Internals: More const. No functional change intended.

src/V3Active.cpp

@@ -299,7 +299,7 @@ private:
     // NODE STATE
     // Input:
     //  AstVar::user1p // V2LatchGraphVertex* The vertex handling this node
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
     // STATE
     LatchDetectGraph m_graph;  // Graph used to detect latches in combo always
     // VISITORS

src/V3ActiveTop.cpp

@@ -42,7 +42,7 @@ private:
     //   AstNode::user()                bool. True if processed
     //  Each call to V3Const::constify
     //   AstNode::user4()               Used by V3Const::constify, called below
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     SenTreeFinder m_finder;  // Find global sentree's / add them under the AstTopScope

src/V3Assert.cpp

@@ -30,7 +30,7 @@ private:
     // NODE STATE/TYPES
     // Cleared on netlist
     //  AstNode::user()         -> bool.  True if processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNodeModule* m_modp = nullptr;  // Last module

src/V3Begin.cpp

@@ -41,7 +41,7 @@ private:
     // NODE STATE
     // Entire netlist:
     // AstNodeFTask::user1      -> bool, 1=processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
     bool m_anyFuncInBegin = false;
 
 public:

src/V3Branch.cpp

@@ -40,7 +40,7 @@ private:
     // NODE STATE
     // Entire netlist:
     //  AstFTask::user1()       -> int.  Number of references
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     int m_likely = false;  // Excuses for branch likely taken

src/V3CUse.cpp

@@ -39,7 +39,7 @@
 class CUseVisitor final : public AstNVisitor {
     // NODE STATE
     //  AstNode::user1()     -> bool.  True if already visited
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // MEMBERS
     bool m_impOnly = false;  // In details needed only for implementation

src/V3Case.cpp

@@ -122,7 +122,7 @@ private:
     // NODE STATE
     // Cleared each Case
     //  AstIf::user3()          -> bool.  Set true to indicate clone not needed
-    AstUser3InUse m_inuser3;
+    const AstUser3InUse m_inuser3;
 
     // STATE
     VDouble0 m_statCaseFast;  // Statistic tracking

src/V3Cast.cpp

@@ -54,7 +54,7 @@ private:
     // NODE STATE
     // Entire netlist:
     //   AstNode::user()                // bool.  Indicates node is of known size
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
 
@@ -203,6 +203,6 @@ public:
 
 void V3Cast::castAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
-    { CastVisitor visitor{nodep}; }  // Destruct before checking
+    { const CastVisitor visitor{nodep}; }  // Destruct before checking
     V3Global::dumpCheckGlobalTree("cast", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }

src/V3Cdc.cpp

@@ -217,9 +217,9 @@ private:
     // AstVarScope::user2       -> bool  Used in sensitivity list
     // {statement}Node::user1p  -> CdcLogicVertex* for this statement
     // AstNode::user3           -> bool  True indicates to print %% (via V3EmitV)
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
 
     // STATE
     V3Graph m_graph;  // Scoreboard of var usages/dependencies

src/V3Changed.cpp

@@ -247,7 +247,7 @@ private:
     // NODE STATE
     // Entire netlist:
     //  AstVarScope::user1()            -> bool.  True indicates processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     ChangedState* m_statep;  // Shared state across visitors

src/V3Class.cpp

@@ -32,7 +32,7 @@
 class ClassVisitor final : public AstNVisitor {
 private:
     // MEMBERS
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
     string m_prefix;  // String prefix to add to name based on hier
     AstScope* m_classScopep = nullptr;  // Package moving scopes into
     AstScope* m_packageScopep = nullptr;  // Class package scope

src/V3Clean.cpp

@@ -42,9 +42,9 @@ private:
     //  AstNode::user()         -> CleanState.  For this node, 0==UNKNOWN
     //  AstNode::user2()        -> bool.  True indicates widthMin has been propagated
     //  AstNodeDType::user3()   -> AstNodeDType*.  Alternative node with C size
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
 
     // TYPES
     enum CleanState : uint8_t { CS_UNKNOWN, CS_CLEAN, CS_DIRTY };

src/V3Clock.cpp

@@ -73,7 +73,7 @@ private:
     // NODE STATE
     // Cleared each Module:
     //  AstVarScope::user1p()   -> AstVarScope*.  Temporary signal that was created.
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNodeModule* m_modp = nullptr;  // Current module

src/V3Combine.cpp

@@ -121,7 +121,7 @@ class CombineVisitor final : CombBaseVisitor {
 private:
     // NODE STATE
     // Entire netlist:
-    AstUser3InUse m_user3InUse;  // Marks replaced AstCFuncs
+    const AstUser3InUse m_user3InUse;  // Marks replaced AstCFuncs
     //  AstUser4InUse     part of V3Hasher in V3DupFinder
 
