Internals: Add VL_DO_DANGLING in some missing places. No functional change intended.

src/V3AssertNfa.cpp

@@ -1839,7 +1839,7 @@ class SvaNfaLowering final {
         };
         UASSERT_OBJ(size > 0, idxExprp, "Ring size must be positive");
         if (size == 1) {
-            idxExprp->deleteTree();
+            VL_DO_DANGLING(idxExprp->deleteTree(), idxExprp);
             return u32Const(0);
         }
         // idx == size - 1 ? 0 : idx + 1

src/V3AssertPre.cpp

@@ -1549,7 +1549,7 @@ private:
                                  "Unsupported: $sampled inside disabled condition of a sequence");
                 m_disablep = new AstConst{m_disablep->fileline(), AstConst::BitFalse{}};
                 // always a copy is used, so remove it now
-                pushDeletep(m_disablep);
+                pushDeletep(m_disablep);  // m_disablep used later
             }
             FileLine* const flp = nodep->fileline();
             // Add counter which counts times the condition turned true
@@ -1587,7 +1587,7 @@ private:
                 = new AstIf{flp, new AstEq{flp, new AstVarRef{flp, initialCntp, VAccess::READ},
                                            readCntRefp->cloneTree(false)}};
             // Delete it, because it is always copied before insetion to the AST
-            pushDeletep(m_disableSeqIfp);
+            pushDeletep(m_disableSeqIfp);  // m_disableSeqIfp used later
         }
         iterateChildren(nodep);
     }

src/V3Clock.cpp

@@ -97,7 +97,7 @@ class ClockVisitor final : public VNVisitor {
         VL_DO_DANGLING(nodep->deleteTree(), nodep);
     }
     void visit(AstSenTree* nodep) override {
-        pushDeletep(nodep->unlinkFrBack());  // No longer needed
+        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);  // No longer needed
     }
 
     //========== Move sampled assignments

src/V3Coverage.cpp

@@ -1053,7 +1053,7 @@ class CoverageVisitor final : public VNVisitor {
                 unrolledp = new T_Oper{fl, selp, unrolledp};
             }
             iterate(unrolledp);
-            pushDeletep(unrolledp);
+            VL_DO_DANGLING(pushDeletep(unrolledp), unrolledp);
         } else {
             iterateChildren(nodep);
             lineTrack(nodep);

src/V3Covergroup.cpp

@@ -3011,7 +3011,7 @@ class FunctionalCoverageVisitor final : public VNVisitor {
                     bindp->add(" = &");
                     bindp->add(rhsp->unlinkFrBack());
                     assignp->replaceWith(bindp->makeStmt());
-                    pushDeletep(assignp);
+                    VL_DO_DANGLING(pushDeletep(assignp), assignp);
                     ++rewrittenBindings;
                 }
             }

src/V3Delayed.cpp

@@ -820,7 +820,7 @@ class DelayedVisitor final : public VNVisitor {
         m_prevVscp = vscp;
 
         // Delete original NBA
-        pushDeletep(nodep->unlinkFrBack());
+        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
     }
 
     // Scheme::FlagUnique
@@ -870,7 +870,7 @@ class DelayedVisitor final : public VNVisitor {
         ifp->addThensp(new AstAssign{flp, capturedLhsp, capturedRhsp});
 
         // Delete original NBA
-        pushDeletep(nodep->unlinkFrBack());
+        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
     }
 
     // Scheme::ValueQueuePartial/Scheme::ValueQueueWhole
@@ -1020,7 +1020,7 @@ class DelayedVisitor final : public VNVisitor {
         nodep->addHereThisAsNext(callp->makeStmt());
 
         // Delete original NBA
-        pushDeletep(nodep->unlinkFrBack());
+        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
     }
 
