepFun $krep $krep4
 
 -- RHS size: {terms: 1, types: 0, coercions: 0, joins: 0/0}
 $tc'MkAge1 :: GHC.Prim.Addr#
@@ -107,22 +117,7 @@ Roles13.$tc'MkAge
       Roles13.$trModule
       $tc'MkAge2
       0#
-      $krep3
-
--- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
-$krep4 :: GHC.Types.KindRep
-[GblId, Caf=NoCafRefs]
-$krep4 = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
-
--- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
-$krep5 :: GHC.Types.KindRep
-[GblId, Caf=NoCafRefs]
-$krep5 = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
-
--- RHS size: {terms: 3, types: 0, coercions: 0, joins: 0/0}
-$krep6 :: GHC.Types.KindRep
-[GblId, Caf=NoCafRefs]
-$krep6 = GHC.Types.KindRepFun $krep4 $krep5
+      $krep5
 
 -- RHS size: {terms: 1, types: 0, coercions: 0, joins: 0/0}
 $tcWrap1 :: GHC.Prim.Addr#
@@ -144,34 +139,24 @@ Roles13.$tcWrap
       Roles13.$trModule
       $tcWrap2
       0#
-      $krep6
-
--- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
-$krep7 :: GHC.Types.KindRep
-[GblId, Caf=NoCafRefs]
-$krep7 = GHC.Types.KindRepVar 0#
-
--- RHS size: {terms: 2, types: 0, coercions: 0, joins: 0/0}
-$krep8 :: GHC.Types.KindRep
-[GblId, Caf=NoCafRefs]
-$krep8 = GHC.Types.KindRepVar 0#
+      $krep2
 
 -- RHS size: {terms: 3, types: 2, coercions: 0, joins: 0/0}
-$krep9 :: [GHC.Types.KindRep]
+$krep6 :: [GHC.Types.KindRep]
 [GblId, Caf=NoCafRefs]
-$krep9
+$krep6
   = GHC.Types.:
-      @ GHC.Types.KindRep $krep8 (GHC.Types.[] @ GHC.Types.KindRep)
+      @ GHC.Types.KindRep $krep3 (GHC.Types.[] @ GHC.Types.KindRep)
 
 -- RHS size: {terms: 3, types: 0, coercions: 0, joins: 0/0}
-$krep10 :: GHC.Types.KindRep
+$krep7 :: GHC.Types.KindRep
 [GblId, Caf=NoCafRefs]
-$krep10 = GHC.Types.KindRepTyConApp Roles13.$tcWrap $krep9
+$krep7 = GHC.Types.KindRepTyConApp Roles13.$tcWrap $krep6
 
 -- RHS size: {terms: 3, types: 0, coercions: 0, joins: 0/0}
-$krep11 :: GHC.Types.KindRep
+$krep8 :: GHC.Types.KindRep
 [GblId, Caf=NoCafRefs]
-$krep11 = GHC.Types.KindRepFun $krep7 $krep10
+$krep8 = GHC.Types.KindRepFun $krep3 $krep7
 
 -- RHS size: {terms: 1, types: 0, coercions: 0, joins: 0/0}
 $tc'MkWrap1 :: GHC.Prim.Addr#
@@ -193,7 +178,7 @@ Roles13.$tc'MkWrap
       Roles13.$trModule
       $tc'MkWrap2
       1#
-      $krep11
+      $krep8
 
