Fix DPI export trigger sensitivity in 'nba'

Fixes #3508

src/V3Sched.cpp

@@ -416,21 +416,6 @@ struct TriggerKit {
 
     VL_UNCOPYABLE(TriggerKit);
 
-    // Create an AstSenTree that is sensitive to the given trigger index. Must not exist yet!
-    AstSenTree* createTriggerSenTree(AstNetlist* netlistp, uint32_t index) const {
-        AstTopScope* const topScopep = netlistp->topScopep();
-        FileLine* const flp = topScopep->fileline();
-        AstVarRef* const vrefp = new AstVarRef{flp, m_vscp, VAccess::READ};
-        AstCMethodHard* const callp
-            = new AstCMethodHard{flp, vrefp, "at", new AstConst{flp, index}};
-        callp->dtypeSetBit();
-        callp->pure(true);
-        AstSenItem* const senItemp = new AstSenItem{flp, VEdgeType::ET_TRUE, callp};
-        AstSenTree* const resultp = new AstSenTree{flp, senItemp};
-        topScopep->addSenTreep(resultp);
-        return resultp;
-    }
-
     // Utility that assigns the given index trigger to fire when the given variable is zero
     void addFirstIterationTriggerAssignment(AstVarScope* counterp, uint32_t index) const {
         FileLine* const flp = counterp->fileline();
@@ -459,6 +444,20 @@ struct TriggerKit {
     }
 };
 
+// Create an AstSenTree that is sensitive to the given trigger index. Must not exist yet!
+AstSenTree* createTriggerSenTree(AstNetlist* netlistp, AstVarScope* const vscp, uint32_t index) {
+    AstTopScope* const topScopep = netlistp->topScopep();
+    FileLine* const flp = topScopep->fileline();
+    AstVarRef* const vrefp = new AstVarRef{flp, vscp, VAccess::READ};
+    AstCMethodHard* const callp = new AstCMethodHard{flp, vrefp, "at", new AstConst{flp, index}};
+    callp->dtypeSetBit();
+    callp->pure(true);
+    AstSenItem* const senItemp = new AstSenItem{flp, VEdgeType::ET_TRUE, callp};
+    AstSenTree* const resultp = new AstSenTree{flp, senItemp};
+    topScopep->addSenTreep(resultp);
+    return resultp;
+}
+
 //============================================================================
 // Utility for extra trigger allocation
 
@@ -727,7 +726,8 @@ void createSettle(AstNetlist* netlistp, SenExprBuilder& senExprBulider,
     invertAndMergeSenTreeMap(trigToSen, trig.m_map);
 
     // First trigger is for pure combinational triggers (first iteration)
-    AstSenTree* const inputChanged = trig.createTriggerSenTree(netlistp, firstIterationTrigger);
+    AstSenTree* const inputChanged
+        = createTriggerSenTree(netlistp, trig.m_vscp, firstIterationTrigger);
 
     // Create and the body function
     AstCFunc* const stlFuncp = V3Order::order(
@@ -800,11 +800,12 @@ AstNode* createInputCombLoop(AstNetlist* netlistp, SenExprBuilder& senExprBuilde
     invertAndMergeSenTreeMap(trigToSen, trig.m_map);
 
     // The trigger top level inputs (first iteration)
-    AstSenTree* const inputChanged = trig.createTriggerSenTree(netlistp, firstIterationTrigger);
+    AstSenTree* const inputChanged
+        = createTriggerSenTree(netlistp, trig.m_vscp, firstIterationTrigger);
 
     // The DPI Export trigger
     AstSenTree* const dpiExportTriggered
-        = trig.createTriggerSenTree(netlistp, dpiExportTriggerIndex);
+        = createTriggerSenTree(netlistp, trig.m_vscp, dpiExportTriggerIndex);
 
     // Create and Order the body function
     AstCFunc* const icoFuncp
@@ -1077,13 +1078,13 @@ void schedule(AstNetlist* netlistp) {
     invertAndMergeSenTreeMap(trigToSenAct, actTrigMap);
 
     // The DPI Export trigger AstSenTree
-    AstSenTree* const dpiExportTriggered
+    AstSenTree* const dpiExportTriggeredAct
-        = actTrig.createTriggerSenTree(netlistp, dpiExportTriggerIndex);
+        = createTriggerSenTree(netlistp, actTrig.m_vscp, dpiExportTriggerIndex);
 
     AstCFunc* const actFuncp = V3Order::order(
         netlistp, {&logicRegions.m_pre, &logicRegions.m_act, &logicReplicas.m_act}, trigToSenAct,
         "act", false, false, [=](const AstVarScope* vscp, std::vector<AstSenTree*>& out) {
-            if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggered);
+            if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggeredAct);
         });
     splitCheck(actFuncp);
     if (v3Global.opt.stats()) V3Stats::statsStage("sched-create-act");
@@ -1098,10 +1099,13 @@ void schedule(AstNetlist* netlistp) {
     std::unordered_map<const AstSenItem*, const AstSenTree*> trigToSenNba;
     invertAndMergeSenTreeMap(trigToSenNba, nbaTrigMap);
 
+    AstSenTree* const dpiExportTriggeredNba
+        = createTriggerSenTree(netlistp, nbaTrigVscp, dpiExportTriggerIndex);
+
     AstCFunc* const nbaFuncp = V3Order::order(
         netlistp, {&logicRegions.m_nba, &logicReplicas.m_nba}, trigToSenNba, "nba",
         v3Global.opt.mtasks(), false, [=](const AstVarScope* vscp, std::vector<AstSenTree*>& out) {
-            if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggered);
+            if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggeredNba);
         });
     splitCheck(nbaFuncp);
     netlistp->evalNbap(nbaFuncp);  // Remember for V3LifePost

test_regress/t/t_order_dpi_export_8.cpp

@@ -0,0 +1,16 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+//
+// Copyright 2022 by Geza Lore. 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
+//
+//*************************************************************************
+
+#include <svdpi.h>
+
+#include <Vt_order_dpi_export_8__Dpi.h>
+
+void call_set_x(svBit val) { set_x(val); }

test_regress/t/t_order_dpi_export_8.pl

@@ -0,0 +1,22 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(vlt_all => 1);
+
+compile(
+    verilator_flags2 => ["--exe", "$Self->{t_dir}/$Self->{name}.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
+
+ok(1);
+1;

test_regress/t/t_order_dpi_export_8.v

@@ -0,0 +1,48 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// Copyright 2022 by Geza Lore. 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
+
+module testbench(
+                 /*AUTOARG*/
+   // Inputs
+   clk
+   );
+
+   input clk; // Top level input clock
+
+   bit x = 0;
+
+   wire y = x & $c(1);
+
+   export "DPI-C" function set_x;
+   function void set_x(bit val);
+      x = val;
+   endfunction;
+
+   import "DPI-C" context function void call_set_x(bit val);
+
+   bit q = 0;
+   always @(posedge clk) q <= ~q;
+
+   always @(edge q) call_set_x(q);
+
+   int n = 0;
+
+   always @(edge clk) begin
+      // This always block needs to evaluate before the NBA to even_other
+      // above is committed, as setting clocks via the set_other_clk uses
+      // blocking assignment.
+      $display("t=%t q=%d x=%d y=%d", $time, q, x, y);
+      if (y !== q) $stop;
+      if (n == 20) begin
+         $write("*-* All Finished *-*\n");
+         $finish;
+      end
+      n += 1;
+   end
+
+endmodule