     // Record where a variable is assigned

src/V3Force.cpp

@@ -1605,12 +1605,12 @@ static void assignAllImpl(AstNetlist* nodep, ForceState::ForceHelperVarsByVar& h
         assignp->replaceWith(new AstAssignForce{assignp->fileline(),
                                                 assignp->lhsp()->unlinkFrBack(),
                                                 assignp->rhsp()->unlinkFrBack()});
-        assignp->deleteTree();
+        VL_DO_DANGLING(assignp->deleteTree(), assignp);
     }
     for (AstDeassign* const deassignp : deassignps) {
         deassignp->replaceWith(
             new AstRelease{deassignp->fileline(), deassignp->lhsp()->cloneTreePure(true)});
-        deassignp->deleteTree();
+        VL_DO_DANGLING(deassignp->deleteTree(), deassignp);
     }
     ForceState state{true, helperVars, permanentlyProtected, forceRdUpdateBuilt};
     { ForceDiscoveryVisitor{nodep, state}; }

src/V3Inst.cpp

@@ -639,7 +639,7 @@ private:
                 }
                 if (prevp) {
                     pinVarp->replaceWith(prevp);
-                    pushDeletep(pinVarp);
+                    VL_DO_DANGLING(pushDeletep(pinVarp), pinVarp);
                 }
                 nodep->replaceWith(prevPinp);
                 VL_DO_DANGLING(pushDeletep(nodep), nodep);
@@ -713,7 +713,7 @@ private:
             }
             if (prevp) {
                 pinVarp->replaceWith(prevp);
-                pushDeletep(pinVarp);
+                VL_DO_DANGLING(pushDeletep(pinVarp), pinVarp);
             }  // else pinVarp already unlinked when another instance did this step
             nodep->replaceWith(prevPinp);
             VL_DO_DANGLING(pushDeletep(nodep), nodep);

src/V3LinkDot.cpp

@@ -2076,7 +2076,7 @@ class LinkDotFindVisitor final : public VNVisitor {
                         AstNodeDType* const oldDtp = nodep->childDTypep();
 
                         oldDtp->replaceWith(newDtp->cloneTree(false));
-                        oldDtp->deleteTree();
+                        VL_DO_DANGLING(oldDtp->deleteTree(), oldDtp);
                     }
                 }
             }
@@ -2781,7 +2781,7 @@ private:
             }
         }
         iterateChildren(nodep);
-        pushDeletep(nodep->unlinkFrBack());
+        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
     }
     void visit(AstAliasScope* nodep) override {  // ScopeVisitor::
         // Defer AliasScope processing - must process outer scopes before inner ones
@@ -6364,7 +6364,8 @@ class LinkDotResolveVisitor final : public VNVisitor {
                 nodep->v3warn(E_UNSUPPORTED, "Node of type "
                                                  << nodep->targetRefp()->prettyTypeName()
                                                  << " referenced by disable");
-                pushDeletep(nodep->unlinkFrBack());
+                VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
+                return;
             }
             if (nodep->targetp()) {
                 nodep->targetRefp()->unlinkFrBack()->deleteTree();

src/V3LinkWith.cpp

@@ -116,7 +116,7 @@ class LinkWithVisitor final : public VNVisitor {
             AstNodeExpr* const newp
                 = new AstLambdaArgRef{prevFromp->fileline(), prevFromp->name(), false};
             prevFromp->replaceWith(newp);
-            pushDeletep(prevFromp);
+            VL_DO_DANGLING(pushDeletep(prevFromp), prevFromp);
         }
         iterateChildren(nodep);
     }

src/V3Localize.cpp

@@ -104,7 +104,7 @@ class LocalizeVisitor final : public VNVisitor {
 
             // Yank the VarScope from it's parent and schedule them for deletion. Leave the Var
             // for now, as not all VarScopes referencing this Var might be localized.
-            pushDeletep(nodep->unlinkFrBack());
+            pushDeletep(nodep->unlinkFrBack());  // TODO nodep used past here
 
             // In each referencing function, create a replacement local variable
             AstVar* const oldVarp = nodep->varp();

src/V3Param.cpp

@@ -1209,7 +1209,7 @@ class ParamProcessor final {
         if (constp && !constp->num().isString()) {
             constp->replaceWith(
                 new AstConst{constp->fileline(), AstConst::String{}, constp->num().toString()});
-            constp->deleteTree();
+            VL_DO_DANGLING(constp->deleteTree(), constp);
         }
     }
 
