!8049 [ME][OptPass]fix bug when eliminate tuple getitem after switch

Merge pull request !8049 from chenfei_mindspore/fix-bug-of-corporate-switch-pass

mindspore/ccsrc/frontend/optimizer/irpass/incorporate_getitem.h

@@ -22,6 +22,7 @@
 #include <unordered_map>
 #include <unordered_set>
 #include <vector>
+#include <utility>
 
 #include "ir/func_graph.h"
 #include "ir/func_graph_cloner.h"
@@ -372,7 +373,11 @@ class IncorporateGetitemSwitch : public AnfVisitor {
     if (g2_ == nullptr) {
       return nullptr;
     }
-
+    auto tuple_getitem = node->cast<CNodePtr>();
+    MS_EXCEPTION_IF_NULL(tuple_getitem);
+    if (MultipleUseOfSwitch(tuple_getitem->input(1), fg)) {
+      return nullptr;
+    }
     auto new_g1 = getitem_transform_(g1_, idx_);
     auto new_g2 = getitem_transform_(g2_, idx_);
     auto sw_node = fg->NewCNode({NewValueNode(prim::kPrimSwitch), x_, NewValueNode(new_g1), NewValueNode(new_g2)});
@@ -423,6 +428,24 @@ class IncorporateGetitemSwitch : public AnfVisitor {
   }
 
  private:
+  bool MultipleUseOfSwitch(const AnfNodePtr &switch_call, const FuncGraphPtr &fg) const {
+    auto switch_call_cnode = switch_call->cast<CNodePtr>();
+    MS_EXCEPTION_IF_NULL(switch_call_cnode);
+    auto manager = fg->manager();
+    MS_EXCEPTION_IF_NULL(manager);
+    auto node_users_map = manager->node_users();
+    auto it = node_users_map.find(switch_call);
+    if (it == node_users_map.end()) {
+      return false;
+    }
+    auto node_users = it->second;
+    // If switch was used by more than 1 tuple_getitem nodes, this pass shouldn't be execute.s
+    auto tuple_getitem_num = std::count_if(node_users.begin(), node_users.end(), [](std::pair<AnfNodePtr, int> &user) {
+      return IsPrimitiveCNode(user.first, prim::kPrimTupleGetItem);
+    });
+    return tuple_getitem_num > 1;
+  }
+
   int idx_{-1};
   AnfNodePtr switch_{nullptr}, x_{nullptr};
   FuncGraphPtr g1_{nullptr}, g2_{nullptr};