avoid unnecessary casts on substituted hierarchical constants

src/Convert/Cast.hs

@@ -99,7 +99,7 @@ traverseStmtM stmt = do
     return stmt'
 
 traverseExprM :: Expr -> SC Expr
-traverseExprM (Cast (Left (IntegerVector _ sg rs)) value) = do
+traverseExprM (Cast (Left (IntegerVector kw sg rs)) value) | kw /= TBit = do
     value' <- traverseExprM value
     size' <- traverseExprM size
     convertCastM size' value' signed

src/Convert/HierConst.hs

@@ -71,7 +71,10 @@ traverseDeclM decl = do
             scopeExpr e >>= insertElem x . Right
         Param Localparam (Implicit sg rs) x e ->
             scopeExpr (Cast (Left t) e) >>= insertElem x . Right
-            where t = IntegerVector TLogic sg rs
+            where t = IntegerVector TBit sg rs
+        Param Localparam (IntegerVector _ sg rs) x e ->
+            scopeExpr (Cast (Left t) e) >>= insertElem x . Right
+            where t = IntegerVector TBit sg rs
         Param Localparam t x e ->
             scopeExpr (Cast (Left t) e) >>= insertElem x . Right
         _ -> return ()

test/core/struct_hier_nocast.sv

@@ -0,0 +1,19 @@
+module top;
+    typedef struct packed {
+        int A;
+        byte B;
+        shortint C;
+    } T;
+    localparam T Q = '{ A: 1, B: 2, C: 3 };
+    if (1) begin : blk
+        localparam T P = Q;
+        logic [P.A - 1:0] a;
+        logic [P.B - 1:0] b;
+        logic [P.C - 1:0] c;
+    end
+    initial begin
+        $display("%b", $bits(blk.a));
+        $display("%b", $bits(blk.b));
+        $display("%b", $bits(blk.c));
+    end
+endmodule

test/core/struct_hier_nocast.v

@@ -0,0 +1,7 @@
+module top;
+    initial begin
+        $display("%b", 32'd1);
+        $display("%b", 8'd2);
+        $display("%b", 16'd3);
+    end
+endmodule