runtime/vm/globals.h - sdk - Git at Google

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 #ifndef RUNTIME_VM_GLOBALS_H_
 #define RUNTIME_VM_GLOBALS_H_

 // This file contains global definitions for the VM library only. Anything that
 // is more globally useful should be added to 'vm/globals.h'.

 #include "platform/globals.h"

 #if defined(_WIN32)
 // Undef conflicting defines.
 #undef PARITY_EVEN
 #undef PARITY_ODD
 #undef near
 #endif  // defined(_WIN32)

 namespace dart {
 // Smi value range is from -(2^N) to (2^N)-1.
 // N=30 (32-bit build) or N=62 (64-bit build).
 #if !defined(DART_COMPRESSED_POINTERS)
 const intptr_t kSmiBits = kBitsPerWord - 2;
 #else
 const intptr_t kSmiBits = 30;
 #endif
 const intptr_t kSmiMax = (static_cast<intptr_t>(1) << kSmiBits) - 1;
 const intptr_t kSmiMin = -(static_cast<intptr_t>(1) << kSmiBits);

 // Hard coded from above but for 32-bit architectures.
 const intptr_t kSmiBits32 = kBitsPerInt32 - 2;
 const intptr_t kSmiMax32 = (static_cast<intptr_t>(1) << kSmiBits32) - 1;
 const intptr_t kSmiMin32 = -(static_cast<intptr_t>(1) << kSmiBits32);

 #if !defined(DART_COMPRESSED_POINTERS)
 const intptr_t kCompressedWordSize = kWordSize;
 #else
 const intptr_t kCompressedWordSize = sizeof(uint32_t);
 #endif

 // Number of bytes per BigInt digit.
 const intptr_t kBytesPerBigIntDigit = 4;

 // The default old gen heap size in MB, where 0 == unlimited.
 // 32-bit: OS limit is 2 or 3 GB
 // 64-bit: Linux's limit is
 //   sysctl vm.max_map_count (default 2^16) * 512 KB OldPages = 32 GB
 // Set the VM limit below the OS limit to increase the likelihood of failing
 // gracefully with a Dart OutOfMemory exception instead of SIGABORT.
 const intptr_t kDefaultMaxOldGenHeapSize = (kWordSize <= 4) ? 1536 : 30720;

 #define kPosInfinity bit_cast<double>(DART_UINT64_C(0x7ff0000000000000))
 #define kNegInfinity bit_cast<double>(DART_UINT64_C(0xfff0000000000000))

 // The expression ARRAY_SIZE(array) is a compile-time constant of type
 // size_t which represents the number of elements of the given
 // array. You should only use ARRAY_SIZE on statically allocated
 // arrays.
 #define ARRAY_SIZE(array)                                                      \
   ((sizeof(array) / sizeof(*(array))) /                                        \
    static_cast<intptr_t>(!(sizeof(array) % sizeof(*(array)))))  // NOLINT

 #if defined(PRODUCT) && defined(DEBUG)
 #error Both PRODUCT and DEBUG defined.
 #endif  // defined(PRODUCT) && defined(DEBUG)

 #if defined(PRODUCT)
 #define NOT_IN_PRODUCT(code)
 #else  // defined(PRODUCT)
 #define NOT_IN_PRODUCT(code) code
 #endif  // defined(PRODUCT)

 #if defined(DART_PRECOMPILED_RUNTIME) && defined(DART_PRECOMPILER)
 #error DART_PRECOMPILED_RUNTIME and DART_PRECOMPILER are mutually exclusive
 #endif  // defined(DART_PRECOMPILED_RUNTIME) && defined(DART_PRECOMPILER)

 #if defined(DART_PRECOMPILED_RUNTIME) && defined(DART_NOSNAPSHOT)
 #error DART_PRECOMPILED_RUNTIME and DART_NOSNAPSHOT are mutually exclusive
 #endif  // defined(DART_PRECOMPILED_RUNTIME) && defined(DART_NOSNAPSHOT)

 #if defined(DART_PRECOMPILED_RUNTIME)
 #define NOT_IN_PRECOMPILED(code)
 #else
 #define NOT_IN_PRECOMPILED(code) code
 #endif  // defined(DART_PRECOMPILED_RUNTIME)

 #if defined(DART_PRECOMPILED_RUNTIME)
 #define ONLY_IN_PRECOMPILED(code) code
 #else
 #define ONLY_IN_PRECOMPILED(code)
 #endif  // defined(DART_PRECOMPILED_RUNTIME)

 #if defined(TARGET_ARCH_ARM) || defined(TARGET_ARCH_ARM64) ||                  \
     defined(TARGET_ARCH_X64)
 #define ONLY_IN_ARM_ARM64_X64(code) code
 #else
 #define ONLY_IN_ARM_ARM64_X64(code)
 #endif