@@ -2113,7 +2113,7 @@ class ParamProcessor final {
                 // It is a temporary copy of the original class node, stored in order to create
                 // another instances. It is needed only during class instantiation.
                 UINFO(8, "    Created clone " << nodeCopyp);
-                m_deleter.pushDeletep(nodeCopyp);
+                m_deleter.pushDeletep(nodeCopyp);  // nodeCopyp used past here
                 srcModp->user3p(nodeCopyp);
                 storeOriginalParams(nodeCopyp);
             }
@@ -2155,7 +2155,7 @@ class ParamProcessor final {
         genericInterfaceVarSetup(paramsp, pinsp);
 
         // Delete the parameters from the cell; they're not relevant any longer.
-        if (paramsp) paramsp->unlinkFrBackWithNext()->deleteTree();
+        if (paramsp) VL_DO_DANGLING(paramsp->unlinkFrBackWithNext()->deleteTree(), paramsp);
         return newModp;
     }
 

src/V3ParseImp.cpp

@@ -102,7 +102,7 @@ AstNodeExpr* V3ParseImp::makePropertyCase(FileLine* flp, AstNodeExpr* exprp, Ast
 
     if (!itemsp) {
         flp->v3error("Property case statement with no items");
-        exprp->deleteTree();
+        VL_DO_DANGLING(exprp->deleteTree(), exprp);
         return new AstConst{flp, AstConst::BitTrue{}};
     }
 
@@ -113,7 +113,7 @@ AstNodeExpr* V3ParseImp::makePropertyCase(FileLine* flp, AstNodeExpr* exprp, Ast
         if (itemp->isDefault()) {
             if (defaultPropp) {
                 itemp->v3error("Multiple default statements in property case statement");
-                defaultPropp->deleteTree();
+                VL_DO_DANGLING(defaultPropp->deleteTree(), defaultPropp);
                 exprp->deleteTree();
                 return new AstConst{flp, AstConst::BitTrue{}};
             }
@@ -140,11 +140,11 @@ AstNodeExpr* V3ParseImp::makePropertyCase(FileLine* flp, AstNodeExpr* exprp, Ast
         resultp = resultp ? new AstSAnd{flp, resultp, branchp, /*propertyControl=*/true} : branchp;
         matchedp = matchedp ? new AstLogOr{itemp->fileline(), matchedp, itemMatchp} : itemMatchp;
     }
-    itemsp->deleteTree();
+    VL_DO_DANGLING(itemsp->deleteTree(), itemsp);
 
     if (defaultPropp) {
         if (!matchedp) {
-            exprp->deleteTree();
+            VL_DO_DANGLING(exprp->deleteTree(), exprp);
             return defaultPropp;
         }
         AstNodeExpr* const noMatchp
@@ -152,8 +152,8 @@ AstNodeExpr* V3ParseImp::makePropertyCase(FileLine* flp, AstNodeExpr* exprp, Ast
         AstNodeExpr* const branchp = new AstImplication{defaultFlp, noMatchp, defaultPropp, true};
         resultp = new AstSAnd{flp, resultp, branchp, /*propertyControl=*/true};
     }
-    matchedp->deleteTree();
-    exprp->deleteTree();
+    VL_DO_DANGLING(matchedp->deleteTree(), matchedp);
+    VL_DO_DANGLING(exprp->deleteTree(), exprp);
     return resultp;
 }
 

