feat: Add V3DumpSignals-Pass

src/CMakeLists.txt

@@ -84,6 +84,7 @@ set(HEADERS
     V3DfgPeepholePatterns.h
     V3DfgVertices.h
     V3DiagSarif.h
+    V3DumpSignals.h
     V3DupFinder.h
     V3EmitC.h
     V3EmitCBase.h
@@ -251,6 +252,7 @@ set(COMMON_SOURCES
     V3DfgRegularize.cpp
     V3DfgSynthesize.cpp
     V3DiagSarif.cpp
+    V3DumpSignals.cpp
     V3DupFinder.cpp
     V3EmitCBase.cpp
     V3EmitCConstPool.cpp

src/Makefile_obj.in

@@ -269,6 +269,7 @@ RAW_OBJS_PCH_ASTNOMT = \
   V3DfgRegularize.o \
   V3DfgSynthesize.o \
   V3DiagSarif.o \
+  V3DumpSignals.o \
   V3DupFinder.o \
   V3EmitCMain.o \
   V3EmitCMake.o \

src/V3DumpSignals.cpp

@@ -0,0 +1,117 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+// DESCRIPTION: Verilator:
+//
+// Code available from: https://verilator.org
+//
+//*************************************************************************
+//
+// Copyright 2003-2025 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
+//
+//*************************************************************************
+//
+//*************************************************************************
+
+#include "V3PchAstNoMT.h"  // VL_MT_DISABLED_CODE_UNIT
+
+#include "V3DumpSignals.h"
+
+#include "V3Global.h"
+
+#include <iostream>
+#include <fstream>
+#include <string>
+
+VL_DEFINE_DEBUG_FUNCTIONS;
+V3Global v3global;
+
+class DumpSignals final : public VNVisitor {
+    bool m_firstModuleNode = true;
+    bool m_foundCell = false;
+    string m_currHier;
+    std::ofstream m_signalFile;
+
+    // Methods
+    void processVar(AstVar* varp) {
+        if (varp->basicp() && varp->basicp()->name() != "") {
+                        bool hasRangep = varp->basicp()->rangep() != nullptr;
+                        bool isSized = varp->basicp()->widthSized();
+                        if (hasRangep) {
+                            std::string varHier = m_currHier + varp->name() + " : Type[" + varp->basicp()->name() + "] Width[" + std::to_string(varp->basicp()->rangep()->elementsConst()) + "]";
+                            m_signalFile << varHier << "\n";
+                        } else {
+                            if (varp->basicp()->implicit()){
+                                // Since Var is implicit set the width to 1 like in V3Width.cpp in the AstVar visitor
+                                std::string varHier = m_currHier + varp->name() + " : Type[" + varp->basicp()->name() + "] Width[" + std::to_string(1) + "]";
+                                m_signalFile << varHier << "\n";
+                            } else {
+                                std::string varHier = m_currHier + varp->name() + " : Type[" + varp->basicp()->name() + "] Width[" + std::to_string(varp->basicp()->width()) + "]";
+                                m_signalFile << varHier << "\n";
+                            }
+                        }
+                    }
+    }
+
+    void processChildrenNode(AstNode* nodep) {
+        for (AstNode* n = nodep->op2p(); n; n = n->nextp()) {
+                if (VN_IS(n, Var)) {
+                    AstVar* varp = VN_AS(n, Var);
+                    if (!varp->isParam() && !varp->isGenVar() && !varp->isIfaceRef() && !varp->isIfaceParent()) {
+                        processVar(varp);
+                    }
+                } else if (VN_IS(n, Cell)) {
+                    if (VN_IS(VN_AS(n, Cell)->modp(), Module)) {
+                        m_foundCell = true;
+                        std::string oldHier = m_currHier;
+                        m_currHier += n->name() + ".";
+                        diveIntoCellModp(VN_AS(n, Cell)->modp());
+                        m_currHier = oldHier;
+                    }
+                }
+            }
+    }
+
+    void diveIntoCellModp(AstNodeModule* modp) {
+        processChildrenNode(modp);
+    }
+
+    // VISITORS
+    void visit(AstModule* nodep) override {
+        if (m_firstModuleNode) {
+            m_currHier = nodep->name() + ".";
+            processChildrenNode(nodep);
+            m_firstModuleNode = false;
+        }
+    }
+
+    //-----------------
+    void visit(AstNode* nodep) override {
+        iterateChildren(nodep);
+    }
+
+public:
+    explicit DumpSignals(AstNetlist* nodep) {
+        std::string filePath = v3global.opt.hierTopDataDir() + "/signalDump.log";
+        m_signalFile.open(filePath);
+        iterate(nodep);
+    }
+
+    ~DumpSignals() override {
+        if (m_signalFile.is_open()) {
+            m_signalFile.close();
+        }
+    }
+};
+
+//##################################################################################
+// DumpSignals class functions
+
+void V3DumpSignals::dumpSignals(AstNetlist* nodep) {
+    UINFO(2, __FUNCTION__ << ": " << endl);
+    { DumpSignals{nodep}; }
+    V3Global::dumpCheckGlobalTree("dumpSignals", 0, dumpTreeEitherLevel() >= 3);
+}