 #if defined(DART_PRECOMPILED_RUNTIME)
 #define NOT_IN_PRECOMPILED_RUNTIME(code)
 #else
 #define NOT_IN_PRECOMPILED_RUNTIME(code) code
 #endif  // defined(DART_PRECOMPILED_RUNTIME)

 #if !defined(PRODUCT) || defined(HOST_OS_FUCHSIA) || defined(TARGET_OS_FUCHSIA)
 #define SUPPORT_TIMELINE 1
 #endif

 #if defined(ARCH_IS_64_BIT) && !defined(IS_SIMARM_X64)
 #define HASH_IN_OBJECT_HEADER 1
 #endif

 // The expression OFFSET_OF(type, field) computes the byte-offset of
 // the specified field relative to the containing type.
 //
 // The expression OFFSET_OF_RETURNED_VALUE(type, accessor) computes the
 // byte-offset of the return value of the accessor to the containing type.
 //
 // None of these use 0 or NULL, which causes a problem with the compiler
 // warnings we have enabled (which is also why 'offsetof' doesn't seem to work).
 // The workaround is to use the non-zero value kOffsetOfPtr.
 const intptr_t kOffsetOfPtr = 32;

 #define OFFSET_OF(type, field)                                                 \
   (reinterpret_cast<intptr_t>(                                                 \
        &(reinterpret_cast<type*>(kOffsetOfPtr)->field)) -                      \
    kOffsetOfPtr)  // NOLINT

 #define OFFSET_OF_RETURNED_VALUE(type, accessor)                               \
   (reinterpret_cast<intptr_t>(                                                 \
        (reinterpret_cast<type*>(kOffsetOfPtr)->accessor())) -                  \
    kOffsetOfPtr)  // NOLINT

 #define SIZE_OF_RETURNED_VALUE(type, method)                                   \
   sizeof(reinterpret_cast<type*>(kOffsetOfPtr)->method())

 #define SIZE_OF_DEREFERENCED_RETURNED_VALUE(type, method)                      \
   sizeof(*(reinterpret_cast<type*>(kOffsetOfPtr))->method())

 #define OPEN_ARRAY_START(type, align)                                          \
   do {                                                                         \
     const uword result = reinterpret_cast<uword>(this) + sizeof(*this);        \
     ASSERT(Utils::IsAligned(result, sizeof(align)));                           \
     return reinterpret_cast<type*>(result);                                    \
   } while (0)

 // A type large enough to contain the value of the C++ vtable. This is needed
 // to support the handle operations.
 typedef uword cpp_vtable;

 // When using GCC we can use GCC attributes to ensure that certain
 // constants are 8 or 16 byte aligned.
 #if defined(HOST_OS_WINDOWS)
 #define ALIGN8 __declspec(align(8))
 #define ALIGN16 __declspec(align(16))
 #else
 #define ALIGN8 __attribute__((aligned(8)))
 #define ALIGN16 __attribute__((aligned(16)))
 #endif

 // Zap value used to indicate uninitialized handle area (debug purposes).
 #if defined(ARCH_IS_32_BIT)
 static const uword kZapUninitializedWord = 0xabababab;
 #else
 static const uword kZapUninitializedWord = 0xabababababababab;
 #endif

 // Macros to get the contents of the fp register.
 #if defined(HOST_OS_WINDOWS)

 // clang-format off
 #if defined(HOST_ARCH_IA32)
 #define COPY_FP_REGISTER(fp)                                                   \
   __asm { mov fp, ebp}                                                         \
   ;  // NOLINT
 // clang-format on
 #elif defined(HOST_ARCH_X64)
 // We don't have the asm equivalent to get at the frame pointer on
 // windows x64, return the stack pointer instead.
 #define COPY_FP_REGISTER(fp) fp = OSThread::GetCurrentStackPointer();
 #else
 #error Unknown host architecture.
 #endif

 #else  // !defined(HOST_OS_WINDOWS))

 // Assume GCC-compatible builtins.
 #define COPY_FP_REGISTER(fp)                                                   \
   fp = reinterpret_cast<uintptr_t>(__builtin_frame_address(0));

 #endif  // !defined(HOST_OS_WINDOWS))

 #if defined(TARGET_ARCH_ARM) || defined(TARGET_ARCH_ARM64) ||                  \
     defined(TARGET_ARCH_X64)
 #define TARGET_USES_OBJECT_POOL 1
 #endif

 #if defined(DART_PRECOMPILER) &&                                               \
     (defined(TARGET_ARCH_X64) || defined(TARGET_ARCH_ARM) ||                   \
      defined(TARGET_ARCH_ARM64))
 #define DART_SUPPORT_PRECOMPILATION 1
 #endif

 }  // namespace dart

 #endif  // RUNTIME_VM_GLOBALS_H_
	// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	#ifndef RUNTIME_VM_GLOBALS_H_
	#define RUNTIME_VM_GLOBALS_H_

	// This file contains global definitions for the VM library only. Anything that
	// is more globally useful should be added to 'vm/globals.h'.