     // STATE

src/V3Common.cpp

@@ -109,7 +109,7 @@ void V3Common::commonAll() {
             // NODE STATE
             // Entire netlist:
             //  AstClass::user1()     -> bool.  True if class needs to_string dumper
-            AstUser1InUse m_inuser1;
+            const AstUser1InUse m_inuser1;
             // Create ToString methods
             makeVlToString(classp);
             makeToString(classp);

src/V3Const.cpp

@@ -110,7 +110,7 @@ class ConstBitOpTreeVisitor final : public AstNVisitor {
     // NODE STATE
     // AstVarRef::user4u      -> Base index of m_varInfos that points VarInfo
     // AstVarScope::user4u    -> Same as AstVarRef::user4
-    AstUser4InUse m_inuser4;
+    const AstUser4InUse m_inuser4;
 
     // TYPES
 
@@ -1975,7 +1975,7 @@ private:
             if (m_warn && !VN_IS(nodep, AssignDly)) {  // Is same var on LHS and RHS?
                 // Note only do this (need user4) when m_warn, which is
                 // done as unique visitor
-                AstUser4InUse m_inuser4;
+                const AstUser4InUse m_inuser4;
                 ConstVarMarkVisitor mark{nodep->lhsp()};
                 ConstVarFindVisitor find{nodep->rhsp()};
                 if (find.found()) need_temp = true;
@@ -2669,7 +2669,7 @@ private:
             // SENGATE(SENITEM(x)) -> SENITEM(x), then let it collapse with the
             // other SENITEM(x).
             {
-                AstUser4InUse m_inuse4;
+                const AstUser4InUse m_inuse4;
                 // Mark x in SENITEM(x)
                 for (AstSenItem* senp = nodep->sensesp(); senp;
                      senp = VN_AS(senp->nextp(), SenItem)) {

src/V3Coverage.cpp

@@ -73,7 +73,7 @@ private:
     // NODE STATE
     // Entire netlist:
     //  AstIf::user1()                  -> bool.  True indicates ifelse processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     CheckState m_state;  // State save-restored on each new coverage scope/block

src/V3Dead.cpp

@@ -76,7 +76,7 @@ private:
     //  AstVar::user1()         -> int. Count of number of references
     //  AstVarScope::user1()    -> int. Count of number of references
     //  AstNodeDType::user1()   -> int. Count of number of references
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // TYPES
     using AssignMap = std::multimap<AstVarScope*, AstNodeAssign*>;

src/V3Delayed.cpp

@@ -81,11 +81,11 @@ private:
     // Cleared each scope/active:
     //  AstAssignDly::user3()   -> AstVarScope*.  __Vdlyvset__ created for this assign
     //  AstAlwaysPost::user3()  -> AstVarScope*.  __Vdlyvset__ last referenced in IF
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
-    AstUser5InUse m_inuser5;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
+    const AstUser5InUse m_inuser5;
 
     // STATE
     AstActive* m_activep = nullptr;  // Current activate
@@ -512,6 +512,6 @@ public:
 
 void V3Delayed::delayedAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
-    { DelayedVisitor visitor{nodep}; }  // Destruct before checking
+    { const DelayedVisitor visitor{nodep}; }  // Destruct before checking
     V3Global::dumpCheckGlobalTree("delayed", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }

src/V3Descope.cpp

@@ -39,7 +39,7 @@ private:
     // NODE STATE
     //  Cleared entire netlist
     //   AstCFunc::user()               // bool.  Indicates processing completed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // TYPES
     using FuncMmap = std::multimap<std::string, AstCFunc*>;

src/V3EmitCBase.h

@@ -34,7 +34,7 @@ class EmitCParentModule final {
     // NODE STATE
     //   AstFunc::user4p()      AstNodeModule* Parent module pointer
     //   AstVar::user4p()       AstNodeModule* Parent module pointer
-    AstUser4InUse user4InUse;
+    const AstUser4InUse user4InUse;
 
 public:
     EmitCParentModule();

src/V3EmitCFunc.h

@@ -37,7 +37,7 @@ constexpr int EMITC_NUM_CONSTW = 8;
 class EmitCLazyDecls final : public AstNVisitor {
     // NODE STATE/TYPES
     //  AstNode::user2() -> bool. Already emitted decl for symbols.
-    AstUser2InUse m_inuser2;
+    const AstUser2InUse m_inuser2;
 
