From 06908165100304f642ce5b9c92aba5fe91837a91 Mon Sep 17 00:00:00 2001
From: yuchaojie <yuchaojie1@huawei.com>
Date: Sat, 8 May 2021 15:00:20 +0800
Subject: [PATCH] fix ub_fusion graph circle problem

---
 .../ascend/buffer_fusion/ub_pattern_fusion.cc | 36 +++++++++++--------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/mindspore/ccsrc/backend/optimizer/ascend/buffer_fusion/ub_pattern_fusion.cc b/mindspore/ccsrc/backend/optimizer/ascend/buffer_fusion/ub_pattern_fusion.cc
index f0b1e19d630..fad2df47b44 100644
--- a/mindspore/ccsrc/backend/optimizer/ascend/buffer_fusion/ub_pattern_fusion.cc
+++ b/mindspore/ccsrc/backend/optimizer/ascend/buffer_fusion/ub_pattern_fusion.cc
@@ -362,24 +362,28 @@ void SetFusionOpRefInfos(session::KernelGraph *kernel_graph, const std::vector<A
   }
 }
 
+bool CheckCircle(const session::KernelGraph &kernel_graph, const BufferFusionInfo_t &fusion_info) {
+  bool has_circle = false;
+  for (auto &inp : fusion_info.inputs_list) {
+    MS_EXCEPTION_IF_NULL(inp);
+    if (!inp->isa<CNode>() || AnfAlgo::CheckPrimitiveType(inp, prim::kPrimLoad)) {
+      continue;
+    }
+
+    if (IsDepend(kernel_graph, inp, fusion_info.anf_nodes)) {
+      has_circle = true;
+      break;
+    }
+  }
+  return has_circle;
+}
+
 void RemoveCircle(const session::KernelGraph &kernel_graph,
                   std::unordered_map<int64_t, BufferFusionInfo_t> *buffer_fusion_infos) {
   MS_EXCEPTION_IF_NULL(buffer_fusion_infos);
   std::vector<int64_t> fusion_ids;
   for (auto &[fusion_id, fusion_info] : *buffer_fusion_infos) {
-    bool has_circle = false;
-    for (auto &inp : fusion_info.inputs_list) {
-      MS_EXCEPTION_IF_NULL(inp);
-      if (!inp->isa<CNode>() || AnfAlgo::CheckPrimitiveType(inp, prim::kPrimLoad)) {
-        continue;
-      }
-
-      if (IsDepend(kernel_graph, inp, fusion_info.anf_nodes)) {
-        has_circle = true;
-        break;
-      }
-    }
-
+    bool has_circle = CheckCircle(kernel_graph, fusion_info);
     if (has_circle) {
       fusion_ids.emplace_back(fusion_id);
     }
@@ -440,7 +444,11 @@ bool UbPatternFusion::FuseBufferFusionPattern(session::KernelGraph *kernel_graph
       MS_LOG(DEBUG) << "fusion id: " << fusion_id << ", fusion op compiling failed";
       continue;
     }
-    change = ReplaceFusionOp(&buffer_fusion_infos, fusion_id, kernel_mods[fusion_id], kernel_graph);
+    if (CheckCircle(*kernel_graph, buffer_fusion_infos[fusion_id])) {
+      MS_LOG(DEBUG) << "fusion id: " << fusion_id << " will cause graph circle, pass this fusion.";
+    } else {
+      change = ReplaceFusionOp(&buffer_fusion_infos, fusion_id, kernel_mods[fusion_id], kernel_graph);
+    }
   }
   MS_LOG(DEBUG) << "End Buffer Fusion";
   return change;