updated case inside representation

src/Convert/Inside.hs

@@ -32,8 +32,6 @@ convertModuleItem item =
     item
 
 convertExpr :: Expr -> Expr
-convertExpr (Inside Nil valueRanges) =
-    Inside Nil valueRanges
 convertExpr (Inside expr valueRanges) =
     if length checks == 1
         then head checks
@@ -50,31 +48,25 @@ convertExpr (Inside expr valueRanges) =
 convertExpr other = other
 
 convertStmt :: Stmt -> Stmt
-convertStmt (Case u kw expr items) =
-    if not $ any isSpecialInside exprs then
-        Case u kw expr items
-    else if kw /= CaseN then
-        error $ "cannot use inside with " ++ show kw
-    else if hasSideEffects expr then
+convertStmt (Case u CaseInside expr items) =
+    if hasSideEffects expr then
         Block Seq "" [decl] [stmt]
     else
         foldr ($) defaultStmt $
         map (uncurry $ If NoCheck) $
         zip comps stmts
     where
-        exprs = map fst items
         -- evaluate expressions with side effects once
         tmp = "sv2v_temp_" ++ shortHash expr
         decl = Variable Local (TypeOf expr) tmp [] expr
-        stmt = convertStmt (Case u kw (Ident tmp) items)
+        stmt = convertStmt (Case u CaseInside (Ident tmp) items)
         -- underlying inside case elaboration
         itemsNonDefault = filter (not . null . fst) items
-        isSpecialInside :: [Expr] -> Bool
-        isSpecialInside [Inside Nil _] = True
-        isSpecialInside _ = False
         makeComp :: [Expr] -> Expr
-        makeComp [Inside Nil ovr] = Inside expr ovr
-        makeComp _ = error "internal invariant violated"
+        makeComp = Inside expr . map unwrap
+        unwrap :: Expr -> ExprOrRange
+        unwrap (Range Nil NonIndexed r) = Right r
+        unwrap e = Left e
         comps = map (makeComp . fst) itemsNonDefault
         stmts = map snd itemsNonDefault
         defaultStmt = fromMaybe Null (lookup [] items)

src/Language/SystemVerilog/AST/Stmt.hs

@@ -28,7 +28,7 @@ import Text.Printf (printf)
 import Language.SystemVerilog.AST.ShowHelp (commas, indent, unlines', showPad, showBlock)
 import Language.SystemVerilog.AST.Attr (Attr)
 import Language.SystemVerilog.AST.Decl (Decl)
-import Language.SystemVerilog.AST.Expr (Expr(Inside, Nil), Args(..), showExprOrRange)
+import Language.SystemVerilog.AST.Expr (Expr(Nil), Args(..))
 import Language.SystemVerilog.AST.LHS (LHS)
 import Language.SystemVerilog.AST.Op (AsgnOp(AsgnOpEq))
 import Language.SystemVerilog.AST.Type (Identifier)
@@ -65,8 +65,11 @@ instance Show Stmt where
             header = if null name then "" else " : " ++ name
             body = showBlock decls stmts
     show (Case u kw e cs) =
-        printf "%s%s (%s)\n%s\nendcase" (showPad u) (show kw) (show e) bodyStr
-        where bodyStr = indent $ unlines' $ map showCase cs
+        printf "%s%s (%s)%s\n%s\nendcase" (showPad u) (show kw) (show e)
+            insideStr bodyStr
+        where
+            insideStr = if kw == CaseInside then " inside" else ""
+            bodyStr = indent $ unlines' $ map showCase cs
     show (For inits cond assigns stmt) =
         printf "for (%s; %s; %s)\n%s"
             (showInits inits)
@@ -140,19 +143,20 @@ showCase (a, b) = printf "%s:%s" exprStr (showShortBranch b)
     where
         exprStr = case a of
             [] -> "default"
-            [Inside Nil c] -> commas $ map showExprOrRange c
             _ -> commas $ map show a
 
 data CaseKW
     = CaseN
     | CaseZ
     | CaseX
+    | CaseInside
     deriving Eq
 
 instance Show CaseKW where
     show CaseN = "case"
     show CaseZ = "casez"
     show CaseX = "casex"
+    show CaseInside = "case"
 
 type Case = ([Expr], Stmt)
 

src/Language/SystemVerilog/Parser/Parse.y

@@ -1002,7 +1002,7 @@ StmtNonBlock :: { Stmt }
   | Unique "if" "(" Expr ")" Stmt "else" Stmt  { If $1 $4 $6 $8   }
   | Unique "if" "(" Expr ")" Stmt %prec NoElse { If $1 $4 $6 Null }
   | "for" "(" ForInit ForCond ForStep ")" Stmt { For $3 $4 $5 $7 }
-  | Unique CaseKW "(" Expr ")" Cases "endcase" { Case $1 $2 $4 $6 }
+  | CaseStmt                                   { $1 }
   | TimingControl Stmt                         { Timing $1 $2 }
   | "return" ExprOrNil ";"                     { Return $2 }
   | "break"       ";"                          { Break }
@@ -1018,6 +1018,10 @@ StmtNonBlock :: { Stmt }
   | ProceduralAssertionStatement               { Assertion $1 }
   | "void" "'" "(" Expr CallArgs ")" ";"       { Subroutine $4 $5 }
 
