Merge experimental/a64 to bleeding_edge.

src/a64/cpu-a64.h

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef V8_A64_CPU_A64_H_
+#define V8_A64_CPU_A64_H_
+
+#include <stdio.h>
+#include "serialize.h"
+#include "cpu.h"
+
+namespace v8 {
+namespace internal {
+
+
+// CpuFeatures keeps track of which features are supported by the target CPU.
+// Supported features must be enabled by a CpuFeatureScope before use.
+class CpuFeatures : public AllStatic {
+ public:
+  // Detect features of the target CPU. Set safe defaults if the serializer
+  // is enabled (snapshots must be portable).
+  static void Probe();
+
+  // Check whether a feature is supported by the target CPU.
+  static bool IsSupported(CpuFeature f) {
+    ASSERT(initialized_);
+    // There are no optional features for A64.
+    return false;
+  };
+
+  static bool IsFoundByRuntimeProbingOnly(CpuFeature f) {
+    ASSERT(initialized_);
+    // There are no optional features for A64.
+    return false;
+  }
+
+  static bool IsSafeForSnapshot(CpuFeature f) {
+    return (IsSupported(f) &&
+            (!Serializer::enabled() || !IsFoundByRuntimeProbingOnly(f)));
+  }
+
+  // I and D cache line size in bytes.
+  static unsigned dcache_line_size();
+  static unsigned icache_line_size();
+
+  static unsigned supported_;
+
+  static bool VerifyCrossCompiling() {
+    // There are no optional features for A64.
+    ASSERT(cross_compile_ == 0);
+    return true;
+  }
+
+  static bool VerifyCrossCompiling(CpuFeature f) {
+    // There are no optional features for A64.
+    USE(f);
+    ASSERT(cross_compile_ == 0);
+    return true;
+  }
+
+ private:
+  // Return the content of the cache type register.
+  static uint32_t GetCacheType();
+
+  // I and D cache line size in bytes.
+  static unsigned icache_line_size_;
+  static unsigned dcache_line_size_;
+
+#ifdef DEBUG
+  static bool initialized_;
+#endif
+
+  // This isn't used (and is always 0), but it is required by V8.
+  static unsigned found_by_runtime_probing_only_;
+
+  static unsigned cross_compile_;
+
+  friend class PlatformFeatureScope;
+  DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
+};
+
+} }  // namespace v8::internal
+
+#endif  // V8_A64_CPU_A64_H_