Add extra triggers for virtual interfaces

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

src/CMakeLists.txt

@@ -168,6 +168,7 @@ set(HEADERS
     V3Unknown.h
     V3Unroll.h
     V3VariableOrder.h
+    V3VirtIface.h
     V3Waiver.h
     V3Width.h
     V3WidthCommit.h
@@ -302,6 +303,7 @@ set(COMMON_SOURCES
     V3Undriven.cpp
     V3Unknown.cpp
     V3Unroll.cpp
+    V3VirtIface.cpp
     V3VariableOrder.cpp
     V3Waiver.cpp
     V3Width.cpp

src/Makefile_obj.in

@@ -291,6 +291,7 @@ RAW_OBJS_PCH_ASTNOMT = \
 	V3Undriven.o \
 	V3Unknown.o \
 	V3Unroll.o \
+	V3VirtIface.o \
 	V3VariableOrder.o \
 	V3Width.o \
 	V3WidthCommit.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 +877,8 @@ 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; }
+    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

@@ -1248,6 +1248,8 @@ class AstNetlist final : public AstNode {
     AstCFunc* m_evalp = nullptr;  // The '_eval' function
     AstCFunc* m_evalNbap = nullptr;  // The '_eval__nba' function
     AstVarScope* m_dpiExportTriggerp = nullptr;  // The DPI export trigger variable
+    using IfaceTriggerVec = std::vector<std::pair<const AstIface*, AstVarScope*>>;
+    IfaceTriggerVec m_virtIfaceTriggerps;  // The virtual interface trigger variables
     AstVar* m_delaySchedulerp = nullptr;  // The delay scheduler variable
     AstVarScope* m_nbaEventp = nullptr;  // The NBA event variable
     AstVarScope* m_nbaEventTriggerp = nullptr;  // If set to 1, the NBA event should get triggered
@@ -1278,6 +1280,7 @@ class AstNetlist final : public AstNode {
     void evalNbap(AstCFunc* funcp) { m_evalNbap = funcp; }
     AstVarScope* dpiExportTriggerp() const { return m_dpiExportTriggerp; }
     void dpiExportTriggerp(AstVarScope* varScopep) { m_dpiExportTriggerp = varScopep; }
+    IfaceTriggerVec& virtIfaceTriggerps() { return m_virtIfaceTriggerps; }
     AstVar* delaySchedulerp() const { return m_delaySchedulerp; }
     void delaySchedulerp(AstVar* const varScopep) { m_delaySchedulerp = varScopep; }
     AstVarScope* nbaEventp() const { return m_nbaEventp; }
@@ -1727,6 +1730,7 @@ 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 +1746,6 @@ 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 +1787,6 @@ 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;
@@ -1913,6 +1915,7 @@ 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 +1926,6 @@ 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 +2018,6 @@ 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 +2045,7 @@ 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

@@ -1950,6 +1950,7 @@ const char* AstNetlist::broken() const {
     BROKEN_RTN(m_delaySchedulerp && !m_delaySchedulerp->brokeExists());
     BROKEN_RTN(m_nbaEventp && !m_nbaEventp->brokeExists());
     BROKEN_RTN(m_nbaEventTriggerp && !m_nbaEventTriggerp->brokeExists());
+    for (const auto p : m_virtIfaceTriggerps) BROKEN_RTN(!p.second->brokeExists());
     return nullptr;
 }
 AstPackage* AstNetlist::dollarUnitPkgAddp() {

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/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/V3Sched.cpp

@@ -507,16 +507,16 @@ struct TriggerKit {
         m_funcp->stmtsp()->addHereThisAsNext(callp->makeStmt());
     }
 
-    // Utility to set then clear the dpiExportTrigger trigger
-    void addDpiExportTriggerAssignment(AstVarScope* dpiExportTriggerVscp, uint32_t index) const {
-        FileLine* const flp = dpiExportTriggerVscp->fileline();
+    // Utility to set then clear an extra trigger
+    void addExtraTriggerAssignment(AstVarScope* extraTriggerVscp, uint32_t index) const {
+        FileLine* const flp = extraTriggerVscp->fileline();
         AstVarRef* const vrefp = new AstVarRef{flp, m_vscp, VAccess::WRITE};
         AstCMethodHard* const callp = new AstCMethodHard{flp, vrefp, "set"};
         callp->addPinsp(new AstConst{flp, index});
-        callp->addPinsp(new AstVarRef{flp, dpiExportTriggerVscp, VAccess::READ});
+        callp->addPinsp(new AstVarRef{flp, extraTriggerVscp, VAccess::READ});
         callp->dtypeSetVoid();
         AstNode* const stmtp = callp->makeStmt();
-        stmtp->addNext(new AstAssign{flp, new AstVarRef{flp, dpiExportTriggerVscp, VAccess::WRITE},
+        stmtp->addNext(new AstAssign{flp, new AstVarRef{flp, extraTriggerVscp, VAccess::WRITE},
                                      new AstConst{flp, AstConst::BitFalse{}}});
         m_funcp->stmtsp()->addHereThisAsNext(stmtp);
     }
@@ -840,7 +840,7 @@ AstNode* createInputCombLoop(AstNetlist* netlistp, AstCFunc* const initFuncp,
         = createTriggers(netlistp, initFuncp, senExprBuilder, senTreeps, "ico", extraTriggers);
 
     if (dpiExportTriggerVscp) {
-        trig.addDpiExportTriggerAssignment(dpiExportTriggerVscp, dpiExportTriggerIndex);
+        trig.addExtraTriggerAssignment(dpiExportTriggerVscp, dpiExportTriggerIndex);
     }
 