 
 
diff --git a/testsuite/tests/roles/should_compile/Roles14.stderr b/testsuite/tests/roles/should_compile/Roles14.stderr
index 15f61ce9fd..08ca28fecc 100644
--- a/testsuite/tests/roles/should_compile/Roles14.stderr
+++ b/testsuite/tests/roles/should_compile/Roles14.stderr
@@ -20,10 +20,6 @@ Roles12.$tcC2
       (GHC.Types.TrNameS "C2"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint [])
 Roles12.$tc'C:C2
   = GHC.Types.TyCon
       7087988437584478859##
@@ -32,12 +28,13 @@ Roles12.$tc'C:C2
       (GHC.Types.TrNameS "'C:C2"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
 $krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepVar 0) (GHC.Types.KindRepVar 0))
-      (GHC.Types.KindRepTyConApp
-         Roles12.$tcC2 ((:) (GHC.Types.KindRepVar 0) []))
+  = GHC.Types.KindRepTyConApp Roles12.$tcC2 ((:) $krep [])
 Roles12.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "Roles12"#)
diff --git a/testsuite/tests/roles/should_compile/Roles2.stderr b/testsuite/tests/roles/should_compile/Roles2.stderr
index 39ca1ea0a8..b96d17330a 100644
--- a/testsuite/tests/roles/should_compile/Roles2.stderr
+++ b/testsuite/tests/roles/should_compile/Roles2.stderr
@@ -19,10 +19,6 @@ Roles2.$tcT2
       (GHC.Types.TrNameS "T2"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles2.$tc'K2
   = GHC.Types.TyCon
       17395957229042313563##
@@ -31,12 +27,6 @@ Roles2.$tc'K2
       (GHC.Types.TrNameS "'K2"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTyConApp
-         GHC.Ptr.$tcFunPtr ((:) (GHC.Types.KindRepVar 0) []))
-      (GHC.Types.KindRepTyConApp
-         Roles2.$tcT2 ((:) (GHC.Types.KindRepVar 0) []))
 Roles2.$tcT1
   = GHC.Types.TyCon
       10310640733256438505##
@@ -45,10 +35,6 @@ Roles2.$tcT1
       (GHC.Types.TrNameS "T1"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
 Roles2.$tc'K1
   = GHC.Types.TyCon
       16530009231990968394##
@@ -57,12 +43,19 @@ Roles2.$tc'K1
       (GHC.Types.TrNameS "'K1"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp GHC.Ptr.$tcFunPtr ((:) $krep [])
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles2.$tcT2 ((:) $krep [])
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp GHC.Types.$tcIO ((:) $krep [])
 $krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTyConApp
-         GHC.Types.$tcIO ((:) (GHC.Types.KindRepVar 0) []))
-      (GHC.Types.KindRepTyConApp
-         Roles2.$tcT1 ((:) (GHC.Types.KindRepVar 0) []))
+  = GHC.Types.KindRepTyConApp Roles2.$tcT1 ((:) $krep [])
 Roles2.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "Roles2"#)
diff --git a/testsuite/tests/roles/should_compile/Roles3.stderr b/testsuite/tests/roles/should_compile/Roles3.stderr
index af9bc168c7..7f9f1a39d9 100644
--- a/testsuite/tests/roles/should_compile/Roles3.stderr
+++ b/testsuite/tests/roles/should_compile/Roles3.stderr
@@ -41,12 +41,6 @@ Roles3.$tcC4
       (GHC.Types.TrNameS "C4"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint []))
 Roles3.$tcC3
   = GHC.Types.TyCon
       5076086601454991970##
@@ -55,12 +49,6 @@ Roles3.$tcC3
       (GHC.Types.TrNameS "C3"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint []))
 Roles3.$tcC2
   = GHC.Types.TyCon
       7902873224172523979##
@@ -69,12 +57,6 @@ Roles3.$tcC2
       (GHC.Types.TrNameS "C2"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint []))
 Roles3.$tc'C:C2
   = GHC.Types.TyCon
       11218882737915989529##
@@ -83,19 +65,6 @@ Roles3.$tc'C:C2
