Add extra triggers for virtual interfaces

Signed-off-by: Krzysztof Bieganski <[email protected]>

src/CMakeLists.txt

@@ -282,6 +282,7 @@ set(COMMON_SOURCES
     V3SchedPartition.cpp
     V3SchedReplicate.cpp
     V3SchedTiming.cpp
+    V3SchedVirtIface.cpp
     V3Scope.cpp
     V3Scoreboard.cpp
     V3Slice.cpp

src/Makefile_obj.in

@@ -274,6 +274,7 @@ RAW_OBJS_PCH_ASTNOMT = \
 	V3SchedPartition.o \
 	V3SchedReplicate.o \
 	V3SchedTiming.o \
+	V3SchedVirtIface.o \
 	V3Scope.o \
 	V3Scoreboard.o \
 	V3Slice.o \

src/V3AstNodeDType.h

@@ -834,6 +834,7 @@ class AstEnumDType final : public AstNodeDType {
 class AstIfaceRefDType final : public AstNodeDType {
     // Reference to an interface, either for a port, or inside parent cell
     // @astgen op1 := paramsp : List[AstPin]
+    bool m_virtual = false;  // True if virtual interface
     FileLine* m_modportFileline;  // Where modport token was
     string m_cellName;  // "" = no cell, such as when connects to 'input' iface
     string m_ifaceName;  // Interface name
@@ -876,6 +877,11 @@ class AstIfaceRefDType final : public AstNodeDType {
     bool similarDType(const AstNodeDType* samep) const override { return this == samep; }
     int widthAlignBytes() const override { return 1; }
     int widthTotalBytes() const override { return 1; }
+    void isVirtual(bool flag) {
+        m_virtual = flag;
+        if (flag) v3Global.setHasVirtIfaces();
+    }
+    bool isVirtual() const { return m_virtual; }
     FileLine* modportFileline() const { return m_modportFileline; }
     string cellName() const { return m_cellName; }
     void cellName(const string& name) { m_cellName = name; }

src/V3AstNodeOther.h

@@ -1727,6 +1727,7 @@ class AstVar final : public AstNode {
     VLifetime m_lifetime;  // Lifetime
     VVarAttrClocker m_attrClocker;
     MTaskIdSet m_mtaskIds;  // MTaskID's that read or write this var
+    AstIface* m_sensIfacep = nullptr;  // Interface type to which reads from this var are sensitive
     int m_pinNum = 0;  // For XML, if non-zero the connection pin number
     bool m_ansi : 1;  // Params or pins declared in the module header, rather than the body
     bool m_declTyped : 1;  // Declared as type (for dedup check)
@@ -1742,7 +1743,6 @@ class AstVar final : public AstNode {
     bool m_usedClock : 1;  // Signal used as a clock
     bool m_usedParam : 1;  // Parameter is referenced (on link; later signals not setup)
     bool m_usedLoopIdx : 1;  // Variable subject of for unrolling
-    bool m_usedVirtIface : 1;  // Signal used through a virtual interface
     bool m_funcLocal : 1;  // Local variable for a function
     bool m_funcLocalSticky : 1;  // As m_funcLocal but remains set if var is moved to a static
     bool m_funcReturn : 1;  // Return variable for a function
@@ -1784,7 +1784,6 @@ class AstVar final : public AstNode {
         m_usedClock = false;
         m_usedParam = false;
         m_usedLoopIdx = false;
-        m_usedVirtIface = false;
         m_sigPublic = false;
         m_sigModPublic = false;
         m_sigUserRdPublic = false;
@@ -1866,6 +1865,7 @@ class AstVar final : public AstNode {
         dtypeFrom(examplep);
     }
     ASTGEN_MEMBERS_AstVar;
+    void cloneRelink() override;
     void dump(std::ostream& str) const override;
     bool same(const AstNode* samep) const override;
     string name() const override VL_MT_STABLE VL_MT_SAFE { return m_name; }  // * = Var name
@@ -1913,6 +1913,7 @@ class AstVar final : public AstNode {
     }
     void ansi(bool flag) { m_ansi = flag; }
     void declTyped(bool flag) { m_declTyped = flag; }
+    void sensIfacep(AstIface* nodep) { m_sensIfacep = nodep; }
     void attrClocker(VVarAttrClocker flag) { m_attrClocker = flag; }
     void attrFileDescr(bool flag) { m_fileDescr = flag; }
     void attrScClocked(bool flag) { m_scClocked = flag; }
@@ -1923,7 +1924,6 @@ class AstVar final : public AstNode {
     void usedClock(bool flag) { m_usedClock = flag; }
     void usedParam(bool flag) { m_usedParam = flag; }
     void usedLoopIdx(bool flag) { m_usedLoopIdx = flag; }
-    void usedVirtIface(bool flag) { m_usedVirtIface = flag; }
     void sigPublic(bool flag) { m_sigPublic = flag; }
     void sigModPublic(bool flag) { m_sigModPublic = flag; }
     void sigUserRdPublic(bool flag) {
@@ -2016,7 +2016,6 @@ class AstVar final : public AstNode {
     bool isUsedClock() const { return m_usedClock; }
     bool isUsedParam() const { return m_usedParam; }
     bool isUsedLoopIdx() const { return m_usedLoopIdx; }
-    bool isUsedVirtIface() const { return m_usedVirtIface; }
     bool isSc() const VL_MT_SAFE { return m_sc; }
     bool isScQuad() const;
     bool isScBv() const;
@@ -2044,6 +2043,7 @@ class AstVar final : public AstNode {
     bool attrSFormat() const { return m_attrSFormat; }
     bool attrSplitVar() const { return m_attrSplitVar; }
     bool attrIsolateAssign() const { return m_attrIsolateAssign; }
+    AstIface* sensIfacep() const { return m_sensIfacep; }
     VVarAttrClocker attrClocker() const { return m_attrClocker; }
     string verilogKwd() const override;
     void lifetime(const VLifetime& flag) { m_lifetime = flag; }