	#include "platform/globals.h"

	#if defined(_WIN32)
	// Undef conflicting defines.
	#undef PARITY_EVEN
	#undef PARITY_ODD
	#undef near
	#endif // defined(_WIN32)

	namespace dart {
	// Smi value range is from -(2^N) to (2^N)-1.
	// N=30 (32-bit build) or N=62 (64-bit build).
	#if !defined(DART_COMPRESSED_POINTERS)
	const intptr_t kSmiBits = kBitsPerWord - 2;
	#else
	const intptr_t kSmiBits = 30;
	#endif
	const intptr_t kSmiMax = (static_cast<intptr_t>(1) << kSmiBits) - 1;
	const intptr_t kSmiMin = -(static_cast<intptr_t>(1) << kSmiBits);

	// Hard coded from above but for 32-bit architectures.
	const intptr_t kSmiBits32 = kBitsPerInt32 - 2;
	const intptr_t kSmiMax32 = (static_cast<intptr_t>(1) << kSmiBits32) - 1;
	const intptr_t kSmiMin32 = -(static_cast<intptr_t>(1) << kSmiBits32);

	#if !defined(DART_COMPRESSED_POINTERS)
	const intptr_t kCompressedWordSize = kWordSize;
	#else
	const intptr_t kCompressedWordSize = sizeof(uint32_t);
	#endif

	// Number of bytes per BigInt digit.
	const intptr_t kBytesPerBigIntDigit = 4;

	// The default old gen heap size in MB, where 0 == unlimited.
	// 32-bit: OS limit is 2 or 3 GB
	// 64-bit: Linux's limit is
	// sysctl vm.max_map_count (default 2^16) * 512 KB OldPages = 32 GB
	// Set the VM limit below the OS limit to increase the likelihood of failing
	// gracefully with a Dart OutOfMemory exception instead of SIGABORT.
	const intptr_t kDefaultMaxOldGenHeapSize = (kWordSize <= 4) ? 1536 : 30720;

	#define kPosInfinity bit_cast<double>(DART_UINT64_C(0x7ff0000000000000))
	#define kNegInfinity bit_cast<double>(DART_UINT64_C(0xfff0000000000000))

	// The expression ARRAY_SIZE(array) is a compile-time constant of type
	// size_t which represents the number of elements of the given
	// array. You should only use ARRAY_SIZE on statically allocated
	// arrays.
	#define ARRAY_SIZE(array) \
	((sizeof(array) / sizeof(*(array))) / \
	static_cast<intptr_t>(!(sizeof(array) % sizeof(*(array))))) // NOLINT

	#if defined(PRODUCT) && defined(DEBUG)
	#error Both PRODUCT and DEBUG defined.
	#endif // defined(PRODUCT) && defined(DEBUG)

	#if defined(PRODUCT)
	#define NOT_IN_PRODUCT(code)
	#else // defined(PRODUCT)
	#define NOT_IN_PRODUCT(code) code
	#endif // defined(PRODUCT)

	#if defined(DART_PRECOMPILED_RUNTIME) && defined(DART_PRECOMPILER)
	#error DART_PRECOMPILED_RUNTIME and DART_PRECOMPILER are mutually exclusive
	#endif // defined(DART_PRECOMPILED_RUNTIME) && defined(DART_PRECOMPILER)

	#if defined(DART_PRECOMPILED_RUNTIME) && defined(DART_NOSNAPSHOT)
	#error DART_PRECOMPILED_RUNTIME and DART_NOSNAPSHOT are mutually exclusive
	#endif // defined(DART_PRECOMPILED_RUNTIME) && defined(DART_NOSNAPSHOT)

	#if defined(DART_PRECOMPILED_RUNTIME)
	#define NOT_IN_PRECOMPILED(code)
	#else
	#define NOT_IN_PRECOMPILED(code) code
	#endif // defined(DART_PRECOMPILED_RUNTIME)

	#if defined(DART_PRECOMPILED_RUNTIME)
	#define ONLY_IN_PRECOMPILED(code) code
	#else
	#define ONLY_IN_PRECOMPILED(code)
	#endif // defined(DART_PRECOMPILED_RUNTIME)

	#if defined(TARGET_ARCH_ARM) \|\| defined(TARGET_ARCH_ARM64) \|\| \
	defined(TARGET_ARCH_X64)
	#define ONLY_IN_ARM_ARM64_X64(code) code
	#else
	#define ONLY_IN_ARM_ARM64_X64(code)
	#endif