       (GHC.Types.TrNameS "'C:C2"#)
       2
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTyConApp
-            Data.Type.Equality.$tc~
-            ((:)
-               (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-               ((:) (GHC.Types.KindRepVar 0) ((:) (GHC.Types.KindRepVar 1) []))))
-         (GHC.Types.KindRepFun
-            (GHC.Types.KindRepVar 0) (GHC.Types.KindRepVar 1)))
-      (GHC.Types.KindRepTyConApp
-         Roles3.$tcC2
-         ((:) (GHC.Types.KindRepVar 0) ((:) (GHC.Types.KindRepVar 1) [])))
 Roles3.$tcC1
   = GHC.Types.TyCon
       11013585501375994163##
@@ -104,10 +73,6 @@ Roles3.$tcC1
       (GHC.Types.TrNameS "C1"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint [])
 Roles3.$tc'C:C1
   = GHC.Types.TyCon
       4508088879886988796##
@@ -116,12 +81,23 @@ Roles3.$tc'C:C1
       (GHC.Types.TrNameS "'C:C1"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 1
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      Data.Type.Equality.$tc~ ((:) $krep ((:) $krep ((:) $krep [])))
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles3.$tcC2 ((:) $krep ((:) $krep []))
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
 $krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepVar 0) (GHC.Types.KindRepVar 0))
-      (GHC.Types.KindRepTyConApp
-         Roles3.$tcC1 ((:) (GHC.Types.KindRepVar 0) []))
+  = GHC.Types.KindRepTyConApp Roles3.$tcC1 ((:) $krep [])
 Roles3.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "Roles3"#)
diff --git a/testsuite/tests/roles/should_compile/Roles4.stderr b/testsuite/tests/roles/should_compile/Roles4.stderr
index 389379bad2..205a4d5714 100644
--- a/testsuite/tests/roles/should_compile/Roles4.stderr
+++ b/testsuite/tests/roles/should_compile/Roles4.stderr
@@ -26,10 +26,6 @@ Roles4.$tcC3
       (GHC.Types.TrNameS "C3"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint [])
 Roles4.$tc'C:C3
   = GHC.Types.TyCon
       3133378316178104365##
@@ -38,14 +34,6 @@ Roles4.$tc'C:C3
       (GHC.Types.TrNameS "'C:C3"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepVar 0)
-         (GHC.Types.KindRepTyConApp
-            GHC.Types.$tc[] ((:) (GHC.Types.KindRepVar 0) [])))
-      (GHC.Types.KindRepTyConApp
-         Roles4.$tcC3 ((:) (GHC.Types.KindRepVar 0) []))
 Roles4.$tcC1
   = GHC.Types.TyCon
       13392243382482428602##
@@ -54,10 +42,6 @@ Roles4.$tcC1
       (GHC.Types.TrNameS "C1"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp GHC.Types.$tcConstraint [])
 Roles4.$tc'C:C1
   = GHC.Types.TyCon
       3870707671502302648##
@@ -66,12 +50,19 @@ Roles4.$tc'C:C1
       (GHC.Types.TrNameS "'C:C1"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp GHC.Types.$tc[] ((:) $krep [])
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp Roles4.$tcC3 ((:) $krep [])
 $krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepVar 0) (GHC.Types.KindRepVar 0))
-      (GHC.Types.KindRepTyConApp
-         Roles4.$tcC1 ((:) (GHC.Types.KindRepVar 0) []))
+  = GHC.Types.KindRepTyConApp Roles4.$tcC1 ((:) $krep [])
 Roles4.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "Roles4"#)
diff --git a/testsuite/tests/roles/should_compile/T8958.stderr b/testsuite/tests/roles/should_compile/T8958.stderr
index 5939c69954..22cc6ca7b7 100644
--- a/testsuite/tests/roles/should_compile/T8958.stderr
+++ b/testsuite/tests/roles/should_compile/T8958.stderr
@@ -28,12 +28,6 @@ T8958.$tcMap
