// Copyright 2018 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. #ifndef V8_TEST_COMMON_ASSEMBLER_TESTER_H_ #define V8_TEST_COMMON_ASSEMBLER_TESTER_H_ #include "src/codegen/assembler.h" #include "src/codegen/code-desc.h" namespace v8 { namespace internal { class TestingAssemblerBuffer : public AssemblerBuffer { public: TestingAssemblerBuffer(size_t requested, void* address) { size_t page_size = v8::internal::AllocatePageSize(); size_t alloc_size = RoundUp(requested, page_size); CHECK_GE(kMaxInt, alloc_size); size_ = static_cast<int>(alloc_size); buffer_ = static_cast<byte*>(AllocatePages(GetPlatformPageAllocator(), address, alloc_size, page_size, v8::PageAllocator::kReadWrite)); CHECK_NOT_NULL(buffer_); } ~TestingAssemblerBuffer() { CHECK(FreePages(GetPlatformPageAllocator(), buffer_, size_)); } byte* start() const override { return buffer_; } int size() const override { return size_; } std::unique_ptr<AssemblerBuffer> Grow(int new_size) override { FATAL("Cannot grow TestingAssemblerBuffer"); } std::unique_ptr<AssemblerBuffer> CreateView() const { return ExternalAssemblerBuffer(buffer_, size_); } void MakeExecutable() { // Flush the instruction cache as part of making the buffer executable. // Note: we do this before setting permissions to ReadExecute because on // some older ARM kernels there is a bug which causes an access error on // cache flush instructions to trigger access error on non-writable memory. // See https://bugs.chromium.org/p/v8/issues/detail?id=8157 FlushInstructionCache(buffer_, size_); bool result = SetPermissions(GetPlatformPageAllocator(), buffer_, size_, v8::PageAllocator::kReadExecute); CHECK(result); } void MakeWritable() { bool result = SetPermissions(GetPlatformPageAllocator(), buffer_, size_, v8::PageAllocator::kReadWrite); CHECK(result); } // TODO(wasm): Only needed for the "test-jump-table-assembler.cc" tests. void MakeWritableAndExecutable() { bool result = SetPermissions(GetPlatformPageAllocator(), buffer_, size_, v8::PageAllocator::kReadWriteExecute); CHECK(result); } private: byte* buffer_; int size_; }; static inline std::unique_ptr<TestingAssemblerBuffer> AllocateAssemblerBuffer( size_t requested = v8::internal::AssemblerBase::kMinimalBufferSize, void* address = nullptr) { return base::make_unique<TestingAssemblerBuffer>(requested, address); } } // namespace internal } // namespace v8 #endif // V8_TEST_COMMON_ASSEMBLER_TESTER_H_