[interpreter] Implement exception handler table building.

src/interpreter/handler-table-builder.cc

+// Copyright 2016 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/interpreter/handler-table-builder.h"
+
+#include "src/factory.h"
+#include "src/isolate.h"
+#include "src/objects-inl.h"
+
+namespace v8 {
+namespace internal {
+namespace interpreter {
+
+HandlerTableBuilder::HandlerTableBuilder(Isolate* isolate, Zone* zone)
+    : isolate_(isolate), entries_(zone) {}
+
+Handle<HandlerTable> HandlerTableBuilder::ToHandlerTable() {
+  int handler_table_size = static_cast<int>(entries_.size());
+  Handle<HandlerTable> table =
+      Handle<HandlerTable>::cast(isolate_->factory()->NewFixedArray(
+          HandlerTable::LengthForRange(handler_table_size), TENURED));
+  for (int i = 0; i < handler_table_size; ++i) {
+    Entry& entry = entries_[i];
+    HandlerTable::CatchPrediction pred =
+        entry.will_catch ? HandlerTable::CAUGHT : HandlerTable::UNCAUGHT;
+    table->SetRangeStart(i, static_cast<int>(entry.offset_start));
+    table->SetRangeEnd(i, static_cast<int>(entry.offset_end));
+    table->SetRangeHandler(i, static_cast<int>(entry.offset_target), pred);
+    table->SetRangeDepth(i, entry.context.index());
+  }
+  return table;
+}
+
+
+int HandlerTableBuilder::NewHandlerEntry() {
+  int handler_id = static_cast<int>(entries_.size());
+  Entry entry = {0, 0, 0, Register(), false};
+  entries_.push_back(entry);
+  return handler_id;
+}
+
+
+void HandlerTableBuilder::SetTryRegionStart(int handler_id, size_t offset) {
+  DCHECK(Smi::IsValid(offset));  // Encoding of handler table requires this.
+  entries_[handler_id].offset_start = offset;
+}
+
+
+void HandlerTableBuilder::SetTryRegionEnd(int handler_id, size_t offset) {
+  DCHECK(Smi::IsValid(offset));  // Encoding of handler table requires this.
+  entries_[handler_id].offset_end = offset;
+}
+
+
+void HandlerTableBuilder::SetHandlerTarget(int handler_id, size_t offset) {
+  DCHECK(Smi::IsValid(offset));  // Encoding of handler table requires this.
+  entries_[handler_id].offset_target = offset;
+}
+
+
+void HandlerTableBuilder::SetPrediction(int handler_id, bool will_catch) {
+  entries_[handler_id].will_catch = will_catch;
+}
+
+
+void HandlerTableBuilder::SetContextRegister(int handler_id, Register reg) {
+  entries_[handler_id].context = reg;
+}
+
+}  // namespace interpreter
+}  // namespace internal
+}  // namespace v8