From d1ee9827a00a4b415ddbaeeea4ebe6bb478ae095 Mon Sep 17 00:00:00 2001
From: Ryszard Rozak <rrozak@antmicro.com>
Date: Thu, 30 Nov 2023 14:32:12 +0100
Subject: [PATCH] Fix block names of nested do..while loops (#4728)

---
 src/V3LinkJump.cpp          | 19 ++++++++++---------
 test_regress/t/t_do_while.v |  9 +++++++++
 2 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/src/V3LinkJump.cpp b/src/V3LinkJump.cpp
index 235ffd7c5..bc3a2109f 100644
--- a/src/V3LinkJump.cpp
+++ b/src/V3LinkJump.cpp
@@ -142,18 +142,18 @@ class LinkJumpVisitor final : public VNVisitor {
             return labelp;
         }
     }
-    void addPrefixToBlocksRecurse(AstNode* nodep) {
-        // Add do_while_ prefix to blocks
+    void addPrefixToBlocksRecurse(const std::string& prefix, AstNode* const nodep) {
+        // Add a prefix to blocks
         // Used to not have blocks with duplicated names
         if (AstBegin* const beginp = VN_CAST(nodep, Begin)) {
-            if (beginp->name() != "") beginp->name("__Vdo_while_" + beginp->name());
+            if (beginp->name() != "") beginp->name(prefix + beginp->name());
         }
 
-        if (nodep->op1p()) addPrefixToBlocksRecurse(nodep->op1p());
-        if (nodep->op2p()) addPrefixToBlocksRecurse(nodep->op2p());
-        if (nodep->op3p()) addPrefixToBlocksRecurse(nodep->op3p());
-        if (nodep->op4p()) addPrefixToBlocksRecurse(nodep->op4p());
-        if (nodep->nextp()) addPrefixToBlocksRecurse(nodep->nextp());
+        if (nodep->op1p()) addPrefixToBlocksRecurse(prefix, nodep->op1p());
+        if (nodep->op2p()) addPrefixToBlocksRecurse(prefix, nodep->op2p());
+        if (nodep->op3p()) addPrefixToBlocksRecurse(prefix, nodep->op3p());
+        if (nodep->op4p()) addPrefixToBlocksRecurse(prefix, nodep->op4p());
+        if (nodep->nextp()) addPrefixToBlocksRecurse(prefix, nodep->nextp());
     }
 
     // VISITORS
@@ -240,7 +240,8 @@ class LinkJumpVisitor final : public VNVisitor {
         VL_DO_DANGLING(nodep->deleteTree(), nodep);
         if (bodyp) {
             AstNode* const copiedBodyp = bodyp->cloneTree(false);
-            addPrefixToBlocksRecurse(copiedBodyp);
+            addPrefixToBlocksRecurse("__Vdo_while1_", copiedBodyp);
+            addPrefixToBlocksRecurse("__Vdo_while2_", bodyp);
             whilep->addHereThisAsNext(copiedBodyp);
         }
     }
diff --git a/test_regress/t/t_do_while.v b/test_regress/t/t_do_while.v
index 9423853f4..cf52f432d 100644
--- a/test_regress/t/t_do_while.v
+++ b/test_regress/t/t_do_while.v
@@ -52,6 +52,15 @@ module t (/*AUTOARG*/);
       end while (a < 0);
       if (a != 5) $stop;
 
+      a = 1;
+      do begin
+         do begin
+            int x = 1;
+            a += x;
+         end while (a < 3);
+      end while (a < 5);
+      if (a != 5) $stop;
+
       $write("*-* All Finished *-*\n");
       $finish;
    end