     // MEMBERS
     std::unordered_set<string> m_emittedManually;  // Set of names already declared manually.

src/V3EmitCImp.cpp

@@ -556,7 +556,7 @@ class EmitCTrace final : EmitCFunc {
     // NODE STATE/TYPES
     // Cleared on netlist
     //  AstNode::user1() -> int.  Enum number
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // MEMBERS
     const bool m_slow;  // Making slow file

src/V3EmitCSyms.cpp

@@ -34,7 +34,7 @@ class EmitCSyms final : EmitCBaseVisitor {
     // NODE STATE
     // Cleared on Netlist
     //  AstNodeModule::user1()  -> bool.  Set true __Vconfigure called
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // TYPES
     struct ScopeData {

src/V3Expand.cpp

@@ -42,7 +42,7 @@ class ExpandVisitor final : public AstNVisitor {
 private:
     // NODE STATE
     //  AstNode::user1()        -> bool.  Processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNode* m_stmtp = nullptr;  // Current statement

src/V3Gate.cpp

@@ -308,8 +308,8 @@ private:
     // AstVarScope::user2       -> bool: Signal used in SenItem in *this* always statement
     // AstVar::user2            -> bool: Warned about SYNCASYNCNET
     // AstNodeVarRef::user2     -> bool: ConcatOffset visited
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     V3Graph m_graph;  // Scoreboard of var usages/dependencies
@@ -907,9 +907,9 @@ private:
     //                     Set to nullptr if this assign's tree was later replaced
     // AstUser1InUse    m_inuser1;      (Allocated for use in GateVisitor)
     // AstUser2InUse    m_inuser2;      (Allocated for use in GateVisitor)
-    AstUser3InUse m_inuser3;
+    const AstUser3InUse m_inuser3;
     // AstUser4InUse    m_inuser4;      (Allocated for use in V3Hasher via V3DupFinder)
-    AstUser5InUse m_inuser5;
+    const AstUser5InUse m_inuser5;
 
     V3DupFinder m_dupFinder;  // Duplicate finder for rhs of assigns
     std::unordered_set<AstNode*> m_nodeDeleteds;  // Any node in this hash was deleted

src/V3GenClk.cpp

@@ -43,8 +43,8 @@ private:
     // Cleared on top scope
     //  AstVarScope::user2()    -> AstVarScope*.  Signal replacing activation with
     //  AstVarRef::user3()      -> bool.  Signal is replaced activation (already done)
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
 
     // STATE
     AstActive* m_activep = nullptr;  // Inside activate statement
@@ -141,7 +141,7 @@ private:
     // NODE STATE
     // Cleared on top scope
     //  AstVarScope::user()     -> bool.  Set when the var has been used as clock
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     bool m_tracingCall = false;  // Iterating into a call to a cfunc
@@ -231,6 +231,6 @@ public:
 
 void V3GenClk::genClkAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
-    { GenClkReadVisitor visitor{nodep}; }  // Destruct before checking
+    { const GenClkReadVisitor visitor{nodep}; }  // Destruct before checking
     V3Global::dumpCheckGlobalTree("genclk", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }

src/V3Global.cpp

@@ -46,7 +46,7 @@ void V3Global::checkTree() const { rootp()->checkTree(); }
 void V3Global::readFiles() {
     // NODE STATE
     //   AstNode::user4p()      // VSymEnt*    Package and typedef symbol names
-    AstUser4InUse inuser4;
+    const AstUser4InUse inuser4;
 
