fix double sb from fifo rotations during intra coissue

1 files changed, 11 insertions, 0 deletions

diff --git a/src/abstract_hardware_model.h b/src/abstract_hardware_model.h
index 09d59f9..8d1e0e8 100644
--- a/src/abstract_hardware_model.h
+++ b/src/abstract_hardware_model.h
@@ -1934,6 +1934,16 @@ class simt_tables {
     return m_simt_splits_table->move_split_to_front(split_id);
   }
 
+  // Mode 2 (slot-pinned scoreboard) cross-slot drain gate. Set by
+  // simt_tables::update() when the FIFO membership changes due to actual
+  // divergence (num_divergent_paths > 1) or reconvergence (active mask
+  // grows on RPC merge). NOT set by co-issue's move_split_to_front
+  // (FIFO ordering change without membership change). Cleared by the
+  // fetch-stage gate once both slot scoreboards are observed clean.
+  bool div_recv_drain_pending() const { return m_div_recv_drain_pending; }
+  void set_div_recv_drain_pending() { m_div_recv_drain_pending = true; }
+  void clear_div_recv_drain_pending() { m_div_recv_drain_pending = false; }
+
  private:
   unsigned m_warp_id;
   unsigned m_warp_size;
@@ -1942,6 +1952,7 @@ class simt_tables {
   const shader_core_config *m_config;
   const struct memory_config *m_mem_config;
   shader_core_ctx *m_shader;
+  bool m_div_recv_drain_pending = false;
 };
 
 // ── End ITS data structures ─────────────────────────────────────────────────