Enable simple function localparams (#2461)

include/verilated_save.h

@@ -55,7 +55,7 @@ public:
     }
     virtual ~VerilatedSerialize() {
         close();
-        if (m_bufp) VL_DO_CLEAR(delete [] m_bufp, m_bufp = NULL);
+        if (m_bufp) VL_DO_CLEAR(delete[] m_bufp, m_bufp = NULL);
     }
     // METHODS
     bool isOpen() const { return m_isOpen; }
@@ -118,7 +118,7 @@ public:
     }
     virtual ~VerilatedDeserialize() {
         close();
-        if (m_bufp) VL_DO_CLEAR(delete [] m_bufp, m_bufp = NULL);
+        if (m_bufp) VL_DO_CLEAR(delete[] m_bufp, m_bufp = NULL);
     }
     // METHODS
     bool isOpen() const { return m_isOpen; }

src/V3LinkDot.cpp

@@ -1008,12 +1008,6 @@ class LinkDotFindVisitor : public AstNVisitor {
         // Var: Remember its name for later resolution
         UASSERT_OBJ(m_curSymp && m_modSymp, nodep, "Var not under module?");
         iterateChildren(nodep);
-        if (m_ftaskp && nodep->isParam()) {
-            nodep->v3warn(E_UNSUPPORTED,
-                          "Unsupported: Parameters in functions");  // Big3 unsupported too
-            VL_DO_DANGLING(nodep->unlinkFrBack()->deleteTree(), nodep);
-            return;
-        }
         if (nodep->isFuncLocal() && nodep->lifetime().isStatic()) {
             nodep->v3warn(E_UNSUPPORTED, "Unsupported: 'static' function/task variables");
         } else if (nodep->isClassMember() && nodep->lifetime().isStatic()) {

src/V3Param.cpp

@@ -106,6 +106,8 @@ private:
     typedef std::deque<AstCell*> CellList;
     CellList m_cellps;  // Cells left to process (in this module)
 
+    AstNodeFTask* m_ftaskp;  // Function/task reference
+
     AstNodeModule* m_modp;  // Current module being processed
 
     string m_unlinkedTxt;  // Text for AstUnlinkedRef
@@ -302,6 +304,11 @@ private:
         nodep->user5p(genHierNamep);
         m_cellps.push_back(nodep);
     }
+    virtual void visit(AstNodeFTask* nodep) VL_OVERRIDE {
+        m_ftaskp = nodep;
+        iterateChildren(nodep);
+        m_ftaskp = NULL;
+    }
 
     // Make sure all parameters are constantified
     virtual void visit(AstVar* nodep) VL_OVERRIDE {
@@ -323,6 +330,16 @@ private:
                             new AstAssign(nodep->fileline(),
                                           new AstVarRef(nodep->fileline(), nodep, true),
                                           nodep->valuep()->cloneTree(true))));
+                        if (m_ftaskp) {
+                            // We put the initial in wrong place under a function.  We
+                            // should move the parameter out of the function and to the
+                            // module, with appropriate dotting, but this confuses LinkDot
+                            // (as then name isn't found later), so punt - probably can
+                            // treat as static function variable when that is supported.
+                            nodep->v3warn(
+                                E_UNSUPPORTED,
+                                "Unsupported: Parameters in functions with complex assign");
+                        }
                     }
                 }
             }
@@ -556,6 +573,7 @@ public:
     // CONSTRUCTORS
     explicit ParamVisitor(AstNetlist* nodep) {
         m_longId = 0;
+        m_ftaskp = NULL;
         m_modp = NULL;
         m_nextValue = 1;
         //

test_regress/t/t_param_func2.pl

@@ -0,0 +1,21 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(simulator => 1);
+
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
+
+ok(1);
+1;

test_regress/t/t_param_func2.v

@@ -0,0 +1,52 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2020 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+module t;
+   sub #(.WIDTH(4)) sub4();
+   sub #(.WIDTH(8)) sub8();
+
+   logic [3:0] out4;
+   logic [7:0] out8;
+
+   initial begin
+      out4 = sub4.orer(4'b1000);
+      out8 = sub8.orer(8'b10000000);
+      if (out4 != 4'b1011) $stop;
+      if (out8 != 8'b10111111) $stop;
+      out4 = sub4.orer2(4'b1000);
+      out8 = sub8.orer2(8'b10000000);
+      if (out4 != 4'b1001) $stop;
+      if (out8 != 8'b10011111) $stop;
+      $write("*-* All Finished *-*\n");
+      $finish;
+   end
+endmodule
+
+
+module sub;
+   parameter WIDTH = 1;
+
+   function [WIDTH-1:0] orer;
+      input [WIDTH-1:0] in;
+      // IEEE provices no way to override this parameter, basically it's a localparam
+      parameter MASK_W = WIDTH - 2;
+      localparam [MASK_W-1:0] MASK = '1;
+      // verilator lint_off WIDTH
+      return in | MASK;
+      // verilator lint_on WIDTH
+   endfunction
+
+   function [WIDTH-1:0] orer2;
+      input [WIDTH-1:0] in;
+      // Same param names as other function to check we disambiguate
+      // IEEE provices no way to override this parameter, basically it's a localparam
+      parameter MASK_W = WIDTH - 3;
+      localparam [MASK_W-1:0] MASK = '1;
+      // verilator lint_off WIDTH
+      return in | MASK;
+      // verilator lint_on WIDTH
+   endfunction
+endmodule

test_regress/t/t_param_in_func_bad.out

@@ -1,7 +1,5 @@
-%Error-UNSUPPORTED: t/t_param_in_func_bad.v:24:26: Unsupported: Parameters in functions
+%Error-UNSUPPORTED: t/t_param_in_func_bad.v:24:26: Unsupported: Parameters in functions with complex assign
+                                                 : ... In instance t
    24 |    localparam logic[7:0] digits[10]
       |                          ^~~~~~
-%Error: t/t_param_in_func_bad.v:28:11: Can't find definition of variable: 'digits'
-   28 |    return digits[d];
-      |           ^~~~~~
 %Error: Exiting due to