     VInFilter filter(v3Global.opt.pipeFilter());
     V3ParseSym parseSyms(v3Global.rootp());  // Symbol table must be common across all parsing

src/V3Hasher.h

@@ -32,7 +32,7 @@
 class V3Hasher final {
     // NODE STATE
     //  AstNode::user4()    -> V3Hash.  Hash value of this node (hash of 0 is illegal)
-    AstUser4InUse m_inuser4;
+    const AstUser4InUse m_inuser4;
 
 public:
     // CONSTRUCTORS

src/V3HierBlock.cpp

@@ -239,7 +239,7 @@ string V3HierBlock::commandArgsFileName(bool forCMake) const {
 class HierBlockUsageCollectVisitor final : public AstNVisitor {
     // NODE STATE
     // AstNode::user1()            -> bool. Processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     using ModuleSet = std::unordered_set<const AstModule*>;

src/V3Inline.cpp

@@ -53,9 +53,9 @@ private:
     //  AstNodeModule::user2()  // CIL_*. Allowed to automatically inline module
     //  AstNodeModule::user3()  // int. Number of cells referencing this module
     //  AstNodeModule::user4()  // int. Statements in module
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
 
     // For the user2 field:
     enum : uint8_t {
@@ -493,11 +493,10 @@ private:
     //                          // is a direct connect to
     //   AstVar::user3()        // bool    Don't alias the user2, keep it as signal
     //   AstCell::user4         // AstCell* of the created clone
-
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
-    AstUser5InUse m_inuser5;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
+    const AstUser5InUse m_inuser5;
 
     // STATE
     AstNodeModule* m_modp = nullptr;  // Current module
@@ -625,8 +624,7 @@ class InlineIntfRefVisitor final : public AstNVisitor {
 private:
     // NODE STATE
     //   AstVar::user1p()   // AstCell which this Var points to
-
-    AstUser2InUse m_inuser2;
+    const AstUser2InUse m_inuser2;
 
     string m_scope;  // Scope name
 
@@ -710,8 +708,8 @@ public:
 
 void V3Inline::inlineAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
-    AstUser1InUse m_inuser1;  // output of InlineMarkVisitor,
-                              // input to InlineVisitor.
+    const AstUser1InUse m_inuser1;  // output of InlineMarkVisitor,
+                                    // input to InlineVisitor.
     // Scoped to clean up temp userN's
     { InlineMarkVisitor mvisitor{nodep}; }
     { InlineVisitor visitor{nodep}; }

src/V3Inst.cpp

@@ -39,7 +39,7 @@ private:
     // NODE STATE
     // Cleared each Cell:
     //  AstPin::user1p()        -> bool.  True if created assignment already
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstCell* m_cellp = nullptr;  // Current cell

src/V3InstrCount.cpp

@@ -34,7 +34,7 @@ private:
     // NODE STATE
     //  AstNode::user4()        -> int.  Path cost + 1, 0 means don't dump
     //  AstNode::user5()        -> bool. Processed if assertNoDups
-    AstUser4InUse m_inuser4;
+    const AstUser4InUse m_inuser4;
 
     // MEMBERS
     uint32_t m_instrCount = 0;  // Running count of instructions

src/V3Life.cpp

@@ -41,7 +41,7 @@
 class LifeState final {
     // NODE STATE
     //   See below
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
 public:

src/V3LifePost.cpp

@@ -133,7 +133,7 @@ private:
     // NODE STATE
     // Cleared on entire tree
     //  AstVarScope::user4()    -> AstVarScope*: Passed to LifePostElim to substitute this var
-    AstUser4InUse m_inuser4;
+    const AstUser4InUse m_inuser4;
 
     // STATE
     uint32_t m_sequence = 0;  // Sequence number of assigns/varrefs,

src/V3LinkCells.cpp

@@ -101,8 +101,8 @@ private:
     //   AstCell::user2()               // bool   clone renaming completed
     //  Allocated across all readFiles in V3Global::readFiles:
     //   AstNode::user4p()      // VSymEnt*    Package and typedef symbol names
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     VInFilter* m_filterp;  // Parser filter

src/V3LinkDot.cpp

@@ -129,9 +129,9 @@ private:
     //  AstVar::user4()                 // bool.          True if port set for this variable
     //  AstNodeBlock::user4()           // bool.          Did name processing
     //  AstNodeModule::user4()          // bool.          Live module
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser4InUse m_inuser4;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser4InUse m_inuser4;
 
 public:
     // ENUMS
@@ -1783,8 +1783,8 @@ private:
     //  *::user4()              -> See LinkDotState
     // Cleared on Cell
     //  AstVar::user5()         // bool.          True if pin used in this cell
-    AstUser3InUse m_inuser3;
-    AstUser5InUse m_inuser5;
+    const AstUser3InUse m_inuser3;
+    const AstUser5InUse m_inuser5;
 
