Add waiver for foreach SIDEEFFECT in future UVM

include/verilated_std_waiver.vlt

@@ -53,6 +53,7 @@ lint_off -rule MISINDENT `VLT_UVM_FILES -match "* rw_access.data=*"
 lint_off -rule MISINDENT `VLT_UVM_FILES -match "* uvm_cmdline_proc =*"
 lint_off -rule REALCVT `VLT_UVM_FILES -match "* m_time *"
 lint_off -rule REALCVT `VLT_UVM_FILES -match "*$realtime*"
+lint_off -rule SIDEEFFECT `VLT_UVM_FILES -match "*foreach (blks[blk_].reg_files[blk_rf])*"
 lint_off -rule SYMRSVDWORD `VLT_UVM_FILES -match "*'delete'*"
 lint_off -rule SYMRSVDWORD `VLT_UVM_FILES -match "*'list'*"
 lint_off -rule SYMRSVDWORD `VLT_UVM_FILES -match "*'map'*"

test_regress/t/t_foreach_sideeff_uvm.py

@@ -0,0 +1,18 @@
+#!/usr/bin/env python3
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2025 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
+
+import vltest_bootstrap
+
+test.scenarios('simulator_st')
+
+test.compile()
+
+test.execute()
+
+test.passes()

test_regress/t/t_foreach_sideeff_uvm.v

@@ -0,0 +1,54 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2025 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+// verilog_format: off
+`define stop $stop
+`define checkd(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d:  got=%0d exp=%0d\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
+// verilog_format: on
+
+typedef struct {int reg_files[int unsigned];} uvm_reg_t;
+
+module t;
+  uvm_reg_t blks[int unsigned];
+
+  initial begin
+    int sum;
+    int inner1_i;
+    int inner2_j;
+
+    blks[1].reg_files[10] = 101;
+    blks[1].reg_files[11] = 102;
+    blks[3].reg_files[20] = 308;
+    blks[3].reg_files[21] = 309;
+
+    foreach (blks[i]) begin
+      // $display("blks[%d]", i);
+      ++inner1_i;
+      // This isn't a 2D foreach, but rather a dotted reference using above loop
+
+      // Vlt considers below blks[i]. a side effect because the AstAssocSel can
+      // create elements, and threw SIDEEFFECT
+      // As this code occurs in UVM, we special case a SIDEEFFECT suppress in
+      // verilated_std_waiver.vlt
+      // Future alternative is to auto-waiver an ArraySel under another ArraySel
+      // with same index in outer loop
+
+      // verilator lint_off SIDEEFFECT
+      foreach (blks[i].reg_files[j]) begin
+        // verilator lint_on SIDEEFFECT
+
+        ++inner2_j;
+        sum += blks[i].reg_files[j];
+        // $display("blks[%d].reg_files[%d]", i, j);
+      end
+    end
+    `checkd(inner1_i, 2);
+    `checkd(inner2_j, 4);
+    `checkd(sum, 820);
+    $finish;
+  end
+
+endmodule