drop unneeded module-scoped references

CHANGELOG.md

@@ -5,6 +5,7 @@
 * Fixed module-level localparams being needlessly inlined when forming longest
   static prefixes, which could cause deep recursion and run out of memory on
   some designs
+* Fixed unneeded scoping of constant function calls used in type lookups
 
 ### Other Enhancements
 

src/Convert/TypeOf.hs

@@ -122,6 +122,11 @@ traverseExprM (Cast (Right size) expr) = do
     expr' <- traverseExprM expr
     size' <- traverseExprM size
     elaborateSizeCast size' expr'
+traverseExprM orig@(Dot (Ident x) f) = do
+    unneeded <- unneededModuleScope x f
+    return $ if unneeded
+        then Ident f
+        else orig
 traverseExprM other =
     traverseSinglyNestedExprsM traverseExprM other
     >>= traverseExprTypesM traverseTypeM
@@ -150,6 +155,21 @@ isStringParam (Ident x) = do
         Just (_, _, typ) -> typ == TypeOf (Ident x)
 isStringParam _ = return False
 
+-- checks if referring to part.wire is needlessly explicit
+unneededModuleScope :: Identifier -> Identifier -> ST Bool
+unneededModuleScope part wire = do
+    accessesLocal <- localAccessesM wire
+    if accessesLocal == accessesTop then
+        return True
+    else if head accessesLocal == head accessesTop then do
+        details <- lookupElemM wire
+        return $ case details of
+            Just (accessesFound, _, _) -> accessesTop == accessesFound
+            _ -> False
+    else
+        return False
+    where accessesTop = [Access part Nil, Access wire Nil]
+
 -- convert TypeOf in a Type
 traverseTypeM :: Type -> ST Type
 traverseTypeM (TypeOf expr) =

test/core/unneeded_scope.sv

+module top;
+    function automatic integer incr;
+        input integer inp;
+        return inp + 1;
+    endfunction
+    parameter P = 3;
+    logic [incr(P):0] x;
+    logic [$bits(x) * 2:0] y, z;
+    if (1) begin
+        assign top.y = {top.x, x};
+    end
+    if (1) begin : blk
+        wire x;
+        assign z = {blk.x, top.x};
+    end
+endmodule

test/core/unneeded_scope.sv.pat

+affirm top.y
+affirm top.x
+affirm blk.x
+affirm incr
+reject top.incr

test/core/unneeded_scope.v

+module top;
+    parameter P = 3;
+    wire [P + 1:0] x;
+    wire [2 * P + 4:0] y, z;
+    assign y = {x, x};
+    generate
+        if (1) begin : blk
+            wire x;
+        end
+    endgenerate
+    assign z = {blk.x, x};
+endmodule

test/lib/functions.sh

@@ -45,6 +45,24 @@ assertConverts() {
     ac_tmpa=$SHUNIT_TMPDIR/ac-conv-tmpa.v
     convert "1st conversion of $ac_file" $ac_tmpa $ac_file
 
+    # check for un/expected output in the converted result
+    ac_pats=$ac_file.pat
+    if [ -f $ac_pats ]; then
+        while read line; do
+            rule=${line:0:6}
+            pattern=${line:7}
+            grep -G "$pattern" < $ac_tmpa > /dev/null
+            matches=$?
+            if [ $rule == "affirm" ]; then
+                assertTrue "conversion of $ac_file does not contain $pattern" $matches
+            elif [ $rule == "reject" ]; then
+                assertFalse "conversion of $ac_file contains $pattern" $matches
+            else
+                fail "unknown rule type: '$rule'"
+            fi
+        done < $ac_pats
+    fi
+
     ac_tmpb=$SHUNIT_TMPDIR/ac-conv-tmpb.v
     convert "2nd conversion of $ac_file" $ac_tmpb $ac_tmpa