build(antlr): 引入第三方 ANTLR4 runtime/tool 并接入构建

third_party/antlr4-runtime-4.13.2/runtime/src/atn/LexerActionExecutor.cpp

@@ -0,0 +1,108 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#include "misc/MurmurHash.h"
+#include "atn/LexerIndexedCustomAction.h"
+#include "atn/HashUtils.h"
+#include "support/CPPUtils.h"
+#include "support/Arrays.h"
+#include "support/Casts.h"
+
+#include "atn/LexerActionExecutor.h"
+
+using namespace antlr4;
+using namespace antlr4::atn;
+using namespace antlr4::misc;
+using namespace antlrcpp;
+
+namespace {
+
+  bool lexerActionEqual(const Ref<const LexerAction> &lhs, const Ref<const LexerAction> &rhs) {
+    return *lhs == *rhs;
+  }
+
+}
+
+LexerActionExecutor::LexerActionExecutor(std::vector<Ref<const LexerAction>> lexerActions)
+    : _lexerActions(std::move(lexerActions)), _hashCode(0) {}
+
+Ref<const LexerActionExecutor> LexerActionExecutor::append(const Ref<const LexerActionExecutor> &lexerActionExecutor,
+                                                           Ref<const LexerAction> lexerAction) {
+  if (lexerActionExecutor == nullptr) {
+    return std::make_shared<LexerActionExecutor>(std::vector<Ref<const LexerAction>>{ std::move(lexerAction) });
+  }
+  std::vector<Ref<const LexerAction>> lexerActions;
+  lexerActions.reserve(lexerActionExecutor->_lexerActions.size() + 1);
+  lexerActions.insert(lexerActions.begin(), lexerActionExecutor->_lexerActions.begin(), lexerActionExecutor->_lexerActions.end());
+  lexerActions.push_back(std::move(lexerAction));
+  return std::make_shared<LexerActionExecutor>(std::move(lexerActions));
+}
+
+Ref<const LexerActionExecutor> LexerActionExecutor::fixOffsetBeforeMatch(int offset) const {
+  std::vector<Ref<const LexerAction>> updatedLexerActions;
+  for (size_t i = 0; i < _lexerActions.size(); i++) {
+    if (_lexerActions[i]->isPositionDependent() && !LexerIndexedCustomAction::is(*_lexerActions[i])) {
+      if (updatedLexerActions.empty()) {
+        updatedLexerActions = _lexerActions; // Make a copy.
+      }
+      updatedLexerActions[i] = std::make_shared<LexerIndexedCustomAction>(offset, _lexerActions[i]);
+    }
+  }
+  if (updatedLexerActions.empty()) {
+    return shared_from_this();
+  }
+  return std::make_shared<LexerActionExecutor>(std::move(updatedLexerActions));
+}
+
+const std::vector<Ref<const LexerAction>>& LexerActionExecutor::getLexerActions() const {
+  return _lexerActions;
+}
+
+void LexerActionExecutor::execute(Lexer *lexer, CharStream *input, size_t startIndex) const {
+  bool requiresSeek = false;
+  size_t stopIndex = input->index();
+
+  auto onExit = finally([requiresSeek, input, stopIndex]() {
+    if (requiresSeek) {
+      input->seek(stopIndex);
+    }
+  });
+  for (const auto &lexerAction : _lexerActions) {
+    if (LexerIndexedCustomAction::is(*lexerAction)) {
+      int offset = downCast<const LexerIndexedCustomAction&>(*lexerAction).getOffset();
+      input->seek(startIndex + offset);
+      requiresSeek = (startIndex + offset) != stopIndex;
+    } else if (lexerAction->isPositionDependent()) {
+      input->seek(stopIndex);
+      requiresSeek = false;
+    }
+    lexerAction->execute(lexer);
+  }
+}
+
+size_t LexerActionExecutor::hashCode() const {
+  auto hash = _hashCode.load(std::memory_order_relaxed);
+  if (hash == 0) {
+    hash = MurmurHash::initialize();
+    for (const auto &lexerAction : _lexerActions) {
+      hash = MurmurHash::update(hash, lexerAction);
+    }
+    hash = MurmurHash::finish(hash, _lexerActions.size());
+    if (hash == 0) {
+      hash = std::numeric_limits<size_t>::max();
+    }
+    _hashCode.store(hash, std::memory_order_relaxed);
+  }
+  return hash;
+}
+
+bool LexerActionExecutor::equals(const LexerActionExecutor &other) const {
+  if (this == std::addressof(other)) {
+    return true;
+  }
+  return cachedHashCodeEqual(_hashCode.load(std::memory_order_relaxed), other._hashCode.load(std::memory_order_relaxed)) &&
+         _lexerActions.size() == other._lexerActions.size() &&
+         std::equal(_lexerActions.begin(), _lexerActions.end(), other._lexerActions.begin(), lexerActionEqual);
+}