src/V3Randomize.cpp

@@ -866,7 +866,8 @@ class ConstraintExprVisitor final : public VNVisitor {
             , m_firstExpressionInsideIndexPointerp{pointerToFirstExprp} {}
         ~NestedAccessPath() {
             if (m_nestedNameFormatp) {
-                m_nestedNameFormatTopp->deleteTree();
+                VL_DO_CLEAR(m_nestedNameFormatTopp->deleteTree(),
+                            m_nestedNameFormatTopp = nullptr);
                 m_nestedNameFormatp = nullptr;
             }
         }
@@ -2621,7 +2622,7 @@ class ConstraintExprVisitor final : public VNVisitor {
         if (!genVarp) {
             // This shall be substituted with an assert when it will be supported
             nodep->v3warn(CONSTRAINTIGN, "Unsupported: Unique constraint in randomize() with {}");
-            pushDeletep(nodep->unlinkFrBack());
+            VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
             return;
         }
         if (m_classp) {
@@ -3494,7 +3495,7 @@ class CaptureVisitor final : public VNVisitor {
                 = new AstVarRef{nodep->fileline(), newVarp, VAccess::READ};
             notXVarRefp->classOrPackagep(nodep->classOrPackagep());
             nodep->replaceWith(notXVarRefp);
-            nodep->deleteTree();
+            VL_DO_DANGLING(nodep->deleteTree(), nodep);
             nodep = notXVarRefp;
         }
         m_ignore.emplace(nodep);
@@ -4884,7 +4885,7 @@ class RandomizeVisitor final : public VNVisitor {
             }
             if (appendStmtp) newStmtp->addNext(appendStmtp);
             m_stmtp->replaceWith(newStmtp);
-            pushDeletep(m_stmtp);
+            VL_DO_CLEAR(pushDeletep(m_stmtp), m_stmtp = nullptr);
         } else {
             UASSERT_OBJ(receiverp, ftaskRefp, "Should have receiver");
             UASSERT_OBJ(!appendStmtp, ftaskRefp, "Append path requires arg-form rand_mode");
@@ -4995,7 +4996,7 @@ class RandomizeVisitor final : public VNVisitor {
                     = AstNode::addNext(setStmtsp, new AstAssign{fl, setp, new AstConst{fl, 1}});
                 exprp = getFromp(exprp);
             }
-            argp->unlinkFrBack()->deleteTree();
+            VL_DO_DANGLING(argp->unlinkFrBack()->deleteTree(), argp);
         }
         if (hasNullArg) {  // Re-point to the per-class __Vrandomize_null wrapper
             AstClass* targetClassp = nullptr;
@@ -6104,7 +6105,7 @@ class RandomizeVisitor final : public VNVisitor {
                             "Per-instance rand_mode var missing without static fallback");
                 UASSERT_OBJ(VN_IS(nodep->backp(), StmtExpr), nodep, "Should be a statement");
                 m_stmtp->replaceWith(classLevelStaticLoopp);
-                pushDeletep(m_stmtp);
+                VL_DO_CLEAR(pushDeletep(m_stmtp), m_stmtp = nullptr);
                 return;
             }
             AstNodeExpr* const lhsp = makeModeAssignLhs(nodep->fileline(), randModeTarget.classp,

src/V3Sched.cpp

@@ -581,7 +581,8 @@ void createIcoRegion(AstNetlist* netlistp, AstCFunc* const initFuncp,
         util::callVoidFunc(icoFuncp));
 
     // Release temporary input change detect SenTrees
-    for (AstSenTree* const senTreep : icoChangeSenTreeps) senTreep->deleteTree();
+    for (AstSenTree* const senTreep : icoChangeSenTreeps)
+        VL_DO_DANGLING(senTreep->deleteTree(), senTreep);
     icoChangeSenTreeps.clear();
 }
 

src/V3Sched.h

@@ -112,7 +112,7 @@ struct LogicByScope final : public std::vector<std::pair<AstScope*, AstActive*>>
                 }
             }
             if (activep->backp()) activep->unlinkFrBack();
-            activep->deleteTree();
+            VL_DO_DANGLING(activep->deleteTree(), activep);
         }
         clear();
     };

src/V3SplitVar.cpp

@@ -760,7 +760,7 @@ class SplitUnpackedVarVisitor final : public VNVisitor, public SplitVarImpl {
                 varp->attrSplitVar(!cannotSplitPackedVarReason(varp));
                 m_forPackedSplit.m_refs[m_modp].add(varp);
             } else {
-                pushDeletep(varp->unlinkFrBack());
+                VL_DO_DANGLING(pushDeletep(varp->unlinkFrBack()), varp);
             }
             ++numSplit;
         }

