1 files changed, 51 insertions, 0 deletions
diff --git a/deps/v8/src/wasm/local-decl-encoder.cc b/deps/v8/src/wasm/local-decl-encoder.cc
new file mode 100644
index 0000000000..cf50cd0df4
--- /dev/null
+++ b/deps/v8/src/wasm/local-decl-encoder.cc
@@ -0,0 +1,51 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/wasm/local-decl-encoder.h"
+
+#include "src/wasm/leb-helper.h"
+
+using namespace v8::internal;
+using namespace v8::internal::wasm;
+
+void LocalDeclEncoder::Prepend(Zone* zone, const byte** start,
+                               const byte** end) const {
+  size_t size = (*end - *start);
+  byte* buffer = reinterpret_cast<byte*>(zone->New(Size() + size));
+  size_t pos = Emit(buffer);
+  memcpy(buffer + pos, *start, size);
+  pos += size;
+  *start = buffer;
+  *end = buffer + pos;
+}
+
+size_t LocalDeclEncoder::Emit(byte* buffer) const {
+  byte* pos = buffer;
+  LEBHelper::write_u32v(&pos, static_cast<uint32_t>(local_decls.size()));
+  for (auto& local_decl : local_decls) {
+    LEBHelper::write_u32v(&pos, local_decl.first);
+    *pos = WasmOpcodes::ValueTypeCodeFor(local_decl.second);
+    ++pos;
+  }
+  DCHECK_EQ(Size(), pos - buffer);
+  return static_cast<size_t>(pos - buffer);
+}
+
+uint32_t LocalDeclEncoder::AddLocals(uint32_t count, ValueType type) {
+  uint32_t result =
+      static_cast<uint32_t>(total + (sig ? sig->parameter_count() : 0));
+  total += count;
+  if (local_decls.size() > 0 && local_decls.back().second == type) {
+    count += local_decls.back().first;
+    local_decls.pop_back();
+  }
+  local_decls.push_back(std::pair<uint32_t, ValueType>(count, type));
+  return result;
+}
+
+size_t LocalDeclEncoder::Size() const {
+  size_t size = LEBHelper::sizeof_u32v(local_decls.size());
+  for (auto p : local_decls) size += 1 + LEBHelper::sizeof_u32v(p.first);
+  return size;
+}