From 924fe235a9127803435df1e62d65409bc8ca8012 Mon Sep 17 00:00:00 2001
From: Stefan Wallentowitz <stefan@wallentowitz.de>
Date: Fri, 3 Jan 2020 13:44:45 +0100
Subject: [PATCH] No assign alias for unpacked public variables (#2089)

Public variables are all emitted in the C code and unpacked arrays
arrays are sliced up for this. After inlining public unpacked array
assignments should not be alias assignments but actual assignments, so
that they are sliced and hence emitted properly.

Fixes #2073
---
 src/V3Inline.cpp                          |  9 +++++++++
 test_regress/t/t_array_unpacked_public.pl | 21 +++++++++++++++++++++
 test_regress/t/t_array_unpacked_public.v  | 21 +++++++++++++++++++++
 3 files changed, 51 insertions(+)
 create mode 100755 test_regress/t/t_array_unpacked_public.pl
 create mode 100644 test_regress/t/t_array_unpacked_public.v

diff --git a/src/V3Inline.cpp b/src/V3Inline.cpp
index 14d384f61..df4125848 100644
--- a/src/V3Inline.cpp
+++ b/src/V3Inline.cpp
@@ -322,6 +322,15 @@ private:
                     new AstAssignW(nodep->fileline(),
                                    new AstVarRef(nodep->fileline(), exprvarrefp->varp(), true),
                                    new AstVarRef(nodep->fileline(), nodep, false)));
+            } else if (nodep->isSigPublic() && VN_IS(nodep->dtypep(), UnpackArrayDType)) {
+                // Public variable at this end and it is an unpacked array. We need to assign
+                // instead of aliased, because otherwise it will pass V3Slice and invalid
+                // code will be emitted.
+                UINFO(9,"assign to public and unpacked: "<<nodep<<endl);
+                m_modp->addStmtp(
+                    new AstAssignW(nodep->fileline(),
+                                   new AstVarRef(nodep->fileline(), exprvarrefp->varp(), true),
+                                   new AstVarRef(nodep->fileline(), nodep, false)));
             } else if (nodep->isIfaceRef()) {
                 m_modp->addStmtp(
                     new AstAssignVarScope(nodep->fileline(),
diff --git a/test_regress/t/t_array_unpacked_public.pl b/test_regress/t/t_array_unpacked_public.pl
new file mode 100755
index 000000000..1bb1cc973
--- /dev/null
+++ b/test_regress/t/t_array_unpacked_public.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/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.
+
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => ["--public-flat-rw"],
+    );
+
+execute(
+    check_finished => 1,
+    );
+
+ok(1);
+1;
diff --git a/test_regress/t/t_array_unpacked_public.v b/test_regress/t/t_array_unpacked_public.v
new file mode 100644
index 000000000..556b85a98
--- /dev/null
+++ b/test_regress/t/t_array_unpacked_public.v
@@ -0,0 +1,21 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2020 by Stefan Wallentowitz
+
+module t();
+  logic din [0:15];
+
+  array_test array_test_inst(.din(din));
+
+  initial begin
+    $write("*-* All Finished *-*\n");
+    $finish;
+  end
+endmodule
+
+module array_test(
+    input din [0:15]
+);
+
+endmodule
\ No newline at end of file