From 45abcb61074c7f0dec5b78005273efe8542cc224 Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Fri, 23 Dec 2022 16:17:08 -0500
Subject: [PATCH] Internals: Some V3LinkInc cleanups. No functional change.

---
 src/V3Const.cpp   |  7 ++++++-
 src/V3LinkInc.cpp | 23 ++++++++++-------------
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/src/V3Const.cpp b/src/V3Const.cpp
index b4a7d3f47..079527d46 100644
--- a/src/V3Const.cpp
+++ b/src/V3Const.cpp
@@ -3186,7 +3186,12 @@ private:
 
     void visit(AstStmtExpr* nodep) override {
         iterateChildren(nodep);
-        if (!nodep->exprp()) VL_DO_DANGLING(nodep->unlinkFrBack()->deleteTree(), nodep);
+        if (!nodep->exprp()) {
+            VL_DO_DANGLING(nodep->unlinkFrBack()->deleteTree(), nodep);
+            return;
+        }
+        // TODO if there's an ExprStmt underneath just keep lower statements
+        // (No current test case needs this)
     }
 
     // Simplify
diff --git a/src/V3LinkInc.cpp b/src/V3LinkInc.cpp
index c08b58f6a..6ef07750d 100644
--- a/src/V3LinkInc.cpp
+++ b/src/V3LinkInc.cpp
@@ -15,7 +15,7 @@
 //*************************************************************************
 // V3LinkInc's Transformations:
 //
-//      prepost_stmt_visit
+//      prepost_expr_visit
 //        PREADD/PRESUB
 //          Create a temporary __VIncrementX variable, assign the value of
 //          the current variable value to it, substitute the current
@@ -27,7 +27,7 @@
 //          Create a temporary __VIncrementX variable, assign the value of
 //          of the current variable (after the operation) to it. Substitute
 //          The original variable with the temporary one in the statement.
-//      prepost_non_stmt_visit
+//      prepost_stmt_visit
 //        PREADD/PRESUB/POSTADD/POSTSUB
 //          Increment/decrement the current variable by the given value.
 //          The order (pre/post) doesn't matter outside statements thus
@@ -193,36 +193,33 @@ private:
     void prepost_visit(AstNodeTriop* nodep) {
         // Check if we are underneath a statement
         if (!m_insStmtp) {
-            prepost_non_stmt_visit(nodep);
-        } else {
             prepost_stmt_visit(nodep);
+        } else {
+            prepost_expr_visit(nodep);
         }
     }
-    void prepost_non_stmt_visit(AstNodeTriop* nodep) {
+    void prepost_stmt_visit(AstNodeTriop* nodep) {
         iterateChildren(nodep);
 
         AstConst* const constp = VN_AS(nodep->lhsp(), Const);
         UASSERT_OBJ(nodep, constp, "Expecting CONST");
         AstConst* const newconstp = constp->cloneTree(true);
 
-        AstNodeExpr* const storetop = nodep->thsp();
-        AstNodeExpr* const valuep = nodep->rhsp();
-
-        storetop->unlinkFrBack();
-        valuep->unlinkFrBack();
+        AstNodeExpr* const storeTop = nodep->thsp()->unlinkFrBack();
+        AstNodeExpr* const valuep = nodep->rhsp()->unlinkFrBack();
 
         AstAssign* assignp;
         if (VN_IS(nodep, PreSub) || VN_IS(nodep, PostSub)) {
-            assignp = new AstAssign{nodep->fileline(), storetop,
+            assignp = new AstAssign{nodep->fileline(), storeTop,
                                     new AstSub{nodep->fileline(), valuep, newconstp}};
         } else {
-            assignp = new AstAssign{nodep->fileline(), storetop,
+            assignp = new AstAssign{nodep->fileline(), storeTop,
                                     new AstAdd{nodep->fileline(), valuep, newconstp}};
         }
         nodep->replaceWith(assignp);
         VL_DO_DANGLING(nodep->deleteTree(), nodep);
     }
-    void prepost_stmt_visit(AstNodeTriop* nodep) {
+    void prepost_expr_visit(AstNodeTriop* nodep) {
         iterateChildren(nodep);
 
         const AstNodeVarRef* varrefp = nullptr;