!9312 Refactor and simplify the inlining procedure.

From: @zh_qh
Reviewed-by: 
Signed-off-by:

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

@@ -70,46 +70,21 @@ class ReplaceApplicator : public AnfVisitor {
   }
 };
 
-using CriterionFuncType = std::function<bool(FuncGraphPtr, AnfNodePtr)>;
+class InlinerBase;
+using CriterionFuncType = std::function<bool(InlinerBase *, const FuncGraphPtr &, const AnfNodePtr &)>;
 
-bool IsTrivial(const FuncGraphPtr &fg, AnfNodePtr) {
-  auto n_cnode = fg->nodes().size() - fg->parameters().size();
-  // There is at least one CNode(return, other_node).
-  return n_cnode <= 2;
-}
-
-bool IsUniqueUse(const FuncGraphPtr &fg, AnfNodePtr) {
-  auto &cnodes = fg->func_graph_cnodes_index();
-  int64_t n_use = std::accumulate(
-    cnodes.begin(), cnodes.end(), 0,
-    [](int64_t sum, const std::pair<const CNodeIndexPairPtr, int64_t> &item) { return sum + item.second; });
-  return n_use == 1;
-}
-
-bool IsInside(FuncGraphPtr, const AnfNodePtr &node) {
-  MS_EXCEPTION_IF_NULL(node->func_graph());
-  return node->func_graph()->has_flag("inline_inside");
-}
-
-bool IsCore(const FuncGraphPtr &fg, AnfNodePtr) { return fg->has_flag("core"); }
-
-bool NoCriterion(FuncGraphPtr, AnfNodePtr) { return true; }
+bool IsUniqueUse(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &);
 
-bool IsDirectParentCall(FuncGraphPtr fg, AnfNodePtr node) {
-  bool unique_use = IsUniqueUse(fg, nullptr);
-  bool is_recursive = fg->recursive();
-  if (fg->parent() != nullptr && is_recursive) {
-    if (fg->parent() == node->func_graph() && unique_use) {
-      return true;
-    }
-  }
-  return false;
-}
+bool IsTrivial(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &);
+bool IsInside(InlinerBase *, const FuncGraphPtr &, const AnfNodePtr &node);
+bool IsCore(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &);
+bool IsDirectParentCall(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &node);
+bool IsNotRecursive(InlinerBase *inliner, const FuncGraphPtr &fg, const AnfNodePtr &);
 
 // {G, Xs}
 class InlinerBase : public AnfVisitor {
  public:
-  explicit InlinerBase(std::vector<std::pair<CriterionFuncType, bool>> criterions, bool use_move = true)
+  explicit InlinerBase(std::vector<std::vector<CriterionFuncType>> criterions, bool use_move = true)
       : use_move_(use_move), criterions_(criterions) {}
   ~InlinerBase() override = default;
   AnfNodePtr operator()(const OptimizerPtr &, const AnfNodePtr &node) override {
@@ -135,22 +110,24 @@ class InlinerBase : public AnfVisitor {
         return nullptr;
       }
     }
-
     Reset();
+
+    // 'criterions_': {criterion_group_1:{criterion1, criterion2, ...}, criterion_group_2:{...}, ...}
+    // All the criterions of 'criterion group' are true would set 'criterion group' as 'true'. As [AND].
+    // Anyone of 'criterion group' in 'criterions_' is 'true' would be matched. As [OR].
     bool is_match = false;
-    for (auto &criterion : criterions_) {
-      if (!criterion.first(fg, node)) {
-        continue;
+    for (auto &criterions : criterions_) {  // Each 'criterion group' in criterions_.
+      is_match = true;
+      for (auto &criterion : criterions) {  // Each criterion in 'criterion group'.
+        if (!criterion(this, fg, node)) {
+          is_match = false;
+          break;
+        }
       }
-
-      if (criterion.second && IsRecursive(fg)) {
-        continue;
+      if (is_match) {
+        break;
       }
-
-      is_match = true;
-      break;
     }
-
     if (!is_match) {
       return nullptr;
     }
@@ -162,24 +139,19 @@ class InlinerBase : public AnfVisitor {
     if (fg->parameters().size() != args.size()) {
       return nullptr;
     }
-    auto is_unique_use = IsUniqueUse(fg, nullptr);
-    // Not to inline after block if it has switch call inside, to avoid switch expansion.
-    if (!is_unique_use && fg->has_flag(FUNC_GRAPH_FLAG_AFTER_BLOCK)) {
-      auto has_branch_call = GraphHasBranch(fg);
-      if (has_branch_call) {
-        return TransformBranchCall(fg, node, args);
+    if (IsUniqueUse(nullptr, fg, nullptr)) {
+      if (use_move_) {
+        auto mng = fg->manager();
+        MS_EXCEPTION_IF_NULL(mng);
+        ReplaceParams(mng, args, fg);
+        auto out_node = fg->output();
+        mng->MoveAllCNodeDropGraph(fg, node->func_graph(), inputs[0]->scope());
+        return out_node;
       }
+    } else if (fg->has_flag(FUNC_GRAPH_FLAG_AFTER_BLOCK) && GraphHasBranch(fg)) {
+      // Not to inline after block if it has switch call inside, to avoid switch expansion.
+      return TransformBranchCall(fg, node, args);
     }
-
-    if (use_move_ && is_unique_use) {
-      auto mng = fg->manager();
-      MS_EXCEPTION_IF_NULL(mng);
-      ReplaceParams(mng, args, fg);
-      auto out_node = fg->output();
-      mng->MoveAllCNodeDropGraph(fg, node->func_graph(), inputs[0]->scope());
-      return out_node;
-    }
-
     return InlineClone(fg, node->func_graph(), args, inputs[0]->scope());
   }
 
