pass through support for DPI imports and exports

CHANGELOG.md

@@ -5,6 +5,7 @@
 * Added support for excluding the conversion of unbased unsized literals (e.g.,
   `'1`, `'x`) via `--exclude UnbasedUniszed`
 * Added support for enumerated type ranges (e.g., `enum { X[3:5] }`)
+* Added support for passing through DPI imports and exports
 
 ### Other Enhancements
 

src/Convert/Package.hs

@@ -778,6 +778,8 @@ piNames (Decl (Net  _ _ _ _ ident _ _)) = [ident]
 piNames (Decl (Param    _ _ ident   _)) = [ident]
 piNames (Decl (ParamType  _ ident   _)) = [ident]
 piNames (Decl (CommentDecl          _)) = []
-piNames (Import x y) = [show $ Import x y]
-piNames (Export x y) = [show $ Export x y]
+piNames item@DPIImport{} = [show item]
+piNames item@DPIExport{} = [show item]
+piNames item@Import{} = [show item]
+piNames item@Export{} = [show item]
 piNames (Directive _) = []

src/Convert/RemoveComments.hs

@@ -39,6 +39,9 @@ convertPackageItem (Task     l   x decls stmts) =
     where
         decls' = convertDecls decls
         stmts' = convertStmts stmts
+convertPackageItem (DPIImport spec prop alias typ name decls) =
+    DPIImport spec prop alias typ name decls'
+    where decls' = convertDecls decls
 convertPackageItem other = other
 
 convertStmt :: Stmt -> Stmt

src/Convert/Scoper.hs

@@ -561,6 +561,14 @@ scopeModuleItem declMapperRaw moduleItemMapper genItemMapper stmtMapperRaw =
             return $ MIPackageItem $ Task ml x' decls' stmts'
         fullModuleItemMapper (MIPackageItem (Decl decl)) =
             declMapper decl >>= return . MIPackageItem . Decl
+        fullModuleItemMapper (MIPackageItem item@DPIImport{}) = do
+            let DPIImport spec prop alias typ name decls = item
+            (typ', name') <- redirectTFDecl typ name
+            decls' <- mapM declMapper decls
+            let item' = DPIImport spec prop alias typ' name' decls'
+            return $ MIPackageItem item'
+        fullModuleItemMapper (MIPackageItem (DPIExport spec alias kw name)) =
+            return $ MIPackageItem $ DPIExport spec alias kw name
         fullModuleItemMapper (AlwaysC kw stmt) = do
             enterProcedure
             stmt' <- fullStmtMapper stmt

src/Convert/Traverse.hs

@@ -618,6 +618,14 @@ traverseNodesM exprMapper declMapper typeMapper lhsMapper stmtMapper =
         return $ MIPackageItem $ Import x y
     moduleItemMapper (MIPackageItem (Export x y)) =
         return $ MIPackageItem $ Export x y
+    moduleItemMapper (MIPackageItem item@DPIImport{}) = do
+        let DPIImport spec prop alias typ name decls = item
+        typ' <- typeMapper typ
+        decls' <- mapM declMapper decls
+        let item' = DPIImport spec prop alias typ' name decls'
+        return $ MIPackageItem item'
+    moduleItemMapper (MIPackageItem (DPIExport spec alias kw name)) =
+        return $ MIPackageItem $ DPIExport spec alias kw name
     moduleItemMapper (AssertionItem (mx, a)) = do
         a' <- traverseAssertionStmtsM stmtMapper a
         a'' <- traverseAssertionExprsM exprMapper a'

src/Language/SystemVerilog/AST/Description.hs

+{-# LANGUAGE PatternSynonyms #-}
 {- sv2v
  - Author: Zachary Snow <zach@zachjs.com>
  - Initial Verilog AST Author: Tom Hawkins <tomahawkins@gmail.com>
@@ -12,6 +13,8 @@ module Language.SystemVerilog.AST.Description
     , Lifetime    (..)
     , Qualifier   (..)
     , ClassItem
+    , DPIImportProperty (..)
+    , DPIExportKW (..)
     ) where
 
