From a5f4d40901389d560d1366582670350ffe4e27cd Mon Sep 17 00:00:00 2001
From: Artur Bieniek <abieniek@antmicro.com>
Date: Mon, 6 Jul 2026 19:13:11 +0200
Subject: [PATCH] Fix range delays with parameter bounds (#7882)

Signed-off-by: Artur Bieniek <abieniek@antmicro.com>
---
 src/V3AssertNfa.cpp                           |  4 ++--
 src/V3Width.cpp                               | 11 +++++++++++
 test_regress/t/t_property_sexpr_range_delay.v |  7 +++++++
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/V3AssertNfa.cpp b/src/V3AssertNfa.cpp
index f01e0da62..b96696cff 100644
--- a/src/V3AssertNfa.cpp
+++ b/src/V3AssertNfa.cpp
@@ -472,8 +472,8 @@ class SvaNfaBuilder final {
     AstVar* tryHoistSampled(AstNodeExpr* exprp, FileLine* flp, int cloneCount) {
         constexpr int kHoistThreshold = 2;
         if (cloneCount < kHoistThreshold) return nullptr;
-        AstVar* const tempVarp = new AstVar{flp, VVarType::MODULETEMP, m_propTempNames.get(exprp),
-                                            m_modp->findBitDType()};
+        AstVar* const tempVarp
+            = new AstVar{flp, VVarType::MODULETEMP, m_propTempNames.get(exprp), exprp->dtypep()};
         m_modp->addStmtsp(tempVarp);
         AstAssign* const assignp = new AstAssign{flp, new AstVarRef{flp, tempVarp, VAccess::WRITE},
                                                  sampled(exprp->cloneTreePure(false))};
diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index acc20248d..802fe155d 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -731,6 +731,17 @@ class WidthVisitor final : public VNVisitor {
         iterateCheckBool(nodep, "default disable iff condition", nodep->condp(), BOTH);
     }
     void visit(AstDelay* nodep) override {
+        if (nodep->isCycleDelay() && m_underSExpr) {
+            // Fold parameterized SVA cycle-delay bounds
+            userIterateAndNext(nodep->lhsp(), WidthVP{SELF, BOTH}.p());
+            V3Const::constifyParamsNoWarnEdit(nodep->lhsp());
+            if (nodep->rhsp() && !nodep->isUnbounded()) {
+                // Fold parametrized SVA cycle-delay max bound
+                userIterateAndNext(nodep->rhsp(), WidthVP{SELF, BOTH}.p());
+                V3Const::constifyParamsNoWarnEdit(nodep->rhsp());
+            }
+            return;
+        }
         if (AstNodeExpr* const fallDelayp = nodep->fallDelay()) {
             iterateCheckDelay(nodep, "delay", nodep->lhsp(), BOTH);
             iterateCheckDelay(nodep, "delay", fallDelayp, BOTH);
diff --git a/test_regress/t/t_property_sexpr_range_delay.v b/test_regress/t/t_property_sexpr_range_delay.v
index cd3037d03..85ad2dcc8 100644
--- a/test_regress/t/t_property_sexpr_range_delay.v
+++ b/test_regress/t/t_property_sexpr_range_delay.v
@@ -13,6 +13,8 @@
 module t (
     input clk
 );
+  parameter P = 1;
+
   integer cyc = 0;
   reg [63:0] crc = '0;
   reg [63:0] sum = '0;
@@ -64,6 +66,11 @@ module t (
   assert property (@(posedge clk) disable iff (cyc < 2)
       a |-> ##[1:3] (a | b | c | d | e));
 
+  // Parameterized range bound
+  assert property (@(posedge clk) disable iff (cyc < 2)
+      a |-> ##[P:P+3] (a | b | c | d | e));
+  assert property (@(posedge clk) ##[P:P+3] 1);
+
   // ##[2:4] range delay
   assert property (@(posedge clk) disable iff (cyc < 2)
       b |-> ##[2:4] (a | b | c | d | e));