     // TYPES
     enum DotPosition : uint8_t {

src/V3LinkParse.cpp

@@ -40,8 +40,8 @@ private:
     // Cleared on netlist
     //  AstNode::user1()        -> bool.  True if processed
     //  AstNode::user2()        -> bool.  True if fileline recomputed
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // TYPES
     using ImplTypedefMap = std::map<const std::pair<void*, std::string>, AstTypedef*>;

src/V3LinkResolve.cpp

@@ -43,7 +43,7 @@ private:
     // NODE STATE
     //  Entire netlist:
     //   AstCaseItem::user2()   // bool           Moved default caseitems
-    AstUser2InUse m_inuser2;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     // Below state needs to be preserved between each module call.

src/V3Localize.cpp

@@ -45,10 +45,10 @@ private:
     //  AstVarScope::user3p()   ->  Set of CFuncs referencing this VarScope. (via m_accessors)
     //  AstCFunc::user4p()      ->  Multimap of 'VarScope -> VarRefs that reference that VarScope'
     //                              in this function. (via m_references)
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
 
     AstUser3Allocator<AstVarScope, std::unordered_set<AstCFunc*>> m_accessors;
     AstUser4Allocator<AstCFunc, std::unordered_multimap<const AstVarScope*, AstVarRef*>>

src/V3MergeCond.cpp

@@ -131,8 +131,8 @@ private:
     // NODE STATE
     // AstVar::user1        -> Flag set for variables referenced by m_mgCondp
     // AstNode::user2       -> Flag marking node as included in merge because cheap to duplicate
-    AstUser1InUse m_user1InUse;
-    AstUser2InUse m_user2InUse;
+    const AstUser1InUse m_user1InUse;
+    const AstUser2InUse m_user2InUse;
 
     // STATE
     VDouble0 m_statMerges;  // Statistic tracking

src/V3Name.cpp

@@ -37,7 +37,7 @@ private:
     //  AstCell::user1()        -> bool.  Set true if already processed
     //  AstScope::user1()       -> bool.  Set true if already processed
     //  AstVar::user1()         -> bool.  Set true if already processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNodeModule* m_modp = nullptr;

src/V3Order.cpp

@@ -364,8 +364,8 @@ class OrderBuildVisitor final : public AstNVisitor {
     // NODE STATE
     //  AstVarScope::user1    -> OrderUser instance for variable (via m_orderUser)
     //  AstVarScope::user2    -> VarUsage within logic blocks
-    AstUser1InUse user1InUse;
-    AstUser2InUse user2InUse;
+    const AstUser1InUse user1InUse;
+    const AstUser2InUse user2InUse;
     AstUser1Allocator<AstVarScope, OrderUser> m_orderUser;
 
     // STATE
@@ -1038,7 +1038,7 @@ class OrderProcess final : AstNDeleter {
     // NODE STATE
     //  AstNodeModule::user3  -> int: Number of AstCFuncs created under this module
     //  AstNode::user4        -> Used by V3Const::constifyExpensiveEdit
-    AstUser3InUse user3InUse;
+    const AstUser3InUse user3InUse;
 
     // STATE
     OrderGraph& m_graph;  // The ordering graph

src/V3Param.cpp

@@ -226,8 +226,8 @@ class ParamProcessor final {
     //   AstGenFor::user5()     // bool   True if processed
     //   AstVar::user5()        // bool   True if constant propagated
     //   AstCell::user5p()      // string* Generate portion of hierarchical name
-    AstUser4InUse m_inuser4;
-    AstUser5InUse m_inuser5;
+    const AstUser4InUse m_inuser4;
+    const AstUser5InUse m_inuser5;
     // User1/2/3 used by constant function simulations
 
     // TYPES

src/V3Partition.cpp

@@ -2566,7 +2566,7 @@ void V3Partition::go(V3Graph* mtasksp) {
     {
         // The V3InstrCount within LogicMTask will set user5 on each AST
         // node, to assert that we never count any node twice.
-        AstUser5InUse inUser5;
+        const AstUser5InUse inUser5;
         Vx2MTaskMap vx2mtask;
         for (V3GraphVertex* vxp = m_fineDepsGraphp->verticesBeginp(); vxp;
              vxp = vxp->verticesNextp()) {

src/V3Premit.cpp

@@ -44,7 +44,7 @@ class PremitAssignVisitor final : public AstNVisitor {
 private:
     // NODE STATE
     //  AstVar::user3()         // bool; occurs on LHS of current assignment
-    AstUser3InUse m_inuser3;
+    const AstUser3InUse m_inuser3;
 
