[turbofan] add RegisterConfiguration to decouple arch specific register layouts from compiler

src/compiler/register-configuration.cc

+// Copyright 2014 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/compiler/register-configuration.h"
+#include "src/macro-assembler.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+namespace {
+
+STATIC_ASSERT(RegisterConfiguration::kMaxGeneralRegisters >=
+              Register::kNumRegisters);
+STATIC_ASSERT(RegisterConfiguration::kMaxDoubleRegisters >=
+              DoubleRegister::kMaxNumRegisters);
+
+class ArchDefaultRegisterConfiguration : public RegisterConfiguration {
+ public:
+  ArchDefaultRegisterConfiguration()
+      : RegisterConfiguration(Register::kMaxNumAllocatableRegisters,
+                              DoubleRegister::kMaxNumAllocatableRegisters,
+                              DoubleRegister::NumAllocatableAliasedRegisters(),
+                              general_register_name_table_,
+                              double_register_name_table_) {
+    DCHECK_EQ(Register::kMaxNumAllocatableRegisters,
+              Register::NumAllocatableRegisters());
+    for (int i = 0; i < Register::kMaxNumAllocatableRegisters; ++i) {
+      general_register_name_table_[i] = Register::AllocationIndexToString(i);
+    }
+    for (int i = 0; i < DoubleRegister::kMaxNumAllocatableRegisters; ++i) {
+      double_register_name_table_[i] =
+          DoubleRegister::AllocationIndexToString(i);
+    }
+  }
+
+  const char*
+      general_register_name_table_[Register::kMaxNumAllocatableRegisters];
+  const char*
+      double_register_name_table_[DoubleRegister::kMaxNumAllocatableRegisters];
+};
+
+
+static base::LazyInstance<ArchDefaultRegisterConfiguration>::type
+    kDefaultRegisterConfiguration = LAZY_INSTANCE_INITIALIZER;
+
+}  // namepace
+
+
+const RegisterConfiguration* RegisterConfiguration::ArchDefault() {
+  return &kDefaultRegisterConfiguration.Get();
+}
+
+RegisterConfiguration::RegisterConfiguration(
+    int num_general_registers, int num_double_registers,
+    int num_aliased_double_registers, const char* const* general_register_names,
+    const char* const* double_register_names)
+    : num_general_registers_(num_general_registers),
+      num_double_registers_(num_double_registers),
+      num_aliased_double_registers_(num_aliased_double_registers),
+      general_register_names_(general_register_names),
+      double_register_names_(double_register_names) {}
+
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8