	#if defined(DART_PRECOMPILED_RUNTIME)
	#define NOT_IN_PRECOMPILED_RUNTIME(code)
	#else
	#define NOT_IN_PRECOMPILED_RUNTIME(code) code
	#endif // defined(DART_PRECOMPILED_RUNTIME)

	#if !defined(PRODUCT) \|\| defined(HOST_OS_FUCHSIA) \|\| defined(TARGET_OS_FUCHSIA)
	#define SUPPORT_TIMELINE 1
	#endif

	#if defined(ARCH_IS_64_BIT) && !defined(IS_SIMARM_X64)
	#define HASH_IN_OBJECT_HEADER 1
	#endif

	// The expression OFFSET_OF(type, field) computes the byte-offset of
	// the specified field relative to the containing type.
	//
	// The expression OFFSET_OF_RETURNED_VALUE(type, accessor) computes the
	// byte-offset of the return value of the accessor to the containing type.
	//
	// None of these use 0 or NULL, which causes a problem with the compiler
	// warnings we have enabled (which is also why 'offsetof' doesn't seem to work).
	// The workaround is to use the non-zero value kOffsetOfPtr.
	const intptr_t kOffsetOfPtr = 32;

	#define OFFSET_OF(type, field) \
	(reinterpret_cast<intptr_t>( \
	&(reinterpret_cast<type*>(kOffsetOfPtr)->field)) - \
	kOffsetOfPtr) // NOLINT

	#define OFFSET_OF_RETURNED_VALUE(type, accessor) \
	(reinterpret_cast<intptr_t>( \
	(reinterpret_cast<type*>(kOffsetOfPtr)->accessor())) - \
	kOffsetOfPtr) // NOLINT

	#define SIZE_OF_RETURNED_VALUE(type, method) \
	sizeof(reinterpret_cast<type*>(kOffsetOfPtr)->method())

	#define SIZE_OF_DEREFERENCED_RETURNED_VALUE(type, method) \
	sizeof((reinterpret_cast<type>(kOffsetOfPtr))->method())

	#define OPEN_ARRAY_START(type, align) \
	do { \
	const uword result = reinterpret_cast<uword>(this) + sizeof(*this); \
	ASSERT(Utils::IsAligned(result, sizeof(align))); \
	return reinterpret_cast<type*>(result); \
	} while (0)

	// A type large enough to contain the value of the C++ vtable. This is needed
	// to support the handle operations.
	typedef uword cpp_vtable;

	// When using GCC we can use GCC attributes to ensure that certain
	// constants are 8 or 16 byte aligned.
	#if defined(HOST_OS_WINDOWS)
	#define ALIGN8 __declspec(align(8))
	#define ALIGN16 __declspec(align(16))
	#else
	#define ALIGN8 __attribute__((aligned(8)))
	#define ALIGN16 __attribute__((aligned(16)))
	#endif

	// Zap value used to indicate uninitialized handle area (debug purposes).
	#if defined(ARCH_IS_32_BIT)
	static const uword kZapUninitializedWord = 0xabababab;
	#else
	static const uword kZapUninitializedWord = 0xabababababababab;
	#endif

	// Macros to get the contents of the fp register.
	#if defined(HOST_OS_WINDOWS)

	// clang-format off
	#if defined(HOST_ARCH_IA32)
	#define COPY_FP_REGISTER(fp) \
	__asm { mov fp, ebp} \
	; // NOLINT
	// clang-format on
	#elif defined(HOST_ARCH_X64)
	// We don't have the asm equivalent to get at the frame pointer on
	// windows x64, return the stack pointer instead.
	#define COPY_FP_REGISTER(fp) fp = OSThread::GetCurrentStackPointer();
	#else
	#error Unknown host architecture.
	#endif

	#else // !defined(HOST_OS_WINDOWS))

	// Assume GCC-compatible builtins.
	#define COPY_FP_REGISTER(fp) \
	fp = reinterpret_cast<uintptr_t>(__builtin_frame_address(0));

	#endif // !defined(HOST_OS_WINDOWS))

	#if defined(TARGET_ARCH_ARM) \|\| defined(TARGET_ARCH_ARM64) \|\| \
	defined(TARGET_ARCH_X64)
	#define TARGET_USES_OBJECT_POOL 1
	#endif

	#if defined(DART_PRECOMPILER) && \
	(defined(TARGET_ARCH_X64) \|\| defined(TARGET_ARCH_ARM) \|\| \
	defined(TARGET_ARCH_ARM64))
	#define DART_SUPPORT_PRECOMPILATION 1
	#endif

	} // namespace dart

	#endif // RUNTIME_VM_GLOBALS_H_