     // STATE
     bool m_noopt = false;  // Disable optimization of variables in this block
@@ -93,8 +93,8 @@ private:
     //  AstShiftL::user2()      -> bool.  True if converted to conditional
     //  AstShiftR::user2()      -> bool.  True if converted to conditional
     //  *::user3()              -> See PremitAssignVisitor
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     AstCFunc* m_cfuncp = nullptr;  // Current block

src/V3Randomize.cpp

@@ -37,7 +37,7 @@ private:
     // NODE STATE
     // Cleared on Netlist
     //  AstClass::user1()       -> bool.  Set true to indicate needs randomize processing
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     using DerivedSet = std::unordered_set<AstClass*>;
     using BaseToDerivedMap = std::unordered_map<AstClass*, DerivedSet>;
@@ -119,7 +119,7 @@ private:
     //  AstClass::user1()       -> bool.  Set true to indicate needs randomize processing
     //  AstEnumDType::user2()   -> AstVar*.  Pointer to table with enum values
     // AstUser1InUse    m_inuser1;      (Allocated for use in RandomizeMarkVisitor)
-    AstUser2InUse m_inuser2;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     size_t m_enumValueTabCount = 0;  // Number of tables with enum values created

src/V3Reloop.cpp

@@ -45,7 +45,7 @@ class ReloopVisitor final : public AstNVisitor {
 private:
     // NODE STATE
     // AstCFunc::user1p      -> Var* for temp var, 0=not set yet
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     VDouble0 m_statReloops;  // Statistic tracking

src/V3Scope.cpp

@@ -41,8 +41,8 @@ private:
     // NODE STATE
     // AstVar::user1p           -> AstVarScope replacement for this variable
     // AstTask::user2p          -> AstTask*.  Replacement task
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // TYPES
     // These cannot be unordered unless make a specialized hashing pair (gcc-8)

src/V3Simulate.h

@@ -72,9 +72,9 @@ class SimulateVisitor VL_NOT_FINAL : public AstNVisitor {
 private:
     // NODE STATE
     // Cleared on each always/assignw
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
 
     // Checking:
     //  AstVar(Scope)::user1()  -> VarUsage.  Set true to indicate tracking as lvalue/rvalue

src/V3Slice.cpp

@@ -50,7 +50,7 @@ class SliceVisitor final : public AstNVisitor {
     //  AstNodeAssign::user1()      -> bool.  True if find is complete
     //  AstNodeUniop::user1()       -> bool.  True if find is complete
     //  AstArraySel::user1p()       -> AstVarRef. The VarRef that the final ArraySel points to
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNode* m_assignp = nullptr;  // Assignment we are under

src/V3Split.cpp

@@ -242,10 +242,10 @@ private:
     // AstVarScope::user2p      -> Var SplitNodeVertex* for delayed assignment var, 0=not set yet
     // Ast*::user3p             -> Statement SplitLogicVertex* (temporary only)
     // Ast*::user4              -> Current ordering number (reorderBlock usage)
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
 
 protected:
     // STATE

src/V3SplitAs.cpp

@@ -128,7 +128,7 @@ class SplitAsVisitor final : public SplitAsBaseVisitor {
 private:
     // NODE STATE
     //  AstAlways::user()       -> bool.  True if already processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     VDouble0 m_statSplits;  // Statistic tracking

src/V3SplitVar.cpp

@@ -127,7 +127,7 @@
 struct SplitVarImpl {
     // NODE STATE
     //  AstNodeModule::user1()  -> Block number counter for generating unique names
-    AstUser1InUse m_user1InUse;  // Only used in SplitUnpackedVarVisitor
+    const AstUser1InUse m_user1InUse;  // Only used in SplitUnpackedVarVisitor
 
     static AstNodeAssign* newAssign(FileLine* fileline, AstNode* lhsp, AstNode* rhsp,
                                     const AstVar* varp) {

src/V3Subst.cpp

@@ -227,8 +227,8 @@ private:
     // Passed to SubstUseVisitor
     // AstVar::user1p           -> SubstVar* for usage var, 0=not set yet
     // AstVar::user2            -> int step number for last assignment, 0=not set yet
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     std::vector<SubstVarEntry*> m_entryps;  // Nodes to delete when we are finished
@@ -381,6 +381,6 @@ public:
 
