work on more sophisticated IR location design

Author: csabahruska

external-stg/lib/Stg/IRLocation.hs

@@ -4,10 +4,107 @@ import Stg.Syntax
 
 data StgPoint
   -- expression locations
-  = SP_CaseScrutineeExpr  { spScrutineeResultName :: Name }
+  = SP_CaseScrutineeExpr  { spScrutineeResultName :: Id }
   | SP_LetExpr            { spParent :: StgPoint }
   | SP_LetNoEscapeExpr    { spParent :: StgPoint }
-  | SP_RhsClosureExpr     { spRhsBinderName :: Name }
-  | SP_AltExpr            { spScrutineeResultName :: Name, spAltIndex :: Int }
-  | SP_RhsCon             { spRhsBinderName :: Name }
+  | SP_RhsClosureExpr     { spRhsBinderName :: Id }
+  | SP_AltExpr            { spScrutineeResultName :: Id, spAltIndex :: Int }
+  | SP_RhsCon             { spRhsBinderName :: Id }
   deriving (Eq, Ord, Show)
+
+{-
+  breakpoint types:
+    - program point: IRPath
+    - primop name
+    - foreign symbol name
+-}
+
+{-
+  unitid        - name
+  Module        - name
+   topbinding   - name
+    binding     - name
+     rhs
+      arg
+      expr
+       arg
+       expr
+       binding
+       alt
+        expr
+-}
+{-
+  identification methods:
+    - unique name
+    - index (this means the parent's children index, e.g. Case's Alt chidren)
+-}
+{-
+  StgPoint location root:
+    - top IR data structure: [Module]
+    - uniqueNamed
+        TopBinding
+        Binding (StgNonRec binding)
+        Rhs (StgRec binding)
+        Expr (StgCase)
+-}
+{-
+  IR elements with unique names:
+    - StgCase
+    - StgNonRec
+    - any Rhs ; from StgRec
+    - StgTopStringLit
+-}
+
+-- can select any type that StgIR can represent
+data FieldSelector
+  -- generic
+  = FS_UniqueName                 Name  -- selects uniquely named IR element
+  | FS_Binder                     Id    -- selects uniquely named IR element
+
+  -- Module
+  | FS_Module_moduleTopBindings   Int   -- selects: Module     -> TopBinding
+  -- TopBinding
+  | FS_StgTopLifted_arg0                -- selects: TopBinding -> Binding
+  -- Binding
+  | FS_StgNonRec_arg0                   -- selects: Binding    -> Rhs
+  | FS_StgRec_arg0                Int   -- selects: Binding    -> Rhs
+  -- Rhs
+  | FS_StgRhsClosure_arg0         Int   -- selects: Rhs        -> Binder
+  | FS_StgRhsClosure_arg2         Int   -- selects: Rhs        -> Binder
+  | FS_StgRhsClosure_arg3               -- selects: Rhs        -> Expr
+  | FS_StgRhsCon_arg1             Int   -- selects: Rhs        -> Arg
+  -- Arg
+  | FS_StgVarArg_arg0                   -- selects: Arg        -> Binder
+  -- Expr
+  | FS_StgApp_arg0                      -- selects: Expr       -> Binder
+  | FS_StgApp_arg1                Int   -- selects: Expr       -> Arg
+  | FS_StgConApp_arg1             Int   -- selects: Expr       -> Arg
+  | FS_StgOpApp_arg1              Int   -- selects: Expr       -> Arg
+  | FS_StgCase_arg0                     -- selects: Expr       -> Expr
+  | FS_StgCase_arg1                     -- selects: Expr       -> Binder
+  | FS_StgCase_arg3               Int   -- selects: Expr       -> Alt
+  | FS_StgLet_arg0                      -- selects: Expr       -> Binding
+  | FS_StgLet_arg1                      -- selects: Expr       -> Expr
+  | FS_StgLetNoEscape_arg0              -- selects: Expr       -> Binding
+  | FS_StgLetNoEscape_arg1              -- selects: Expr       -> Expr
+  | FS_StgTick_arg0                     -- selects: Expr       -> Expr
+  -- Alt
+  | FS_Alt_altBinders             Int   -- selects: Alt        -> Binder
+  | FS_Alt_altRHS                       -- selects: Alt        -> Expr
+  deriving (Eq, Ord, Show)
+
+type IRPath = [FieldSelector]
+
+data IR
+  = IR_Module     Module
+  | IR_TopBinding TopBinding
+  | IR_Binding    Binding
+  | IR_Rhs        Rhs
+  | IR_Arg        Arg
+  | IR_Expr       Expr
+  | IR_Alt        Alt
+  | IR_Binder     Binder
+  deriving (Eq, Ord, Show)
+
+lookupIR :: IR -> IRPath -> IR
+lookupIR = undefined