src/V3AstNodes.cpp

@@ -2168,6 +2168,9 @@ int AstVarRef::instrCount() const {
     // Otherwise as a load/store
     return widthInstrs() * (access().isReadOrRW() ? INSTR_COUNT_LD : 1);
 }
+void AstVar::cloneRelink() {
+    if (m_sensIfacep && m_sensIfacep->clonep()) m_sensIfacep = m_sensIfacep->clonep();
+}
 void AstVar::dump(std::ostream& str) const {
     this->AstNode::dump(str);
     if (isSc()) str << " [SC]";

src/V3Const.cpp

@@ -2691,7 +2691,7 @@ class ConstVisitor final : public VNVisitor {
                      && m_doNConst
                      && v3Global.opt.fConst()
                      // Default value, not a "known" constant for this usage
-                     && !nodep->varp()->isClassMember() && !nodep->varp()->isUsedVirtIface()
+                     && !nodep->varp()->isClassMember() && !nodep->varp()->sensIfacep()
                      && !(nodep->varp()->isFuncLocal() && nodep->varp()->isNonOutput())
                      && !nodep->varp()->noSubst() && !nodep->varp()->isSigPublic())
                     || nodep->varp()->isParam())) {

src/V3Dead.cpp

@@ -361,7 +361,7 @@ class DeadVisitor final : public VNVisitor {
     }
     bool mightElimVar(AstVar* nodep) const {
         if (nodep->isSigPublic()) return false;  // Can't elim publics!
-        if (nodep->isIO() || nodep->isClassMember() || nodep->isUsedVirtIface()) return false;
+        if (nodep->isIO() || nodep->isClassMember() || nodep->sensIfacep()) return false;
         if (nodep->isTemp() && !nodep->isTrace()) return true;
         return m_elimUserVars;  // Post-Trace can kill most anything
     }

src/V3ExtraTriggerBuilder.h

@@ -0,0 +1,42 @@
+// -*- mode: C++; c-file-style: "cc-mode" -*-
+//*************************************************************************
+// DESCRIPTION: Verilator: Builder for sensitivity checking expressions.
+//
+// Code available from: https://verilator.org
+//
+//*************************************************************************
+//
+// Copyright 2003-2023 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_V3EXTRATRIGGERBUILDER_H_
+#define VERILATOR_V3EXTRATRIGGERBUILDER_H_
+
+#include "config_build.h"
+#include "verilatedos.h"
+
+#include "V3Ast.h"
+#include "V3UniqueNames.h"
+
+//######################################################################
+class ExtraTriggerBuilder final {
+    std::vector<string> m_descriptions;  // Human readable description of extra triggers
+
+public:
+    ExtraTriggerBuilder() = default;
+
+    size_t allocate(const string& description) {
+        const size_t index = m_descriptions.size();
+        m_descriptions.push_back(description);
+        return index;
+    }
+    size_t size() const { return m_descriptions.size(); }
+    const string& description(size_t index) const { return m_descriptions[index]; }
+};
+
+#endif  // Guard

