Address PR 118 review comments

angerman · angerman · commit 233a623755ae · 2025-12-02T12:36:39.000+09:00
This commit addresses all review comments from PR 118:

1. Fix HAVE_INTERPRETER vs HAVE_JS_BACKEND mismatch (Critical)
   - Split CPP guards: HAVE_INTERPRETER for bytecode/interpreter
   - Use HAVE_JS_BACKEND for StgToJS modules
   - Affected files: GHC/Driver/Main.hs, Pipeline.hs, Pipeline/Execute.hs

2. Clean up "MINIMAL build" references
   - Replace with explicit CPP flag references
   - e.g., "HAVE_INTERPRETER not defined" instead of "MINIMAL build"
   - Affected files: GHC.hs, Driver/Main.hs, Driver/Make.hs,
     Driver/Session/Inspect.hs, Driver/Pipeline/Execute.hs,
     Tc/Types.hs, Tc/Gen/Splice.hs

3. Refactor RegTarget to GADT-based approach
   - Introduce ArchKind data type for type-level architecture tags
   - Use GADT RegTarget with architecture-specific constructors
   - Add SomeRegTarget existential wrapper for runtime dispatch
   - Define RegOps typeclass with per-architecture instances
   - Add withRegTarget helper using rank-2 types
   - Add INLINE pragmas for performance
diff --git a/compiler/GHC.hs b/compiler/GHC.hs
@@ -826,7 +826,7 @@ setTopSessionDynFlags dflags = do
       return Nothing
 #endif
 #else
-  -- MINIMAL build: no interpreter support
+  -- No interpreter support (HAVE_INTERPRETER not defined)
   let interp = Nothing
 #endif
 
@@ -1181,7 +1181,7 @@ initialiseInteractiveDynFlags dflags hsc_env0 = do
                   }
               }
 #else
-  -- MINIMAL build: no plugin support, no IC modifications
+  -- No plugin support (HAVE_INTERPRETER not defined)
   return hsc_env0
 #endif
 
diff --git a/compiler/GHC/CmmToAsm/Reg/Target.hs b/compiler/GHC/CmmToAsm/Reg/Target.hs
diff --git a/compiler/GHC/Driver/Main.hs b/compiler/GHC/Driver/Main.hs
@@ -145,7 +145,7 @@ import GHC.Driver.Config.Stg.Pipeline (initStgPipelineOpts)
 import GHC.Driver.Config.StgToCmm  (initStgToCmmConfig)
 import GHC.Driver.Config.Cmm       (initCmmConfig)
 import GHC.Driver.LlvmConfigCache  (initLlvmConfigCache)
-#if defined(HAVE_INTERPRETER)
+#if defined(HAVE_JS_BACKEND)
 import GHC.Driver.Config.StgToJS  (initStgToJSConfig)
 #endif
 import GHC.Driver.Config.Diagnostic
@@ -176,6 +176,8 @@ import GHC.HsToCore
 
 #if defined(HAVE_INTERPRETER)
 import GHC.StgToByteCode    ( byteCodeGen )
+#endif
+#if defined(HAVE_JS_BACKEND)
 import GHC.StgToJS          ( stgToJS )
 import GHC.StgToJS.Ids
 import GHC.StgToJS.Types
@@ -326,15 +328,18 @@ import qualified GHC.Unit.Home.Graph as HUG
 import GHC.Unit.Home.PackageTable
 
 #if !defined(HAVE_INTERPRETER)
--- Stub implementations for MINIMAL build
+-- Stub when interpreter not available
 initializePlugins :: HscEnv -> IO HscEnv
 initializePlugins = return
+#endif
 
