From 3979d294eb7bbf4c4f22096234c15ab1e67ce5d3 Mon Sep 17 00:00:00 2001
From: Zachary Snow <zach@zachjs.com>
Date: Sat, 12 Oct 2019 11:40:36 -0400
Subject: [PATCH] consistent size casting behavior

- also adds $clog2 localparam substitution to Simplify
---
 src/Convert/Enum.hs                    |  9 +------
 src/Convert/Simplify.hs                | 36 +++++++++++++++-----------
 src/Language/SystemVerilog/AST/Expr.hs | 25 ------------------
 test/basic/cast.sv                     |  8 ++++++
 test/basic/cast.v                      |  8 ++++++
 5 files changed, 38 insertions(+), 48 deletions(-)

diff --git a/src/Convert/Enum.hs b/src/Convert/Enum.hs
index 8ac3b8e..adacd1e 100644
--- a/src/Convert/Enum.hs
+++ b/src/Convert/Enum.hs
@@ -93,17 +93,10 @@ toItem :: EnumItem -> PackageItem
 toItem ((mr, x), v) =
     Decl $ Param Localparam itemType x v'
     where
-        v' = if mr == Nothing
-                then simplify v
-                else sizedExpr x (rangeSize r) (simplify v)
+        v' = simplify v
         rs = maybe [] (\a -> [a]) mr
-        r = defaultRange mr
         itemType = Implicit Unspecified rs
 
-defaultRange :: Maybe Range -> Range
-defaultRange Nothing = (Number "0", Number "0")
-defaultRange (Just r) = r
-
 toBaseType :: Maybe Type -> Type
 toBaseType Nothing = defaultType
 toBaseType (Just (Implicit _ rs)) =
diff --git a/src/Convert/Simplify.hs b/src/Convert/Simplify.hs
index f217e69..368271b 100644
--- a/src/Convert/Simplify.hs
+++ b/src/Convert/Simplify.hs
@@ -49,31 +49,37 @@ traverseExprM = traverseNestedExprsM $ stately convertExpr
 
 convertExpr :: Info -> Expr -> Expr
 convertExpr info (Cast (Right c) e) =
-    case c' of
-        Number _ ->
-            if sized == e
-                then Cast (Right c') e
-                else sized
-        _ -> Cast (Right c') e
+    Cast (Right c') e
     where
-        c' = simplify $ traverseNestedExprs (substitute info) (simplify c)
-        sized = sizedExpr "" c' e
+        c' = simplify $ substitute info c
 convertExpr info (DimFn f v e) =
     DimFn f v e'
     where
-        e' = simplify $ traverseNestedExprs (substitute info) e
+        e' = simplify $ substitute info e
+convertExpr info (Call Nothing "$clog2" (Args [Just e] [])) =
+    if clog2' == clog2
+        then clog2
+        else clog2'
+    where
+        e' = simplify $ substitute info e
+        clog2 = Call Nothing "$clog2" (Args [Just e'] [])
+        clog2' = simplify clog2
 convertExpr info (Mux cc aa bb) =
     if before == after
         then Mux cc aa bb
         else simplify $ Mux after aa bb
     where
-        before = traverseNestedExprs (substitute info) (simplify cc)
+        before = substitute info cc
         after = simplify before
 convertExpr _ other = other
 
 substitute :: Info -> Expr -> Expr
-substitute info (Ident x) =
-    case Map.lookup x info of
-        Nothing -> Ident x
-        Just e -> e
-substitute _ other = other
+substitute info expr =
+    traverseNestedExprs substitute' $ simplify expr
+    where
+        substitute' :: Expr -> Expr
+        substitute' (Ident x) =
+            case Map.lookup x info of
+                Nothing -> Ident x
+                Just e -> e
+        substitute' other = other
diff --git a/src/Language/SystemVerilog/AST/Expr.hs b/src/Language/SystemVerilog/AST/Expr.hs
index 478fe35..25fb242 100644
--- a/src/Language/SystemVerilog/AST/Expr.hs
+++ b/src/Language/SystemVerilog/AST/Expr.hs
@@ -19,7 +19,6 @@ module Language.SystemVerilog.AST.Expr
     , rangeSize
     , endianCondExpr
     , endianCondRange
-    , sizedExpr
     , dimensionsSize
     , readNumber
     ) where
@@ -271,30 +270,6 @@ endianCondRange r r1 r2 =
     , endianCondExpr r (snd r1) (snd r2)
     )
 
--- attempts to make a number literal have an explicit size
-sizedExpr :: Identifier -> Expr -> Expr -> Expr
-sizedExpr x s (Number n) =
-    if size /= show resSize
-        then error $ "literal " ++ show n ++ " for " ++ show x
-                ++ " doesn't have size " ++ show size
-        else Number res
-    where
-        size =
-            case simplify s of
-                Number v -> v
-                other -> error $ "could not simplify sizedExpr: " ++ show other
-        unticked = case n of
-            '\'' : rest -> rest
-            rest -> rest
-        resSize = (read $ takeWhile (/= '\'') res) :: Int
-        res = case readMaybe unticked :: Maybe Int of
-            Nothing ->
-                if unticked == n
-                    then n
-                    else size ++ n
-            Just num -> size ++ "'d" ++ show num
-sizedExpr _ _ e = e
-
 dimensionsSize :: [Range] -> Expr
 dimensionsSize ranges =
     simplify $
diff --git a/test/basic/cast.sv b/test/basic/cast.sv
index 99fe1e4..93febe3 100644
--- a/test/basic/cast.sv
+++ b/test/basic/cast.sv
@@ -1,4 +1,5 @@
 module top;
+
     parameter WIDTH = 32;
     initial begin
         logic [31:0] w = 1234;
@@ -22,7 +23,14 @@ module top;
         $display("%0d %0d", y, ($clog2(WIDTH))'(y));
         $display("%0d %0d", z, ($clog2(WIDTH))'(z));
     end
+
     localparam bit foo = '0;
     localparam logic [31:0] bar = 32'(foo);
     initial $display("%b %b", foo, bar);
+
+    initial begin
+        $display("%b", 5'('1));
+        $display("%b", 5'(1'sb1));
+    end
+
 endmodule
diff --git a/test/basic/cast.v b/test/basic/cast.v
index 99fd8aa..9b15639 100644
--- a/test/basic/cast.v
+++ b/test/basic/cast.v
@@ -1,4 +1,5 @@
 module top;
+
     initial begin : foo_block
         reg [31:0] w;
         reg signed [31:0] x;
@@ -25,7 +26,14 @@ module top;
         $display("%0d %0d", y, $signed(y[4:0]));
         $display("%0d %0d", z, z[4:0]);
     end
+
     localparam [0:0] foo = 0;
     localparam [31:0] bar = 32'b0;
     initial $display("%b %b", foo, bar);
+
+    initial begin
+        $display("%b", 5'sb11111);
+        $display("%b", 5'sb11111);
+    end
+
 endmodule