Handle Char#, Addr# in TH quasiquoter (fixes #10620)

DsMeta does not attempt to handle quasiquoted Char# or Addr# values,
which causes expressions like `$([| 'a'# |])` or `$([| "abc"# |])` to
fail
with an `Exotic literal not (yet) handled by Template Haskell` error.

To fix this, the API of `template-haskell` had to be changed so that
`Lit`
now has an extra constructor `CharPrimL` (a `StringPrimL` constructor
already
existed, but it wasn't used). In addition, `DsMeta` has to manipulate
`CoreExpr`s directly that involve `Word8`s. In order to do this,
`Word8` had
to be added as a wired-in type to `TysWiredIn`.

Actually converting from `HsCharPrim` and `HsStringPrim` to `CharPrimL`
and
`StringPrimL`, respectively, is pretty straightforward after that, since
both `HsCharPrim` and `CharPrimL` use `Char` internally, and
`HsStringPrim`
uses a `ByteString` internally, which can easily be converted to
`[Word8]`,
which is what `StringPrimL` uses.

Reviewers: goldfire, austin, simonpj, bgamari

Reviewed By: simonpj, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1054

GHC Trac Issues: #10620

3 files changed, 35 insertions, 9 deletions

diff --git a/compiler/prelude/PrelNames.hs b/compiler/prelude/PrelNames.hs
index 570ec071b0..32c133d924 100644
--- a/compiler/prelude/PrelNames.hs
+++ b/compiler/prelude/PrelNames.hs
@@ -282,7 +282,7 @@ basicKnownKeyNames
         -- FFI primitive types that are not wired-in.
         stablePtrTyConName, ptrTyConName, funPtrTyConName,
         int8TyConName, int16TyConName, int32TyConName, int64TyConName,
-        word8TyConName, word16TyConName, word32TyConName, word64TyConName,
+        word16TyConName, word32TyConName, word64TyConName,
 
         -- Others
         otherwiseIdName, inlineIdName,
@@ -1117,8 +1117,7 @@ int32TyConName    = tcQual gHC_INT  (fsLit "Int32") int32TyConKey
 int64TyConName    = tcQual gHC_INT  (fsLit "Int64") int64TyConKey
 
 -- Word module
-word8TyConName, word16TyConName, word32TyConName, word64TyConName :: Name
-word8TyConName    = tcQual  gHC_WORD (fsLit "Word8")  word8TyConKey
+word16TyConName, word32TyConName, word64TyConName :: Name
 word16TyConName   = tcQual  gHC_WORD (fsLit "Word16") word16TyConKey
 word32TyConName   = tcQual  gHC_WORD (fsLit "Word32") word32TyConKey
 word64TyConName   = tcQual  gHC_WORD (fsLit "Word64") word64TyConKey
@@ -1567,7 +1566,8 @@ typeRepTyConKey = mkPreludeTyConUnique 183
 charDataConKey, consDataConKey, doubleDataConKey, falseDataConKey,
     floatDataConKey, intDataConKey, integerSDataConKey, nilDataConKey,
     ratioDataConKey, stableNameDataConKey, trueDataConKey, wordDataConKey,
-    ioDataConKey, integerDataConKey, eqBoxDataConKey, coercibleDataConKey :: Unique
+    word8DataConKey, ioDataConKey, integerDataConKey, eqBoxDataConKey,
+    coercibleDataConKey :: Unique
 charDataConKey                          = mkPreludeDataConUnique  1
 consDataConKey                          = mkPreludeDataConUnique  2
 doubleDataConKey                        = mkPreludeDataConUnique  3
@@ -1577,6 +1577,7 @@ intDataConKey                           = mkPreludeDataConUnique  6
 integerSDataConKey                      = mkPreludeDataConUnique  7
 nilDataConKey                           = mkPreludeDataConUnique 11
 ratioDataConKey                         = mkPreludeDataConUnique 12
+word8DataConKey                         = mkPreludeDataConUnique 13
 stableNameDataConKey                    = mkPreludeDataConUnique 14
 trueDataConKey                          = mkPreludeDataConUnique 15
 wordDataConKey                          = mkPreludeDataConUnique 16
diff --git a/compiler/prelude/THNames.hs b/compiler/prelude/THNames.hs
index 5ccfaeb3e8..254431e360 100644
--- a/compiler/prelude/THNames.hs
+++ b/compiler/prelude/THNames.hs
@@ -33,7 +33,8 @@ templateHaskellNames = [
 
     -- Lit
     charLName, stringLName, integerLName, intPrimLName, wordPrimLName,
-    floatPrimLName, doublePrimLName, rationalLName,
+    floatPrimLName, doublePrimLName, rationalLName, stringPrimLName,
+    charPrimLName,
     -- Pat
     litPName, varPName, tupPName, unboxedTupPName,
     conPName, tildePName, bangPName, infixPName,
@@ -188,7 +189,8 @@ unsafeTExpCoerceName = thFun (fsLit "unsafeTExpCoerce") unsafeTExpCoerceIdKey
 -------------------- TH.Lib -----------------------
 -- data Lit = ...
 charLName, stringLName, integerLName, intPrimLName, wordPrimLName,
-    floatPrimLName, doublePrimLName, rationalLName :: Name
+    floatPrimLName, doublePrimLName, rationalLName, stringPrimLName,
+    charPrimLName :: Name
 charLName       = libFun (fsLit "charL")       charLIdKey
 stringLName     = libFun (fsLit "stringL")     stringLIdKey
 integerLName    = libFun (fsLit "integerL")    integerLIdKey
@@ -197,6 +199,8 @@ wordPrimLName   = libFun (fsLit "wordPrimL")   wordPrimLIdKey
 floatPrimLName  = libFun (fsLit "floatPrimL")  floatPrimLIdKey
 doublePrimLName = libFun (fsLit "doublePrimL") doublePrimLIdKey
 rationalLName   = libFun (fsLit "rationalL")     rationalLIdKey
+stringPrimLName = libFun (fsLit "stringPrimL") stringPrimLIdKey
+charPrimLName   = libFun (fsLit "charPrimL")   charPrimLIdKey
 
