Add offset information to some AST elements.wip

1 files changed, 21 insertions, 2 deletions

diff --git a/src/Language/Fiddle/Ast/Internal/SyntaxTree.hs b/src/Language/Fiddle/Ast/Internal/SyntaxTree.hs
index 73c4303..1e9ace7 100644
--- a/src/Language/Fiddle/Ast/Internal/SyntaxTree.hs
+++ b/src/Language/Fiddle/Ast/Internal/SyntaxTree.hs
@@ -13,6 +13,8 @@ module Language.Fiddle.Ast.Internal.SyntaxTree
     FiddleUnitInterface,
     QualificationMetadata,
     CommonQualificationData (..),
+    RegisterOffset,
+    BitsOffset,
     -- Witness Types
     Witness (..),
     WitnessType,
@@ -59,6 +61,7 @@ import Data.Text (Text)
 import Data.Type.Bool
 import Data.Typeable
 import Data.Void (Void)
+import Data.Word (Word32)
 import GHC.Generics
 import Language.Fiddle.Ast.Internal.Instances
 import Language.Fiddle.Ast.Internal.Kinds
@@ -73,6 +76,16 @@ newtype CommonQualificationData
   }
   deriving (Eq, Ord, Show)
 
+type BitsOffset stage = RegisterOffset stage
+
+-- | Type used for the RegisterOffset type. This is populated in the check
+-- stage, which will attach the appropriate offset to the register. This helps
+-- backends so they don't have to recalculate this offset.
+type family RegisterOffset stage where
+  RegisterOffset stage = If (stage < Checked) () Word32
+
+-- | Type which stores metadata after qualification. Before qualification, this
+-- metadata has not been calculated and so is unset.
 type family QualificationMetadata stage t where
   QualificationMetadata stage t =
     If (stage < Qualified) () t
@@ -470,7 +483,10 @@ data ObjTypeDecl stage f a where
     ObjTypeDecl stage f a
   -- | A register declaration.
   RegisterDecl ::
-    { -- | Optional register modifier.
+    { -- | Offset within the register. Calculated during the consistency check.
+      -- The offset is calculated from the top-level structure.
+      regOffset :: RegisterOffset stage,
+      -- | Optional register modifier.
       regModifier :: Maybe (Modifier f a),
       -- | Optional register identifier.
       regIdent :: Maybe (Identifier f a),
@@ -569,7 +585,10 @@ data RegisterBitsDecl stage f a where
     RegisterBitsDecl stage f a
   -- | Declaration for defined bits in a register.
   DefinedBits ::
-    { -- | Optional modifier for the bits.
+    { -- | The offset for these bits. This is calculated during the
+      -- ConsistencyCheck phase, so until this phase it's just ().
+      definedBitsOffset :: BitsOffset stage,
+      -- | Optional modifier for the bits.
       definedBitsModifier :: Maybe (Modifier f a),
       -- | Identifier for the bits.
       definedBitsIdent :: Identifier f a,