 import Data.List (intercalate)
@@ -22,7 +25,7 @@ import Language.SystemVerilog.AST.ShowHelp
 import Language.SystemVerilog.AST.Attr (Attr)
 import Language.SystemVerilog.AST.Decl (Decl(CommentDecl))
 import Language.SystemVerilog.AST.Stmt (Stmt)
-import Language.SystemVerilog.AST.Type (Type, Identifier)
+import Language.SystemVerilog.AST.Type (Type, Identifier, pattern UnknownType)
 import {-# SOURCE #-} Language.SystemVerilog.AST.ModuleItem (ModuleItem)
 
 data Description
@@ -82,6 +85,8 @@ data PackageItem
     | Export Identifier Identifier
     | Decl Decl
     | Directive String
+    | DPIImport String DPIImportProperty Identifier Type Identifier [Decl]
+    | DPIExport String Identifier DPIExportKW Identifier
     deriving Eq
 
 instance Show PackageItem where
@@ -95,6 +100,22 @@ instance Show PackageItem where
     show (Export x y) = printf "export %s::%s;" (showWildcard x) (showWildcard y)
     show (Decl decl) = show decl
     show (Directive str) = str
+    show (DPIImport spec prop alias typ name decls) =
+        printf "import %s %s%s %s %s(%s);"
+            (show spec) (showPad prop) aliasStr protoStr name declsStr
+        where
+            aliasStr = if null alias then "" else alias ++ " = "
+            protoStr =
+                if typ == UnknownType
+                    then "task"
+                    else "function " ++ show typ
+            declsStr =
+                if null decls
+                    then ""
+                    else "\n\t" ++ showDecls decls ++ "\n"
+    show (DPIExport spec alias kw name) =
+        printf "export %s %s%s %s;" (show spec) aliasStr (show kw) name
+        where aliasStr = if null alias then "" else alias ++ " = "
 
 showWildcard :: Identifier -> String
 showWildcard "" = "*"
@@ -137,3 +158,23 @@ instance Show Qualifier where
     show QStatic    = "static"
     show QLocal     = "local"
     show QProtected = "protected"
+
+data DPIImportProperty
+    = DPIContext
+    | DPIPure
+    | DPINone
+    deriving Eq
+
+instance Show DPIImportProperty where
+    show DPIContext = "context"
+    show DPIPure    = "pure"
+    show DPINone    = ""
+
+data DPIExportKW
+    = DPIExportTask
+    | DPIExportFunction
+    deriving Eq
+
+instance Show DPIExportKW where
+    show DPIExportTask     = "task"
+    show DPIExportFunction = "function"

src/Language/SystemVerilog/AST/Type.hs

@@ -181,6 +181,7 @@ data NonIntegerType
     | TRealtime
     | TString
     | TEvent
+    | TChandle
     deriving Eq
 
 instance Show NetType where
@@ -213,6 +214,7 @@ instance Show NonIntegerType where
     show TRealtime  = "realtime"
     show TString    = "string"
     show TEvent     = "event"
+    show TChandle   = "chandle"
 
 data Packing
     = Unpacked

src/Language/SystemVerilog/Parser/Parse.y

@@ -518,6 +518,7 @@ NonIntegerTypeP :: { (Position, NonIntegerType) }
   | "realtime"  { withPos $1 TRealtime  }
   | "string"    { withPos $1 TString    }
   | "event"     { withPos $1 TEvent     }
+  | "chandle"   { withPos $1 TChandle   }
 
 EnumItems :: { [EnumItem] }
   : EnumItem               { $1 }
@@ -904,6 +905,7 @@ NonDeclPackageItem :: { [PackageItem] }
   | ImportOrExport       { $1 }
   | ForwardTypedef ";"   { $1 }
   | TimeunitsDeclaration { $1 }
+  | DPIImportExport      { [$1] }
   | Directive            { [Directive $1] }
 