     // Remap sensitivities
@@ -1156,6 +1156,10 @@ void schedule(AstNetlist* netlistp) {
     const size_t dpiExportTriggerIndex = dpiExportTriggerVscp
                                              ? extraTriggers.allocate("DPI export trigger")
                                              : std::numeric_limits<unsigned>::max();
+    const size_t firstVifTriggerIndex = dpiExportTriggerIndex + 1;
+    for (const auto p : netlistp->virtIfaceTriggerps()) {
+        const size_t vifTriggerIndex = extraTriggers.allocate(p.first->name());
+    }
 
     const auto& senTreeps = getSenTreesUsedBy({&logicRegions.m_pre,  //
                                                &logicRegions.m_act,  //
@@ -1170,7 +1174,14 @@ void schedule(AstNetlist* netlistp) {
     if (timingKit.m_postUpdates) actTrig.m_funcp->addStmtsp(timingKit.m_postUpdates);
 
     if (dpiExportTriggerVscp) {
-        actTrig.addDpiExportTriggerAssignment(dpiExportTriggerVscp, dpiExportTriggerIndex);
+        actTrig.addExtraTriggerAssignment(dpiExportTriggerVscp, dpiExportTriggerIndex);
+    }
+    {
+        size_t vifTriggerIndex = firstVifTriggerIndex;
+        for (const auto p : netlistp->virtIfaceTriggerps()) {
+            actTrig.addExtraTriggerAssignment(p.second, vifTriggerIndex);
+            vifTriggerIndex++;
+        }
     }
 
     AstVarScope* const actTrigVscp = actTrig.m_vscp;
@@ -1223,12 +1234,26 @@ void schedule(AstNetlist* netlistp) {
               ? createTriggerSenTree(netlistp, actTrig.m_vscp, dpiExportTriggerIndex)
               : nullptr;
 
+    std::map<const AstIface*, AstSenTree*> vifTriggeredAct;
+    {
+        size_t vifTriggerIndex = firstVifTriggerIndex;
+        for (const auto p : netlistp->virtIfaceTriggerps()) {
+            vifTriggeredAct.insert(std::make_pair(
+                p.first, createTriggerSenTree(netlistp, actTrig.m_vscp, vifTriggerIndex)));
+            vifTriggerIndex++;
+        }
+    }
+
     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) {
             auto it = actTimingDomains.find(vscp);
             if (it != actTimingDomains.end()) out = it->second;
             if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggeredAct);
+            if (vscp->varp()->sensIfacep()) {
+                const auto it = vifTriggeredAct.find(vscp->varp()->sensIfacep());
+                if (it != vifTriggeredAct.end()) out.push_back(it->second);
+            }
         });
     splitCheck(actFuncp);
     if (v3Global.opt.stats()) V3Stats::statsStage("sched-create-act");
@@ -1252,6 +1277,15 @@ void schedule(AstNetlist* netlistp) {
             = dpiExportTriggerVscp
                   ? createTriggerSenTree(netlistp, trigVscp, dpiExportTriggerIndex)
                   : nullptr;
+        std::map<const AstIface*, AstSenTree*> vifTriggered;
+        {
+            size_t vifTriggerIndex = firstVifTriggerIndex;
+            for (const auto p : netlistp->virtIfaceTriggerps()) {
+                vifTriggered.insert(std::make_pair(
+                    p.first, createTriggerSenTree(netlistp, trigVscp, vifTriggerIndex)));
+                vifTriggerIndex++;
+            }
+        }
 
         const auto& timingDomains = timingKit.remapDomains(trigMap);
         AstCFunc* const funcp = V3Order::order(
@@ -1260,6 +1294,10 @@ void schedule(AstNetlist* netlistp) {
                 auto it = timingDomains.find(vscp);
                 if (it != timingDomains.end()) out = it->second;
                 if (vscp->varp()->isWrittenByDpi()) out.push_back(dpiExportTriggered);
+                if (vscp->varp()->sensIfacep()) {
+                    const auto it = vifTriggered.find(vscp->varp()->sensIfacep());
+                    if (it != vifTriggered.end()) out.push_back(it->second);
+                }
             });
 
         // Create the trigger dumping function, which is the same as act trigger
@@ -1314,6 +1352,7 @@ void schedule(AstNetlist* netlistp) {
     splitCheck(initp);
 
     netlistp->dpiExportTriggerp(nullptr);
+    netlistp->virtIfaceTriggerps().clear();
 
     V3Global::dumpCheckGlobalTree("sched", 0, dumpTreeLevel() >= 3);
 }