src/V3DumpSignals.h

@@ -0,0 +1,32 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+// DESCRIPTION: Verilator:
+//
+// Code available from: https://verilator.org
+//
+//*************************************************************************
+//
+// Copyright 2003-2025 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
+//
+//*************************************************************************
+
+#ifndef VERILATOR_V3DUMPSIGNALS_H_
+#define VERILATOR_V3DUMPSIGNALS_H_
+
+#include "config_build.h"
+#include "verilatedos.h"
+
+class AstNetlist;
+
+//=========================================================================
+
+class V3DumpSignals final {
+public:
+    static void dumpSignals(AstNetlist* nodep) VL_MT_DISABLED;
+};
+
+#endif  // Guard

src/V3Options.cpp

@@ -1947,6 +1947,7 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc,
     });
 
     DECL_OPTION("-instrument", OnOff, &m_instrument);
+    DECL_OPTION("-dump-signals", OnOff, &m_dumpSignals);
 
     parser.finalize();
 

src/V3Options.h

@@ -250,6 +250,7 @@ private:
     bool m_decorationNodes = false;  // main switch: --decoration=nodes
     bool m_diagnosticsSarif = false;  // main switch: --diagnostics-sarif
     bool m_dpiHdrOnly = false;      // main switch: --dpi-hdr-only
+    bool m_dumpSignals = false;     // main switch: --dump-signals
     bool m_emitAccessors = false;   // main switch: --emit-accessors
     bool m_exe = false;             // main switch: --exe
     bool m_flatten = false;         // main switch: --flatten
@@ -529,6 +530,7 @@ public:
     bool diagnosticsSarif() const VL_MT_SAFE { return m_diagnosticsSarif; }
     bool dpiHdrOnly() const { return m_dpiHdrOnly; }
     bool dumpDefines() const { return m_dumpLevel.count("defines") && m_dumpLevel.at("defines"); }
+    bool dumpSignals() const { return m_dumpSignals; }
     bool dumpTreeDot() const {
         return m_dumpLevel.count("tree-dot") && m_dumpLevel.at("tree-dot");
     }

src/Verilator.cpp

@@ -45,6 +45,7 @@
 #include "V3Descope.h"
 #include "V3DfgOptimizer.h"
 #include "V3DiagSarif.h"
+#include "V3DumpSignals.h"
 #include "V3EmitC.h"
 #include "V3EmitCMain.h"
 #include "V3EmitCMake.h"
@@ -153,6 +154,10 @@ static void process() {
             v3Global.vlExit(0);
         }
 
+        if (v3Global.opt.dumpSignals()) {
+            V3DumpSignals::dumpSignals(v3Global.rootp());
+        }
+
         // Instrument Design with the configurations given in .vlt file
         if (v3Global.opt.instrument()) {
             v3Global.dpi(true);