+#if !defined(HAVE_JS_BACKEND)
+-- Stub when JS backend not available
 initStgToJSConfig :: DynFlags -> StgToJSConfig
 initStgToJSConfig _ = StgToJSConfig  -- StgToJSConfig stub is from GHC.Runtime.Interpreter.Types
 
 stgToJS :: Logger -> StgToJSConfig -> [CgStgTopBinding] -> Module -> [SptEntry] -> ForeignStubs -> ([CostCentre], [CostCentreStack]) -> FilePath -> IO ()
-stgToJS _ _ _ _ _ _ _ _ = panic "stgToJS: not available in MINIMAL build"
+stgToJS _ _ _ _ _ _ _ _ = panic "stgToJS: not available (HAVE_JS_BACKEND not defined)"
 #endif
 
 {- **********************************************************************
@@ -1313,7 +1318,7 @@ hscDesugarAndSimplify summary (FrontendTypecheck tc_result) tc_warnings mb_old_h
       -- Just cause we desugared doesn't mean we are generating code, see above.
       Just desugared_guts | backendGeneratesCode bcknd -> do
 #if !defined(HAVE_INTERPRETER)
-          -- In MINIMAL builds, no TH plugins can be registered
+          -- No TH plugins can be registered (HAVE_INTERPRETER not defined)
           let plugins = []
 #else
           plugins <- liftIO $ readIORef (tcg_th_coreplugins tc_result)
@@ -1341,7 +1346,7 @@ hscDesugarAndSimplify summary (FrontendTypecheck tc_result) tc_warnings mb_old_h
           -- in order to inline data con wrappers but we honour whatever level of simplificication the
           -- user requested. See #22008 for some discussion.
 #if !defined(HAVE_INTERPRETER)
-          -- In MINIMAL builds, no TH plugins can be registered
+          -- No TH plugins can be registered (HAVE_INTERPRETER not defined)
           let plugins = []
 #else
           plugins <- liftIO $ readIORef (tcg_th_coreplugins tc_result)
diff --git a/compiler/GHC/Driver/Make.hs b/compiler/GHC/Driver/Make.hs
@@ -1266,7 +1266,7 @@ addSptEntries hsc_env mlinkable =
      , spt <- bc_spt_entries bco
      ]
 #else
-addSptEntries _ _ = return ()  -- No bytecode support in MINIMAL build
+addSptEntries _ _ = return ()  -- No bytecode support (HAVE_INTERPRETER not defined)
 #endif
 
 
diff --git a/compiler/GHC/Driver/Pipeline.hs b/compiler/GHC/Driver/Pipeline.hs
@@ -78,7 +78,7 @@ import GHC.Linker.Static
 import GHC.Linker.Static.Utils
 import GHC.Linker.Types
 
-#if defined(HAVE_INTERPRETER)
+#if defined(HAVE_JS_BACKEND)
 import GHC.Driver.Config.StgToJS
 import GHC.StgToJS.Linker.Linker
 #endif
diff --git a/compiler/GHC/Driver/Pipeline/Execute.hs b/compiler/GHC/Driver/Pipeline/Execute.hs
@@ -79,7 +79,7 @@ import GHC.Unit.Module.Env
 import GHC.Driver.Env.KnotVars
 import GHC.Driver.Config.Finder
 import GHC.Rename.Names
-#if defined(HAVE_INTERPRETER)
+#if defined(HAVE_JS_BACKEND)
 import GHC.StgToJS.Linker.Linker (embedJsFile)
 #endif
 
@@ -635,7 +635,7 @@ runHscBackendPhase pipe_env hsc_env mod_name src_flavour location result = do
               bc <- generateFreshByteCode hsc_env mod_name (mkCgInteractiveGuts cgguts) mod_location
               return ([], final_iface, emptyHomeModInfoLinkable { homeMod_bytecode = Just bc } , panic "interpreter")
 #else
-            panic "GHC.Driver.Pipeline.Execute.runHscPhase: bytecode generation not supported in MINIMAL build"
+            panic "GHC.Driver.Pipeline.Execute.runHscPhase: bytecode generation not supported (HAVE_INTERPRETER not defined)"
 #endif
 
 
diff --git a/compiler/GHC/Driver/Session/Inspect.hs b/compiler/GHC/Driver/Session/Inspect.hs
@@ -44,7 +44,7 @@ import GHC.Utils.Outputable
 import qualified GHC.Unit.Home.Graph as HUG
 