src/V3Task.cpp

@@ -596,7 +596,7 @@ class TaskVisitor final : public VNVisitor {
                 m_scopep->addVarsp(newvscp);
                 AstVarRef* const repp = new AstVarRef{pinp->fileline(), newvscp, VAccess::WRITE};
                 pinp->replaceWith(repp);
-                pushDeletep(pinp);
+                VL_DO_DANGLING(pushDeletep(pinp), pinp);
                 pinp = repp;
             }
             if (inlineTask) {

src/V3Trace.cpp

@@ -355,7 +355,7 @@ class TraceVisitor final : public VNVisitor {
                             } while (emptyScope);
                         }
                         // Can't purge until we finish this pass
-                        pushDeletep(declp->unlinkFrBack());
+                        pushDeletep(declp->unlinkFrBack());  // declp used below
                         vvertexp->rerouteEdges(&m_graph);
                         vvertexp->unlinkDelete(&m_graph);
                     }
@@ -1137,8 +1137,7 @@ class TraceVisitor final : public VNVisitor {
         // TraceInc
         for (const auto& i : traces) {
             AstNode* const valuep = i.second->nodep()->valuep();
-            valuep->unlinkFrBack();
-            valuep->deleteTree();
+            VL_DO_DANGLING(valuep->unlinkFrBack()->deleteTree(), valuep);
         }
 
         // Create the trace cleanup function clearing the activity flags

src/V3Tristate.cpp

@@ -1974,8 +1974,7 @@ class TristateVisitor final : public TristateBaseVisitor {
                     }
                     newp = new AstAdd{nodep->fileline(), nodep, newp};
                 } else {
-                    // TODO: looks dubious that we still iterate this below...
-                    pushDeletep(nodep);
+                    pushDeletep(nodep);  // TODO: looks dubious that we still iterate this below...
                 }
                 UINFOTREE(9, newp, "", "countout");
                 relinkHandle.relink(newp);

src/V3Udp.cpp

@@ -139,8 +139,8 @@ class UdpVisitor final : public VNVisitor {
                 } else if (valName == "x" || valName == "X") {
                     // No x inputs supported yet, so this whole table line
                     // can never match. Drop the whole thing.
-                    if (edgetrigp) pushDeletep(edgetrigp);
-                    if (logandp) pushDeletep(logandp);
+                    if (edgetrigp) VL_DO_DANGLING(pushDeletep(edgetrigp), edgetrigp);
+                    if (logandp) VL_DO_DANGLING(pushDeletep(logandp), logandp);
                     return;
                 }
             }
@@ -157,8 +157,8 @@ class UdpVisitor final : public VNVisitor {
 
         string const oValName = nodep->udpIsCombo() ? oNodep->name() : oNodep->nextp()->name();
         if (oValName == "-") {
-            if (edgetrigp) pushDeletep(edgetrigp);
-            if (logandp) pushDeletep(logandp);
+            if (edgetrigp) VL_DO_DANGLING(pushDeletep(edgetrigp), edgetrigp);
+            if (logandp) VL_DO_DANGLING(pushDeletep(logandp), logandp);
             return;
         }
 
@@ -173,8 +173,8 @@ class UdpVisitor final : public VNVisitor {
             } else if (oNodep->name() == "x" || oNodep->name() == "X") {
                 // No x inputs supported yet, so this whole table line
                 // can never match. Drop the whole thing.
-                if (edgetrigp) pushDeletep(edgetrigp);
-                if (logandp) pushDeletep(logandp);
+                if (edgetrigp) VL_DO_DANGLING(pushDeletep(edgetrigp), edgetrigp);
+                if (logandp) VL_DO_DANGLING(pushDeletep(logandp), logandp);
                 return;
             }
         }
@@ -189,7 +189,7 @@ class UdpVisitor final : public VNVisitor {
                 oNodep->v3error("Illegal value for combinational UDP line output");
             }
             m_alwaysBlockp->addStmtsp(ifp);
-            if (edgetrigp) pushDeletep(edgetrigp);
+            if (edgetrigp) VL_DO_DANGLING(pushDeletep(edgetrigp), edgetrigp);
             return;
         }
         if (!isSequentOutputSig(oValName)) {

