Add VecSlot for unboxed sums of SIMD vectors

This patch adds the missing `VecRep` case to `primRepSlot` function and
all the necessary machinery to carry this new `VecSlot` through code
generation. This allows programs involving unboxed sums of SIMD vectors
to be written and compiled.

Fixes #22187

4 files changed, 10 insertions, 4 deletions

diff --git a/compiler/GHC/Cmm/Utils.hs b/compiler/GHC/Cmm/Utils.hs
index 3671366d07..7524ba7c5e 100644
--- a/compiler/GHC/Cmm/Utils.hs
+++ b/compiler/GHC/Cmm/Utils.hs
@@ -113,7 +113,7 @@ primRepCmmType platform = \case
    AddrRep          -> bWord platform
    FloatRep         -> f32
    DoubleRep        -> f64
-   (VecRep len rep) -> vec len (primElemRepCmmType rep)
+   VecRep len rep   -> vec len (primElemRepCmmType rep)
 
 slotCmmType :: Platform -> SlotTy -> CmmType
 slotCmmType platform = \case
@@ -123,6 +123,7 @@ slotCmmType platform = \case
    Word64Slot      -> b64
    FloatSlot       -> f32
    DoubleSlot      -> f64
+   VecSlot l e     -> vec l (primElemRepCmmType e)
 
 primElemRepCmmType :: PrimElemRep -> CmmType
 primElemRepCmmType Int8ElemRep   = b8
diff --git a/compiler/GHC/Stg/Unarise.hs b/compiler/GHC/Stg/Unarise.hs
index 440b184d44..8dfdeb607c 100644
--- a/compiler/GHC/Stg/Unarise.hs
+++ b/compiler/GHC/Stg/Unarise.hs
@@ -694,6 +694,8 @@ ubxSumRubbishArg WordSlot   = StgLitArg (LitNumber LitNumWord 0)
 ubxSumRubbishArg Word64Slot = StgLitArg (LitNumber LitNumWord64 0)
 ubxSumRubbishArg FloatSlot  = StgLitArg (LitFloat 0)
 ubxSumRubbishArg DoubleSlot = StgLitArg (LitDouble 0)
+ubxSumRubbishArg (VecSlot n e) = StgLitArg (LitRubbish vec_rep)
+  where vec_rep = primRepToRuntimeRep (VecRep n e)
 
 --------------------------------------------------------------------------------
 
diff --git a/compiler/GHC/Types/Literal.hs b/compiler/GHC/Types/Literal.hs
index 199d744034..9997859afc 100644
--- a/compiler/GHC/Types/Literal.hs
+++ b/compiler/GHC/Types/Literal.hs
@@ -67,6 +67,7 @@ module GHC.Types.Literal
 import GHC.Prelude
 
 import GHC.Builtin.Types.Prim
+import GHC.Core.TyCo.Rep ( RuntimeRepType )
 import GHC.Core.Type
 import GHC.Utils.Outputable
 import GHC.Data.FastString
@@ -131,7 +132,7 @@ data Literal
                                 -- that can be represented as a Literal. Create
                                 -- with 'nullAddrLit'
 
-  | LitRubbish Type             -- ^ A nonsense value of the given
+  | LitRubbish RuntimeRepType   -- ^ A nonsense value of the given
                                 -- representation. See Note [Rubbish literals].
                                 --
                                 -- The Type argument, rr, is of kind RuntimeRep.
diff --git a/compiler/GHC/Types/RepType.hs b/compiler/GHC/Types/RepType.hs
index 993694e1c3..30eb12c7a7 100644
--- a/compiler/GHC/Types/RepType.hs
+++ b/compiler/GHC/Types/RepType.hs
@@ -286,7 +286,7 @@ layoutUbxSum sum_slots0 arg_slots0 =
 --
 -- TODO(michalt): We should probably introduce `SlotTy`s for 8-/16-/32-bit
 -- values, so that we can pack things more tightly.
-data SlotTy = PtrLiftedSlot | PtrUnliftedSlot | WordSlot | Word64Slot | FloatSlot | DoubleSlot
+data SlotTy = PtrLiftedSlot | PtrUnliftedSlot | WordSlot | Word64Slot | FloatSlot | DoubleSlot | VecSlot Int PrimElemRep
   deriving (Eq, Ord)
     -- Constructor order is important! If slot A could fit into slot B
     -- then slot A must occur first.  E.g.  FloatSlot before DoubleSlot
@@ -301,6 +301,7 @@ instance Outputable SlotTy where
   ppr WordSlot        = text "WordSlot"
   ppr DoubleSlot      = text "DoubleSlot"
   ppr FloatSlot       = text "FloatSlot"
+  ppr (VecSlot n e)   = text "VecSlot" <+> ppr n <+> ppr e
 
 typeSlotTy :: UnaryType -> Maybe SlotTy
 typeSlotTy ty
@@ -326,7 +327,7 @@ primRepSlot Word64Rep   = Word64Slot
 primRepSlot AddrRep     = WordSlot
 primRepSlot FloatRep    = FloatSlot
 primRepSlot DoubleRep   = DoubleSlot
-primRepSlot VecRep{}    = pprPanic "primRepSlot" (text "No slot for VecRep")
+primRepSlot (VecRep n e) = VecSlot n e
 
 slotPrimRep :: SlotTy -> PrimRep
 slotPrimRep PtrLiftedSlot   = LiftedRep
@@ -335,6 +336,7 @@ slotPrimRep Word64Slot      = Word64Rep
 slotPrimRep WordSlot        = WordRep
 slotPrimRep DoubleSlot      = DoubleRep
 slotPrimRep FloatSlot       = FloatRep
+slotPrimRep (VecSlot n e)   = VecRep n e
 
 -- | Returns the bigger type if one fits into the other. (commutative)
 --