Merge pull request #2599 from clash-lang/fix2598

flattenLet applied in bottomup traversal

Author: christiaanb

benchmark/clash-benchmark.cabal

@@ -26,6 +26,9 @@ library
                        clash-lib,
                        clash-prelude
 
+  if impl(ghc >= 9.0.0)
+    build-depends:     ghc-boot
+
 executable clash-benchmark-normalization
   main-is:             benchmark-normalization.hs
   default-language:    Haskell2010

benchmark/common/BenchmarkCommon.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE TypeApplications #-}
 
 module BenchmarkCommon where
@@ -17,6 +18,22 @@ import Clash.GHC.NetlistTypes
 
 import qualified Control.Concurrent.Supply as Supply
 
+#if MIN_VERSION_ghc(9,2,0)
+import qualified GHC.Driver.Monad as GHC
+import qualified GHC.Driver.Session as GHC
+import qualified GHC.Driver.Env.Types as GHC
+import qualified GHC.LanguageExtensions as LangExt
+import qualified GHC.Settings as GHC
+import qualified GHC.Utils.Fingerprint as GHC
+#elif MIN_VERSION_ghc(9,0,0)
+import qualified GHC.Driver.Monad as GHC
+import qualified GHC.Driver.Session as GHC
+import qualified GHC.Driver.Types as GHC
+import qualified GHC.LanguageExtensions as LangExt
+import qualified GHC.Settings as GHC
+import qualified GHC.Utils.Fingerprint as GHC
+#endif
+
 defaultTests :: [FilePath]
 defaultTests =
   [ "examples/FIR.hs"
@@ -49,7 +66,34 @@ runInputStage idirs src = do
   let o = opts idirs
   let backend = initBackend @VHDLState o
   pds <- primDirs backend
-  generateBindings o (return ()) pds (opt_importPaths o) [] (hdlKind backend) src Nothing
+  generateBindings o action pds (opt_importPaths o) [] (hdlKind backend) src Nothing
+ where
+#if MIN_VERSION_ghc(9,0,0)
+  action = do
+    env <- GHC.getSession
+    let df0 = GHC.hsc_dflags env
+#if MIN_VERSION_ghc(9,4,0)
+        df1 = addOptP "-DCLASH_OPAQUE=OPAQUE" df0
+#else
+        df1 = addOptP "-DCLASH_OPAQUE=NOINLINE" df0
+#endif
+        df2 = GHC.xopt_set df1 LangExt.Cpp
+    GHC.setSession (env {GHC.hsc_dflags = df2})
+
+  addOptP :: String -> GHC.DynFlags -> GHC.DynFlags
+  addOptP   f = alterToolSettings $ \s -> s
+            { GHC.toolSettings_opt_P   = f : GHC.toolSettings_opt_P s
+            , GHC.toolSettings_opt_P_fingerprint = fingerprintStrings (f : GHC.toolSettings_opt_P s)
+            }
+
+  alterToolSettings :: (GHC.ToolSettings -> GHC.ToolSettings) -> GHC.DynFlags -> GHC.DynFlags
+  alterToolSettings f dynFlags = dynFlags { GHC.toolSettings = f (GHC.toolSettings dynFlags) }
+
+  fingerprintStrings :: [String] -> GHC.Fingerprint
+  fingerprintStrings ss = GHC.fingerprintFingerprints $ map GHC.fingerprintString ss
+#else
+  action = return ()
+#endif
 
 runNormalisationStage
   :: [FilePath]

changelog/2023-11-06T14_40_14+01_00_fix_2598

@@ -0,0 +1 @@
+FIXED: Name duplication in generated Verilog involving reset synchronizer [#2598](https://github.com/clash-lang/clash-compiler/issues/2598)

clash-lib/src/Clash/Normalize.hs

@@ -2,7 +2,7 @@
   Copyright   :  (C) 2012-2016, University of Twente,
                      2016     , Myrtle Software Ltd,
                      2017     , Google Inc.,
-                     2021-2022, QBayLogic B.V.
+                     2021-2023, QBayLogic B.V.
   License     :  BSD2 (see the file LICENSE)
   Maintainer  :  QBayLogic B.V. <[email protected]>
 
@@ -71,7 +71,8 @@ import           Clash.Normalize.Strategy
 import           Clash.Normalize.Transformations
 import           Clash.Normalize.Types
 import           Clash.Normalize.Util
-import           Clash.Rewrite.Combinators        ((>->),(!->),repeatR,topdownR)
+import           Clash.Rewrite.Combinators
+  ((>->), (!->), bottomupR, repeatR, topdownR)
 import           Clash.Rewrite.Types
   (RewriteEnv (..), RewriteState (..), bindings, debugOpts, extra,
    tcCache, topEntities, newInlineStrategy)
@@ -378,8 +379,8 @@ flattenCallTree (CBranch (nm,(Binding nm' sp inl pr tm r)) used) = do
                  apply "caseCon" caseCon >->
                  (apply "reduceConst" reduceConst !-> apply "deadcode" deadCode) >->
                  apply "reduceNonRepPrim" reduceNonRepPrim >->
-                 apply "removeUnusedExpr" removeUnusedExpr >->
-                 apply "flattenLet" flattenLet)) !->
+                 apply "removeUnusedExpr" removeUnusedExpr) >->
+               bottomupR (apply "flattenLet" flattenLet)) !->
       topdownSucR (apply "topLet" topLet)
 
     goCheap c@(CLeaf   (nm2,(Binding _ _ inl2 _ e _)))