@@ -208,6 +180,7 @@ class InlinerBase : public AnfVisitor {
     is_checked_ = false;
     is_recursive_ = false;
   }
+
   // For after block which contains branch call, delete the parameters which is not used.
   // In most cases, it may be a `Module` or other constant input.
   AnfNodePtr TransformBranchCall(const FuncGraphPtr &fg, const AnfNodePtr &node, const std::vector<AnfNodePtr> &args) {
@@ -298,25 +271,62 @@ class InlinerBase : public AnfVisitor {
  private:
   bool is_checked_{false}, is_recursive_{false};
   bool use_move_;
-  std::vector<std::pair<CriterionFuncType, bool>> criterions_;
+  std::vector<std::vector<CriterionFuncType>> criterions_;
   std::unordered_map<FuncGraphPtr, bool> graph_branch_cache_;
   // Key is the old func graph, and the value is the new func_graph
   std::unordered_map<FuncGraphPtr, FuncGraphPtr> transformed_branch_chache_;
 };
 
+bool IsUniqueUse(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &) {
+  auto &cnodes = fg->func_graph_cnodes_index();
+  int64_t n_use = std::accumulate(
+    cnodes.begin(), cnodes.end(), 0,
+    [](int64_t sum, const std::pair<const CNodeIndexPairPtr, int64_t> &item) { return sum + item.second; });
+  return n_use == 1;
+}
+
+bool IsTrivial(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &) {
+  auto n_cnode = fg->nodes().size() - fg->parameters().size();
+  // There is at least one CNode(return, other_node).
+  return n_cnode <= 2;
+}
+
+bool IsInside(InlinerBase *, const FuncGraphPtr &, const AnfNodePtr &node) {
+  MS_EXCEPTION_IF_NULL(node->func_graph());
+  return node->func_graph()->has_flag("inline_inside");
+}
+
+bool IsCore(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &) { return fg->has_flag("core"); }
+
+bool IsDirectParentCall(InlinerBase *, const FuncGraphPtr &fg, const AnfNodePtr &node) {
+  bool unique_use = IsUniqueUse(nullptr, fg, nullptr);
+  bool is_recursive = fg->recursive();
+  if (fg->parent() != nullptr && is_recursive) {
+    if (fg->parent() == node->func_graph() && unique_use) {
+      return true;
+    }
+  }
+  return false;
+}
+
+bool IsNotRecursive(InlinerBase *inliner, const FuncGraphPtr &fg, const AnfNodePtr &) {
+  return !inliner->IsRecursive(fg);
+}
+
 class Inliner : public InlinerBase {
  public:
   explicit Inliner(bool use_move = true)
       : InlinerBase(
+          // Supports AND conditions in one criterion, Ex. {IsUniqueUse, IsNotRecursive}.
           {
-            {IsUniqueUse, true},
-            {IsTrivial, false},
-            {IsInside, false},
-            {IsCore, false},
-            {IsDirectParentCall, false},
-            {NoCriterion, true},
+            {IsTrivial},
+            {IsInside},
+            {IsCore},
+            {IsNotRecursive},
+            {IsDirectParentCall},
           },
           use_move) {}
+
   ~Inliner() override = default;
 };
 
@@ -324,8 +334,9 @@ class DirectInliner : public InlinerBase {
  public:
   explicit DirectInliner(bool use_move = true)
       : InlinerBase(
+          // Supports AND conditions in one criterion, Ex. {IsUniqueUse, IsNotRecursive}.
           {
-            {IsDirectParentCall, false},
+            {IsDirectParentCall},
           },
           use_move) {}
   ~DirectInliner() override = default;