       (GHC.Types.TrNameS "Map"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepFun
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-         (GHC.Types.KindRepTYPE GHC.Types.LiftedRep))
 T8958.$tc'MkMap
   = GHC.Types.TyCon
       2942839876828444488##
@@ -42,24 +36,6 @@ T8958.$tc'MkMap
       (GHC.Types.TrNameS "'MkMap"#)
       2
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTyConApp
-         GHC.Types.$tc[]
-         ((:) @ GHC.Types.KindRep
-            (GHC.Types.KindRepTyConApp
-               GHC.Tuple.$tc(,)
-               ((:) @ GHC.Types.KindRep
-                  (GHC.Types.KindRepVar 0)
-                  ((:) @ GHC.Types.KindRep
-                     (GHC.Types.KindRepVar 1) [] @ GHC.Types.KindRep)))
-            [] @ GHC.Types.KindRep))
-      (GHC.Types.KindRepTyConApp
-         T8958.$tcMap
-         ((:) @ GHC.Types.KindRep
-            (GHC.Types.KindRepVar 0)
-            ((:) @ GHC.Types.KindRep
-               (GHC.Types.KindRepVar 1) [] @ GHC.Types.KindRep)))
 T8958.$tcRepresentational
   = GHC.Types.TyCon
       12809567151893673426##
@@ -68,11 +44,6 @@ T8958.$tcRepresentational
       (GHC.Types.TrNameS "Representational"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp
-         GHC.Types.$tcConstraint [] @ GHC.Types.KindRep)
 T8958.$tc'C:Representational
   = GHC.Types.TyCon
       2358772282532242424##
@@ -81,11 +52,6 @@ T8958.$tc'C:Representational
       (GHC.Types.TrNameS "'C:Representational"#)
       1
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepTyConApp
-      T8958.$tcRepresentational
-      ((:) @ GHC.Types.KindRep
-         (GHC.Types.KindRepVar 0) [] @ GHC.Types.KindRep)
 T8958.$tcNominal
   = GHC.Types.TyCon
       12224997609886144634##
@@ -94,11 +60,6 @@ T8958.$tcNominal
       (GHC.Types.TrNameS "Nominal"#)
       0
       $krep
-$krep [InlPrag=[~]]
-  = GHC.Types.KindRepFun
-      (GHC.Types.KindRepTYPE GHC.Types.LiftedRep)
-      (GHC.Types.KindRepTyConApp
-         GHC.Types.$tcConstraint [] @ GHC.Types.KindRep)
 T8958.$tc'C:Nominal
   = GHC.Types.TyCon
       10562260635335201742##
@@ -107,11 +68,34 @@ T8958.$tc'C:Nominal
       (GHC.Types.TrNameS "'C:Nominal"#)
       1
       $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 0
+$krep [InlPrag=[~]] = GHC.Types.KindRepVar 1
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
+$krep [InlPrag=[~]] = GHC.Types.KindRepFun $krep $krep
 $krep [InlPrag=[~]]
   = GHC.Types.KindRepTyConApp
-      T8958.$tcNominal
+      GHC.Tuple.$tc(,)
+      ((:) @ GHC.Types.KindRep
+         $krep ((:) @ GHC.Types.KindRep $krep [] @ GHC.Types.KindRep))
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      T8958.$tcMap
       ((:) @ GHC.Types.KindRep
-         (GHC.Types.KindRepVar 0) [] @ GHC.Types.KindRep)
+         $krep ((:) @ GHC.Types.KindRep $krep [] @ GHC.Types.KindRep))
+$krep [InlPrag=[~]] = GHC.Types.KindRepTYPE GHC.Types.LiftedRep
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      GHC.Types.$tc[]
+      ((:) @ GHC.Types.KindRep $krep [] @ GHC.Types.KindRep)
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      T8958.$tcRepresentational
+      ((:) @ GHC.Types.KindRep $krep [] @ GHC.Types.KindRep)
+$krep [InlPrag=[~]]
+  = GHC.Types.KindRepTyConApp
+      T8958.$tcNominal
+      ((:) @ GHC.Types.KindRep $krep [] @ GHC.Types.KindRep)
 T8958.$trModule
   = GHC.Types.Module
       (GHC.Types.TrNameS "main"#) (GHC.Types.TrNameS "T8958"#)