 void V3Subst::substituteAll(AstNetlist* nodep) {
     UINFO(2, __FUNCTION__ << ": " << endl);
-    { SubstVisitor visitor{nodep}; }  // Destruct before checking
+    { const SubstVisitor visitor{nodep}; }  // Destruct before checking
     V3Global::dumpCheckGlobalTree("subst", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
 }

src/V3Task.cpp

@@ -98,9 +98,8 @@ private:
     //   AstNodeFTask::user3p   // AstScope* this FTask is under
     //   AstNodeFTask::user4p   // GraphFTaskVertex* this FTask is under
     //   AstVar::user4p         // GraphFTaskVertex* this variable is declared in
-
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
 
     // TYPES
     using VarToScopeMap = std::map<std::pair<AstScope*, AstVar*>, AstVarScope*>;
@@ -370,7 +369,7 @@ struct TaskDpiUtils {
 class TaskGatherWrittenVisitor final : public AstNVisitor {
     // NODE STATE
     // AstVarScope::user5 -> Already considered variable
-    AstUser5InUse m_user5InUse;
+    const AstUser5InUse m_user5InUse;
 
     std::vector<AstVarScope*> m_writtenVariables;  // Variables written
 
@@ -408,9 +407,8 @@ private:
     // Each funccall
     //  to TaskRelinkVisitor:
     //    AstVar::user2p        // AstVarScope* to replace varref with
-
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // TYPES
     enum InsertMode : uint8_t {

src/V3Trace.cpp

@@ -162,9 +162,9 @@ private:
     //  AstVarScope::user1()            // V3GraphVertex* for this node
     //  AstCCall::user2()               // bool; walked next list for other ccalls
     //  Ast*::user3()                   // TraceActivityVertex* for this node
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
     // AstUser4InUse     In V3Hasher via V3DupFinder
 
     // STATE

src/V3Tristate.cpp

@@ -327,11 +327,11 @@ class TristateVisitor final : public TristateBaseVisitor {
     // See TristateGraph:
     //   AstVar::user5p         -> TristateVertex* for variable being built
     //   AstStmt*::user5p       -> TristateVertex* for this statement
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
-    AstUser3InUse m_inuser3;
-    AstUser4InUse m_inuser4;
-    AstUser5InUse m_inuser5;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
+    const AstUser3InUse m_inuser3;
+    const AstUser4InUse m_inuser4;
+    const AstUser5InUse m_inuser5;
 
     // TYPES
     using RefVec = std::vector<AstVarRef*>;

src/V3Undriven.cpp

@@ -240,10 +240,10 @@ private:
     // NODE STATE
     // Netlist:
     //  AstVar::user1p          -> UndrivenVar* for usage var, 0=not set yet
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
     // Each always:
     //  AstNode::user2p         -> UndrivenVar* for usage var, 0=not set yet
-    AstUser2InUse m_inuser2;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     std::array<std::vector<UndrivenVarEntry*>, 3> m_entryps;  // Nodes to delete when finished

src/V3Unknown.cpp

@@ -49,8 +49,8 @@ private:
     //  AstSel::user()          -> bool.  Set true if already processed
     //  AstArraySel::user()     -> bool.  Set true if already processed
     //  AstNode::user2p()       -> AstIf* Inserted if assignment for conditional
-    AstUser1InUse m_inuser1;
-    AstUser2InUse m_inuser2;
+    const AstUser1InUse m_inuser1;
+    const AstUser2InUse m_inuser2;
 
     // STATE
     AstNodeModule* m_modp = nullptr;  // Current module

src/V3VariableOrder.cpp

@@ -78,7 +78,7 @@ unsigned VarTspSorter::s_serialNext = 0;
 class VariableOrder final {
     // NODE STATE
     //  AstVar::user1()    -> attributes, via m_attributes
-    AstUser1InUse m_user1InUse;  // AstVar
+    const AstUser1InUse m_user1InUse;  // AstVar
 
     struct VarAttributes {
         uint32_t stratum;  // Roughly equivalent to alignment requirement, to avoid padding

src/V3WidthCommit.h

@@ -67,7 +67,7 @@ public:
 class WidthCommitVisitor final : public AstNVisitor {
     // NODE STATE
     // AstVar::user1p           -> bool, processed
-    AstUser1InUse m_inuser1;
+    const AstUser1InUse m_inuser1;
 
     // STATE
     AstNodeModule* m_modp = nullptr;