src/V3Gate.cpp

@@ -163,7 +163,7 @@ class GateGraph final : public V3Graph {
             UINFO(6, "New vertex " << vscp << endl);
             vVtxp = new GateVarVertex{this, vscp};
             vscp->user1p(vVtxp);
-            if (vscp->varp()->isUsedVirtIface()) {
+            if (vscp->varp()->sensIfacep()) {
                 // Can be used in a class method, which cannot be tracked statically
                 vVtxp->clearReducibleAndDedupable("VirtIface");
                 vVtxp->setConsumed("VirtIface");

src/V3Global.h

@@ -112,6 +112,7 @@ class V3Global final {
     bool m_dpi = false;  // Need __Dpi include files
     bool m_hasEvents = false;  // Design uses SystemVerilog named events
     bool m_hasClasses = false;  // Design uses SystemVerilog classes
+    bool m_hasVirtIfaces = false;  // Design uses virtual interfaces
     bool m_usesProbDist = false;  // Uses $dist_*
     bool m_usesStdPackage = false;  // Design uses the std package
     bool m_usesTiming = false;  // Design uses timing constructs
@@ -162,6 +163,8 @@ class V3Global final {
     void setHasEvents() { m_hasEvents = true; }
     bool hasClasses() const { return m_hasClasses; }
     void setHasClasses() { m_hasClasses = true; }
+    bool hasVirtIfaces() const { return m_hasVirtIfaces; }
+    void setHasVirtIfaces() { m_hasVirtIfaces = true; }
     bool usesProbDist() const { return m_usesProbDist; }
     void setUsesProbDist() { m_usesProbDist = true; }
     bool usesStdPackage() const { return m_usesStdPackage; }

src/V3Life.cpp

@@ -137,7 +137,7 @@ class LifeBlock final {
     void checkRemoveAssign(const LifeMap::iterator& it) {
         const AstVar* const varp = it->first->varp();
         LifeVarEntry* const entp = &(it->second);
-        if (!varp->isSigPublic() && !varp->isUsedVirtIface()) {
+        if (!varp->isSigPublic() && !varp->sensIfacep()) {
             // Rather than track what sigs AstUCFunc/AstUCStmt may change,
             // we just don't optimize any public sigs
             // Check the var entry, and remove if appropriate
@@ -178,7 +178,7 @@ class LifeBlock final {
         const auto pair = m_map.emplace(nodep, LifeVarEntry::CONSUMED{});
         if (!pair.second) {
             if (AstConst* const constp = pair.first->second.constNodep()) {
-                if (!varrefp->varp()->isSigPublic() && !varrefp->varp()->isUsedVirtIface()) {
+                if (!varrefp->varp()->isSigPublic() && !varrefp->varp()->sensIfacep()) {
                     // Aha, variable is constant; substitute in.
                     // We'll later constant propagate
                     UINFO(4, "     replaceconst: " << varrefp << endl);

src/V3Localize.cpp

@@ -166,7 +166,7 @@ class LocalizeVisitor final : public VNVisitor {
             && !nodep->varp()->isFuncLocal()  // Not already a function local (e.g.: argument)
             && !nodep->varp()->isStatic()  // Not a static variable
             && !nodep->varp()->isClassMember()  // Statically exists in design hierarchy
-            && !nodep->varp()->isUsedVirtIface()  // Not used through a virtual interface
+            && !nodep->varp()->sensIfacep()  // Not sensitive to an interface
             && !nodep->varp()->valuep()  // Does not have an initializer
         ) {
             UINFO(4, "Consider for localization: " << nodep << endl);

src/V3Order.cpp

@@ -245,6 +245,11 @@ class OrderBuildVisitor final : public VNVisitor {
     void visit(AstNodeVarRef* nodep) override {
         // As we explicitly not visit (see ignored nodes below) any subtree that is not relevant
         // for ordering, we should be able to assert this:
+        if (!m_logicVxp) {
+            std::cout << nodep << endl;
+            nodep->backp()->dumpTree(cout);
+            nodep->backp()->backp()->dumpTree(cout);
+        }
         UASSERT_OBJ(m_scopep, nodep, "AstVarRef not under scope");
         UASSERT_OBJ(m_logicVxp, nodep, "AstVarRef not under logic");
         AstVarScope* const varscp = nodep->varScopep();