 -- data Pat = ...
 litPName, varPName, tupPName, unboxedTupPName, conPName, infixPName, tildePName, bangPName,
@@ -556,7 +560,8 @@ unsafeTExpCoerceIdKey = mkPreludeMiscIdUnique 212
 
 -- data Lit = ...
 charLIdKey, stringLIdKey, integerLIdKey, intPrimLIdKey, wordPrimLIdKey,
-    floatPrimLIdKey, doublePrimLIdKey, rationalLIdKey :: Unique
+    floatPrimLIdKey, doublePrimLIdKey, rationalLIdKey, stringPrimLIdKey,
+    charPrimLIdKey:: Unique
 charLIdKey        = mkPreludeMiscIdUnique 220
 stringLIdKey      = mkPreludeMiscIdUnique 221
 integerLIdKey     = mkPreludeMiscIdUnique 222
@@ -565,9 +570,11 @@ wordPrimLIdKey    = mkPreludeMiscIdUnique 224
 floatPrimLIdKey   = mkPreludeMiscIdUnique 225
 doublePrimLIdKey  = mkPreludeMiscIdUnique 226
 rationalLIdKey    = mkPreludeMiscIdUnique 227
+stringPrimLIdKey  = mkPreludeMiscIdUnique 228
+charPrimLIdKey    = mkPreludeMiscIdUnique 229
 
 liftStringIdKey :: Unique
-liftStringIdKey     = mkPreludeMiscIdUnique 228
+liftStringIdKey     = mkPreludeMiscIdUnique 230
 
 -- data Pat = ...
 litPIdKey, varPIdKey, tupPIdKey, unboxedTupPIdKey, conPIdKey, infixPIdKey, tildePIdKey, bangPIdKey,
diff --git a/compiler/prelude/TysWiredIn.hs b/compiler/prelude/TysWiredIn.hs
index 5ab8654f06..f7d08ff1c4 100644
--- a/compiler/prelude/TysWiredIn.hs
+++ b/compiler/prelude/TysWiredIn.hs
@@ -42,6 +42,9 @@ module TysWiredIn (
         -- * Word
         wordTyCon, wordDataCon, wordTyConName, wordTy,
 
+        -- * Word8
+        word8TyCon, word8DataCon, word8TyConName, word8Ty,
+
         -- * List
         listTyCon, listTyCon_RDR, listTyConName, listTyConKey,
         nilDataCon, nilDataConName, nilDataConKey,
@@ -152,6 +155,7 @@ wiredInTyCons = [ unitTyCon     -- Not treated like other tuples, because
               , floatTyCon
               , intTyCon
               , wordTyCon
+              , word8TyCon
               , listTyCon
               , parrTyCon
               , eqTyCon
@@ -198,9 +202,13 @@ listTyConName     = mkWiredInTyConName   BuiltInSyntax gHC_TYPES (fsLit "[]") li
 nilDataConName    = mkWiredInDataConName BuiltInSyntax gHC_TYPES (fsLit "[]") nilDataConKey nilDataCon
 consDataConName   = mkWiredInDataConName BuiltInSyntax gHC_TYPES (fsLit ":") consDataConKey consDataCon
 
-wordTyConName, wordDataConName, floatTyConName, floatDataConName, doubleTyConName, doubleDataConName :: Name
+wordTyConName, wordDataConName, word8TyConName, word8DataConName :: Name
 wordTyConName      = mkWiredInTyConName   UserSyntax gHC_TYPES (fsLit "Word")   wordTyConKey     wordTyCon
 wordDataConName    = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "W#")     wordDataConKey   wordDataCon
+word8TyConName     = mkWiredInTyConName   UserSyntax gHC_WORD  (fsLit "Word8")  word8TyConKey    word8TyCon
+word8DataConName   = mkWiredInDataConName UserSyntax gHC_WORD  (fsLit "W8#")    word8DataConKey  word8DataCon
+
+floatTyConName, floatDataConName, doubleTyConName, doubleDataConName :: Name
 floatTyConName     = mkWiredInTyConName   UserSyntax gHC_TYPES (fsLit "Float")  floatTyConKey    floatTyCon
 floatDataConName   = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "F#")     floatDataConKey  floatDataCon
 doubleTyConName    = mkWiredInTyConName   UserSyntax gHC_TYPES (fsLit "Double") doubleTyConKey   doubleTyCon
@@ -617,6 +625,16 @@ wordTyCon = pcNonRecDataTyCon wordTyConName
 wordDataCon :: DataCon
 wordDataCon = pcDataCon wordDataConName [] [wordPrimTy] wordTyCon
 
+word8Ty :: Type
+word8Ty = mkTyConTy word8TyCon
+
+word8TyCon :: TyCon
+word8TyCon = pcNonRecDataTyCon word8TyConName
+                      (Just (CType "" Nothing ("HsWord8", fsLit "HsWord8"))) []
+                      [word8DataCon]
+word8DataCon :: DataCon
+word8DataCon = pcDataCon word8DataConName [] [wordPrimTy] word8TyCon
+
 floatTy :: Type
 floatTy = mkTyConTy floatTyCon