+CaseStmt :: { Stmt }
+  : Unique CaseKW "(" Expr ")"          Cases       "endcase" { Case $1 $2                   $4 $ validateCases $5 $6 }
+  | Unique CaseKW "(" Expr ")" "inside" InsideCases "endcase" { Case $1 (caseInsideKW $3 $2) $4 $ validateCases $5 $7 }
+
 BlockKWPar :: { BlockKW }
   : "fork" { Par }
 BlockKWSeq :: { BlockKW }
@@ -1127,12 +1131,16 @@ CaseKW :: { CaseKW }
   | "casez" { CaseZ }
 
 Cases :: { [Case] }
-  : opt("inside") InsideCases { validateCases $1 $2 }
-InsideCases :: { [([ExprOrRange], Stmt)] }
+  : Case       { [$1] }
+  | Case Cases { $1 : $2 }
+Case :: { Case }
+  : Exprs ":"  Stmt { ($1, $3) }
+  | "default" opt(":") Stmt { ([], $3) }
+InsideCases :: { [Case] }
   : InsideCase             { [$1] }
-  | InsideCases InsideCase { $1 ++ [$2] }
-InsideCase :: { ([ExprOrRange], Stmt) }
-  : OpenRangeList ":"  Stmt { ($1, $3) }
+  | InsideCase InsideCases { $1 : $2 }
+InsideCase :: { Case }
+  : OpenRangeList ":"  Stmt { (map rangeAsExpr $1, $3) }
   | "default" opt(":") Stmt { ([], $3) }
 
 Real :: { String }
@@ -1299,7 +1307,7 @@ GenItem :: { GenItem }
 ConditionalGenerateConstruct :: { GenItem }
   : "if" "(" Expr ")" GenItemOrNull "else" GenItemOrNull { GenIf $3 $5 $7      }
   | "if" "(" Expr ")" GenItemOrNull %prec NoElse         { GenIf $3 $5 GenNull }
-  | "case" "(" Expr ")" GenCases "endcase" { GenCase $3 $5 }
+  | "case" "(" Expr ")" GenCases "endcase" { GenCase $3 $ validateCases $4 $5 }
 LoopGenerateConstruct :: { GenItem }
   : "for" "(" GenvarInitialization ";" Expr ";" GenvarIteration ")" GenItem { $3 $5 $7 $9 }
 
@@ -1308,7 +1316,7 @@ GenBlock :: { (Identifier, [GenItem]) }
 
 GenCases :: { [GenCase] }
   : GenCase          { [$1] }
-  | GenCases GenCase { validateGenCases $ $1 ++ [$2] }
+  | GenCase GenCases { $1 : $2 }
 GenCase :: { GenCase }
   : Exprs         ":"  GenItemOrNull { ($1, $3) }
   | "default" opt(":") GenItemOrNull { ([], $3) }
@@ -1444,34 +1452,21 @@ fieldDecl t (x, rs2) =
   (tf $ rs2 ++ rs1, x)
   where (tf, rs1) = typeRanges t
 
-validateCases :: Maybe Token -> [([ExprOrRange], Stmt)] -> [Case]
-validateCases Nothing items =
-  if length (filter null exprs) <= 1
-    then zip exprs' stmts
-    else error $ "multiple default cases: " ++ show items
-  where
-    (exprs, stmts) = unzip items
-    exprs' = map (map unwrap) exprs
-    unwrap (Left expr) = expr
-    unwrap (Right range) =
-      error $ "illegal use of a range (" ++ show range
-        ++ ") in a non-inside case"
-validateCases (Just _) items =
-  if length (filter null sets) <= 1
-    then zip sets' stmts
-    else error $ "multiple default cases: " ++ show items
-  where
-    (sets, stmts) = unzip items
-    sets' = map unwrap sets
-    unwrap [] = []
-    unwrap ls = [Inside Nil ls]
-
-validateGenCases :: [GenCase] -> [GenCase]
-validateGenCases items =
-  if length (filter null exprs) <= 1
+validateCases :: Token -> [([Expr], a)] -> [([Expr], a)]
+validateCases tok items =
+  if length (filter (null . fst) items) <= 1
     then items
-    else error $ "multiple default generate cases: " ++ show items
-  where
-    (exprs, _) = unzip items
+    else error $ show (tokenPosition tok)
+          ++ ": Parse error: case has multiple defaults"
+
+caseInsideKW :: Token -> CaseKW -> CaseKW
+caseInsideKW _ CaseN = CaseInside
+caseInsideKW tok kw =
+  error $ show (tokenPosition tok)
+    ++ ": Parse error: cannot use inside with " ++ show kw
+
+rangeAsExpr :: ExprOrRange -> Expr
+rangeAsExpr (Left e) = e
+rangeAsExpr (Right r) = Range Nil NonIndexed r
 
 }

test/error/case_multiple_defaults.sv

@@ -0,0 +1,10 @@
+// pattern: case has multiple defaults
+module top;
+    initial
+        case (0)
+            0: $display("FOO");
+            1: $display("BAR");
+            default: $display("A");
+            default: $display("B");
+        endcase
+endmodule

test/error/casex_inside.sv

@@ -0,0 +1,8 @@
+// pattern: cannot use inside with casex
+module top;
+    initial
+        casex (0) inside
+            0: $display("FOO");
+            1: $display("BAR");
+        endcase
+endmodule

test/error/casez_inside.sv

@@ -0,0 +1,8 @@
+// pattern: cannot use inside with casez
+module top;
+    initial
+        casez (0) inside
+            0: $display("FOO");
+            1: $display("BAR");
+        endcase
+endmodule

test/error/generate_case_multiple_defaults.sv

@@ -0,0 +1,9 @@
+// pattern: case has multiple defaults
+module top;
+    case (0)
+        0: wire w;
+        1: wire x;
+        default: wire y;
+        default: wire z;
+    endcase
+endmodule