From 0892b39ad2e43ada3787576c2897b8e60d4d194f Mon Sep 17 00:00:00 2001
From: Geza Lore <gezalore@gmail.com>
Date: Fri, 23 Feb 2024 08:53:42 +0000
Subject: [PATCH] Fix incorrect code generation for change expression on
 typedefed unpacked array (#4915)

---
 src/V3SenExprBuilder.h                  |  5 +++--
 test_regress/t/t_unopt_array.v          | 13 +++++++++----
 test_regress/t/t_unopt_array_typedef.pl | 24 ++++++++++++++++++++++++
 3 files changed, 36 insertions(+), 6 deletions(-)
 create mode 100755 test_regress/t/t_unopt_array_typedef.pl

diff --git a/src/V3SenExprBuilder.h b/src/V3SenExprBuilder.h
index 203f446fb..8d0bba03c 100644
--- a/src/V3SenExprBuilder.h
+++ b/src/V3SenExprBuilder.h
@@ -139,7 +139,8 @@ class SenExprBuilder final {
                 return prevp;
             }
 
-            if (AstUnpackArrayDType* const dtypep = VN_CAST(exprp->dtypep(), UnpackArrayDType)) {
+            if (AstUnpackArrayDType* const dtypep
+                = VN_CAST(exprp->dtypep()->skipRefp(), UnpackArrayDType)) {
                 AstCMethodHard* const cmhp = new AstCMethodHard{flp, wrPrev(), "assign", rdCurr()};
                 cmhp->dtypeSetVoid();
                 m_postUpdates.push_back(cmhp->makeStmt());
@@ -167,7 +168,7 @@ class SenExprBuilder final {
             return {nullptr, false};  // We already warn for this in V3LinkResolve
         case VEdgeType::ET_CHANGED:
         case VEdgeType::ET_HYBRID:  //
-            if (VN_IS(senp->dtypep(), UnpackArrayDType)) {
+            if (VN_IS(senp->dtypep()->skipRefp(), UnpackArrayDType)) {
                 AstCMethodHard* const resultp = new AstCMethodHard{flp, currp(), "neq", prevp()};
                 resultp->dtypeSetBit();
                 return {resultp, true};
diff --git a/test_regress/t/t_unopt_array.v b/test_regress/t/t_unopt_array.v
index 9f3bc9718..899315663 100644
--- a/test_regress/t/t_unopt_array.v
+++ b/test_regress/t/t_unopt_array.v
@@ -74,18 +74,23 @@ module Test (/*AUTOARG*/
    input [31:0] in;
    output wire [31:0] out;
 
-   reg [31:0]        stage [3:0];
+`ifdef USE_TYPEDEF
+   typedef reg [3:0][31:0] stage_t [3:0];
+   stage_t           stage;
+`else
+   reg [3:0][31:0]   stage [3:0];
+`endif
 
    genvar            g;
 
    generate
       for (g=0; g<4; g++) begin
          always_comb begin
-            if (g==0) stage[g] = in;
-            else stage[g] = {stage[g-1][30:0],1'b1};
+            if (g==0) stage[g] = {4{in}};
+            else stage[g] = {4{stage[g-1][0][30:0],1'b1}};
          end
       end
    endgenerate
 
-   assign out = stage[3];
+   assign out = stage[3][0];
 endmodule
diff --git a/test_regress/t/t_unopt_array_typedef.pl b/test_regress/t/t_unopt_array_typedef.pl
new file mode 100755
index 000000000..ecce1d841
--- /dev/null
+++ b/test_regress/t/t_unopt_array_typedef.pl
@@ -0,0 +1,24 @@
+#!/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);
+
+top_filename("t/t_unopt_array.v");
+
+compile(
+    verilator_flags2 => ["-Wno-UNOPTFLAT +define+USE_TYPEDEF"],
+    );
+
+execute(
+    check_finished => 1,
+    );
+
+ok(1);
+1;