 ImportOrExport :: { [PackageItem] }
@@ -931,6 +933,31 @@ TimeunitsDeclaration :: { [PackageItem] }
   | "timeunit" Time "/" Time ";" { [] }
   | "timeprecision" Time     ";" { [] }
 
+DPIImportExport :: { PackageItem }
+  : "import" DPISpecString OptDPIImportProperty OptDPIAlias DPITFProto     { makeDPIImport $2 $3 $4 $5 }
+  | "export" DPISpecString OptDPIAlias          DPIExportKW Identifier ";" { DPIExport $2 $3 $4 $5 }
+
+DPIExportKW :: { DPIExportKW }
+  : "task"     { DPIExportTask }
+  | "function" { DPIExportFunction }
+
+DPISpecString :: { String }
+  : String { $1 }
+
+OptDPIAlias :: { Identifier }
+  : Identifier "=" { $1 }
+  | {- empty -}    { "" }
+
+OptDPIImportProperty :: { DPIImportProperty }
+  : "context"   { DPIContext }
+  | "pure"      { DPIPure }
+  | {- empty -} { DPINone }
+
+DPITFProto :: { (Type, Identifier, [Decl]) }
+  : "function" FuncRetAndName    TFItems { (fst $2     , snd $2, $3) }
+  | "function" "void" Identifier TFItems { (UnknownType,     $3, $4) }
+  | "task"     Identifier        TFItems { (UnknownType,     $2, $3) }
+
 Directive :: { String }
   : "`celldefine"          { tokenString $1 }
   | "`endcelldefine"       { tokenString $1 }
@@ -1742,4 +1769,8 @@ makeEnumItems (_, root) (l, r) base =
         then reverse [r..l]
         else [l..r]
 
+makeDPIImport :: String -> DPIImportProperty -> Identifier
+  -> (Type, Identifier, [Decl]) -> PackageItem
+makeDPIImport a b c (d, e, f) = DPIImport a b c d e f
+
 }

test/nosim/dpi.sv

+module top;
+
+/* From IEEE 1800-2017 Section 35.4 */
+
+export "DPI-C" f_plus = function \f+ ; // "f+" exported as "f_plus"
+export "DPI-C" function f; // "f" exported under its own name
+import "DPI-C" init_1 = function void \init[1] (); // "init_1" is a linkage name
+import "DPI-C" \begin = function void \init[2] (); // "begin" is a linkage name
+
+/* From IEEE 1800-2017 Section 35.5.4 */
+
+import "DPI-C" function void myInit();
+
+// from standard math library
+import "DPI-C" pure function real sin(real foo /* TODO support unnamed params */ );
+
+// from standard C library: memory management
+import "DPI-C" function chandle malloc(int size); // standard C function
+import "DPI-C" function void free(chandle ptr); // standard C functionS
+
+// abstract data structure: queue
+import "DPI-C" function chandle newQueue(input string name_of_queue);
+
+// Note the following import uses the same foreign function for
+// implementation as the prior import, but has different SystemVerilog name
+// and provides a default value for the argument.
+import "DPI-C" newQueue=function chandle newAnonQueue(input string s/* =null TODO support default values */);
+import "DPI-C" function chandle newElem(bit [15:0] foo /* TODO support unnamed params */ );
+import "DPI-C" function void enqueue(chandle queue, chandle elem);
+import "DPI-C" function chandle dequeue(chandle queue);
+
+// miscellanea
+import "DPI-C" function bit [15:0] getStimulus(input integer x);
+import "DPI-C" context function void processTransaction(chandle elem,
+output logic [64:1] arr [0:63]);
+import "DPI-C" task checkResults(input string s, bit [511:0] packet);
+
+endmodule