 #if !defined(HAVE_INTERPRETER)
--- Stub type for MINIMAL build (replaces GHC.ByteCode.Breakpoints.InternalModBreaks)
+-- Stub type when interpreter is not available (replaces GHC.ByteCode.Breakpoints.InternalModBreaks)
 data InternalModBreaks = InternalModBreaks
 #endif
 
@@ -164,7 +164,7 @@ getHomeModuleInfo hsc_env mdl =
 #if defined(HAVE_INTERPRETER)
                         minf_modBreaks = getModBreaks hmi
 #else
-                        minf_modBreaks = Nothing  -- No bytecode support in MINIMAL build
+                        minf_modBreaks = Nothing  -- No bytecode support (HAVE_INTERPRETER not defined)
 #endif
                         }))
 
diff --git a/compiler/GHC/Tc/Gen/Splice.hs b/compiler/GHC/Tc/Gen/Splice.hs
@@ -1969,32 +1969,32 @@ getAnnotationsByTypeRep th_name tyrep
        ; let selectedTcgAnns = findAnnsByTypeRep (tcg_ann_env tcg) name tyrep
        ; return (selectedEpsHptAnns ++ selectedTcgAnns) }
 #else
--- MINIMAL build: Template Haskell execution not supported
+-- Template Haskell execution not supported (HAVE_INTERPRETER not defined)
 -- Provide stub implementations that error at runtime for functions called from unguarded code
 
 runMetaE :: LHsExpr GhcTc -> TcM (LHsExpr GhcPs)
-runMetaE _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runMetaE _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 runMetaP :: LHsExpr GhcTc -> TcM (LPat GhcPs)
-runMetaP _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runMetaP _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 runMetaT :: LHsExpr GhcTc -> TcM (LHsType GhcPs)
-runMetaT _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runMetaT _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 runMetaD :: LHsExpr GhcTc -> TcM [LHsDecl GhcPs]
-runMetaD _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runMetaD _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 runMetaAW :: LHsExpr GhcTc -> TcM Serialized
-runMetaAW _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runMetaAW _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 runTH :: THResultType -> ForeignHValue -> TcM a
-runTH _ _ = fail "Template Haskell execution is not supported in MINIMAL build"
+runTH _ _ = fail "Template Haskell execution is not supported (HAVE_INTERPRETER not defined)"
 
 finishTH :: TcM ()
-finishTH = return ()  -- Nothing to finish in MINIMAL build
+finishTH = return ()  -- Nothing to finish (HAVE_INTERPRETER not defined)
 
 runRemoteModFinalizers :: ThModFinalizers -> TcM ()
-runRemoteModFinalizers _ = fail "Template Haskell mod finalizers not supported in MINIMAL build"
+runRemoteModFinalizers _ = fail "Template Haskell mod finalizers not supported (HAVE_INTERPRETER not defined)"
 #endif
 
 {-
diff --git a/compiler/GHC/Tc/Types.hs b/compiler/GHC/Tc/Types.hs
@@ -195,7 +195,7 @@ import Data.Typeable ( TypeRep )
 import Data.Maybe    ( mapMaybe )
 
 #if !defined(HAVE_INTERPRETER)
--- Stub types for MINIMAL build (no ghci dependency)
+-- Stub types when interpreter is not available (no ghci dependency)
 data QState = QState  -- Stub for Template Haskell state
 #endif
 

Original file line number	Diff line number	Diff line change
`@@ -1266,7 +1266,7 @@ addSptEntries hsc_env mlinkable =`
`1266`	`1266`	`, spt <- bc_spt_entries bco`
`1267`	`1267`	`]`
`1268`	`1268`	`#else`
`1269`		`-addSptEntries _ _ = return () -- No bytecode support in MINIMAL build`
	`1269`	`+addSptEntries _ _ = return () -- No bytecode support (HAVE_INTERPRETER not defined)`
`1270`	`1270`	`#endif`
`1271`	`1271`
`1272`	`1272`