src/V3Unknown.cpp

@@ -126,7 +126,7 @@ class UnknownVisitor final : public VNVisitor {
                 addVar(varp);
                 AstNode* const prepCopyp = prep->clonep();
                 prepCopyp->replaceWith(new AstVarRef{fl, varp, VAccess::WRITE});
-                pushDeletep(prepCopyp);
+                VL_DO_DANGLING(pushDeletep(prepCopyp), prepCopyp);
             }
             AstIf* const newp = new AstIf{fl, condp, origStmtp, elseStmtp};
             replaceHandle.relink(newp);

src/V3Unroll.cpp

@@ -186,7 +186,7 @@ class UnrollOneVisitor final : VNVisitor {
                 if (AstLoopTest* const testp = VN_CAST(nodep, LoopTest)) {
                     foundLoopTest = true;
                     // Will not actually need it, nor any subsequent
-                    pushDeletep(testp);
+                    pushDeletep(testp);  // TODO testp used past here
                     // Loop continues - add rest of statements
                     if (testp->condp()->isNeqZero()) continue;
                     // Won't need any of the trailing statements

src/V3Width.cpp

@@ -1782,7 +1782,7 @@ class WidthVisitor final : public VNVisitor {
             }
         }
         if (!newp) {
-            pushDeletep(nodep->unlinkFrBack());
+            VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
             return;
         }
         nodep->replaceWith(new AstAlways{newp});
@@ -2316,7 +2316,7 @@ class WidthVisitor final : public VNVisitor {
     // Delete a subtree after removing any saved references that point into it.
     static void deleteTreeCaptured(AstNode* nodep) {
         V3LinkDotIfaceCapture::purgeDeletedSubtree(nodep);
-        nodep->deleteTree();
+        VL_DO_DANGLING(nodep->deleteTree(), nodep);
     }
     void visit(AstAttrOf* nodep) override {
         VL_RESTORER(m_attrp);
@@ -2477,7 +2477,7 @@ class WidthVisitor final : public VNVisitor {
             AstNodeDType* const declDtp = [&]() {
                 if (m_ftaskp->fvarp()) return m_ftaskp->fvarp()->dtypep();
                 AstNodeDType* const voidp = new AstVoidDType{m_ftaskp->fileline()};
-                pushDeletep(voidp);
+                pushDeletep(voidp);  // Note voidp used past here
                 return voidp;
             }();
             if (!similarDTypeRecurse(protoDtp, declDtp)) {
@@ -5854,9 +5854,9 @@ class WidthVisitor final : public VNVisitor {
                 AstPatMember* patp = nullptr;
                 if (it == patmap.end()) {  // Default or default_type assignment
                     patp = defaultPatp_patternUOrStruct(nodep, memp, vdtypep, defaultp, dtypemap);
-                    pushDeletep(patp);
+                    pushDeletep(patp);  // patp used below
                     patp = defaultPatp_forDType(patp, memp->virtRefDTypep(), dtypemap);
-                    pushDeletep(patp);
+                    pushDeletep(patp);  // patp used below
                 } else {
                     patp = it->second;  // Member assignment
                 }
@@ -6868,7 +6868,7 @@ class WidthVisitor final : public VNVisitor {
             nodep->foreach([this](AstScopeName* nodep) {  //
                 nodep->replaceWith(
                     new AstConst{nodep->fileline(), AstConst::String{}, "<scope-unavailable>"});
-                pushDeletep(nodep);
+                VL_DO_DANGLING(pushDeletep(nodep), nodep);
             });
             V3Const::constifyParamsEdit(nodep->fmtp());  // fmtp may change
             string text = VString::dequotePercent(nodep->fmtp()->text());