intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 188 insertions, 0 deletions

diff --git a/contrib/libs/llvm12/include/llvm/Support/CFGDiff.h b/contrib/libs/llvm12/include/llvm/Support/CFGDiff.h
new file mode 100644
index 00000000000..398314b4fce
--- /dev/null
+++ b/contrib/libs/llvm12/include/llvm/Support/CFGDiff.h
@@ -0,0 +1,188 @@
+#pragma once
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+
+//===- CFGDiff.h - Define a CFG snapshot. -----------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines specializations of GraphTraits that allows generic
+// algorithms to see a different snapshot of a CFG.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_CFGDIFF_H
+#define LLVM_SUPPORT_CFGDIFF_H
+
+#include "llvm/ADT/GraphTraits.h"
+#include "llvm/ADT/iterator.h"
+#include "llvm/ADT/iterator_range.h"
+#include "llvm/Support/CFGUpdate.h"
+#include "llvm/Support/type_traits.h"
+#include <cassert>
+#include <cstddef>
+#include <iterator>
+
+// Two booleans are used to define orders in graphs:
+// InverseGraph defines when we need to reverse the whole graph and is as such
+// also equivalent to applying updates in reverse.
+// InverseEdge defines whether we want to change the edges direction. E.g., for
+// a non-inversed graph, the children are naturally the successors when
+// InverseEdge is false and the predecessors when InverseEdge is true.
+
+namespace llvm {
+
+namespace detail {
+template <typename Range>
+auto reverse_if_helper(Range &&R, std::integral_constant<bool, false>) {
+  return std::forward<Range>(R);
+}
+
+template <typename Range>
+auto reverse_if_helper(Range &&R, std::integral_constant<bool, true>) {
+  return llvm::reverse(std::forward<Range>(R));
+}
+
+template <bool B, typename Range> auto reverse_if(Range &&R) {
+  return reverse_if_helper(std::forward<Range>(R),
+                           std::integral_constant<bool, B>{});
+}
+} // namespace detail
+
+// GraphDiff defines a CFG snapshot: given a set of Update<NodePtr>, provides
+// a getChildren method to get a Node's children based on the additional updates
+// in the snapshot. The current diff treats the CFG as a graph rather than a
+// multigraph. Added edges are pruned to be unique, and deleted edges will
+// remove all existing edges between two blocks.
+template <typename NodePtr, bool InverseGraph = false> class GraphDiff {
+  struct DeletesInserts {
+    SmallVector<NodePtr, 2> DI[2];
+  };
+  using UpdateMapType = SmallDenseMap<NodePtr, DeletesInserts>;
+  UpdateMapType Succ;
+  UpdateMapType Pred;
+
+  // By default, it is assumed that, given a CFG and a set of updates, we wish
+  // to apply these updates as given. If UpdatedAreReverseApplied is set, the
+  // updates will be applied in reverse: deleted edges are considered re-added
+  // and inserted edges are considered deleted when returning children.
+  bool UpdatedAreReverseApplied;
+
+  // Keep the list of legalized updates for a deterministic order of updates
+  // when using a GraphDiff for incremental updates in the DominatorTree.
+  // The list is kept in reverse to allow popping from end.
+  SmallVector<cfg::Update<NodePtr>, 4> LegalizedUpdates;
+
+  void printMap(raw_ostream &OS, const UpdateMapType &M) const {
+    StringRef DIText[2] = {"Delete", "Insert"};
+    for (auto Pair : M) {
+      for (unsigned IsInsert = 0; IsInsert <= 1; ++IsInsert) {
+        OS << DIText[IsInsert] << " edges: \n";
+        for (auto Child : Pair.second.DI[IsInsert]) {
+          OS << "(";
+          Pair.first->printAsOperand(OS, false);
+          OS << ", ";
+          Child->printAsOperand(OS, false);
+          OS << ") ";
+        }
+      }
+    }
+    OS << "\n";
+  }
+
+public:
+  GraphDiff() : UpdatedAreReverseApplied(false) {}
+  GraphDiff(ArrayRef<cfg::Update<NodePtr>> Updates,
+            bool ReverseApplyUpdates = false) {
+    cfg::LegalizeUpdates<NodePtr>(Updates, LegalizedUpdates, InverseGraph);
+    for (auto U : LegalizedUpdates) {
+      unsigned IsInsert =
+          (U.getKind() == cfg::UpdateKind::Insert) == !ReverseApplyUpdates;
+      Succ[U.getFrom()].DI[IsInsert].push_back(U.getTo());
+      Pred[U.getTo()].DI[IsInsert].push_back(U.getFrom());
+    }
+    UpdatedAreReverseApplied = ReverseApplyUpdates;
+  }
+
+  auto getLegalizedUpdates() const {
+    return make_range(LegalizedUpdates.begin(), LegalizedUpdates.end());
+  }
+
+  unsigned getNumLegalizedUpdates() const { return LegalizedUpdates.size(); }
+
+  cfg::Update<NodePtr> popUpdateForIncrementalUpdates() {
+    assert(!LegalizedUpdates.empty() && "No updates to apply!");
+    auto U = LegalizedUpdates.pop_back_val();
+    unsigned IsInsert =
+        (U.getKind() == cfg::UpdateKind::Insert) == !UpdatedAreReverseApplied;
+    auto &SuccDIList = Succ[U.getFrom()];
+    auto &SuccList = SuccDIList.DI[IsInsert];
+    assert(SuccList.back() == U.getTo());
+    SuccList.pop_back();
+    if (SuccList.empty() && SuccDIList.DI[!IsInsert].empty())
+      Succ.erase(U.getFrom());
+
+    auto &PredDIList = Pred[U.getTo()];
+    auto &PredList = PredDIList.DI[IsInsert];
+    assert(PredList.back() == U.getFrom());
+    PredList.pop_back();
+    if (PredList.empty() && PredDIList.DI[!IsInsert].empty())
+      Pred.erase(U.getTo());
+    return U;
+  }
+
+  using VectRet = SmallVector<NodePtr, 8>;
+  template <bool InverseEdge> VectRet getChildren(NodePtr N) const {
+    using DirectedNodeT =
+        std::conditional_t<InverseEdge, Inverse<NodePtr>, NodePtr>;
+    auto R = children<DirectedNodeT>(N);
+    VectRet Res = VectRet(detail::reverse_if<!InverseEdge>(R));
+
+    // Remove nullptr children for clang.
+    llvm::erase_value(Res, nullptr);
+
+    auto &Children = (InverseEdge != InverseGraph) ? Pred : Succ;
+    auto It = Children.find(N);
+    if (It == Children.end())
+      return Res;
+
+    // Remove children present in the CFG but not in the snapshot.
+    for (auto *Child : It->second.DI[0])
+      llvm::erase_value(Res, Child);
+
+    // Add children present in the snapshot for not in the real CFG.
+    auto &AddedChildren = It->second.DI[1];
+    llvm::append_range(Res, AddedChildren);
+
+    return Res;
+  }
+
+  void print(raw_ostream &OS) const {
+    OS << "===== GraphDiff: CFG edge changes to create a CFG snapshot. \n"
+          "===== (Note: notion of children/inverse_children depends on "
+          "the direction of edges and the graph.)\n";
+    OS << "Children to delete/insert:\n\t";
+    printMap(OS, Succ);
+    OS << "Inverse_children to delete/insert:\n\t";
+    printMap(OS, Pred);
+    OS << "\n";
+  }
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+  LLVM_DUMP_METHOD void dump() const { print(dbgs()); }
+#endif
+};
+} // end namespace llvm
+
+#endif // LLVM_SUPPORT_CFGDIFF_H
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif