#define V8_BASE_MACROS_H_
#include "include/v8stdint.h"
+#include "src/base/build_config.h"
+#include "src/base/logging.h"
// The expression OFFSET_OF(type, field) computes the byte-offset
#define IS_POWER_OF_TWO(x) ((x) != 0 && (((x) & ((x) - 1)) == 0))
+
+// Returns true iff x is a power of 2. Cannot be used with the maximally
+// negative value of the type T (the -1 overflows).
+template <typename T>
+inline bool IsPowerOf2(T x) {
+ return IS_POWER_OF_TWO(x);
+}
+
+
+// Define our own macros for writing 64-bit constants. This is less fragile
+// than defining __STDC_CONSTANT_MACROS before including <stdint.h>, and it
+// works on compilers that don't have it (like MSVC).
+#if V8_CC_MSVC
+# define V8_UINT64_C(x) (x ## UI64)
+# define V8_INT64_C(x) (x ## I64)
+# if V8_HOST_ARCH_64_BIT
+# define V8_INTPTR_C(x) (x ## I64)
+# define V8_PTR_PREFIX "ll"
+# else
+# define V8_INTPTR_C(x) (x)
+# define V8_PTR_PREFIX ""
+# endif // V8_HOST_ARCH_64_BIT
+#elif V8_CC_MINGW64
+# define V8_UINT64_C(x) (x ## ULL)
+# define V8_INT64_C(x) (x ## LL)
+# define V8_INTPTR_C(x) (x ## LL)
+# define V8_PTR_PREFIX "I64"
+#elif V8_HOST_ARCH_64_BIT
+# if V8_OS_MACOSX
+# define V8_UINT64_C(x) (x ## ULL)
+# define V8_INT64_C(x) (x ## LL)
+# else
+# define V8_UINT64_C(x) (x ## UL)
+# define V8_INT64_C(x) (x ## L)
+# endif
+# define V8_INTPTR_C(x) (x ## L)
+# define V8_PTR_PREFIX "l"
+#else
+# define V8_UINT64_C(x) (x ## ULL)
+# define V8_INT64_C(x) (x ## LL)
+# define V8_INTPTR_C(x) (x)
+# define V8_PTR_PREFIX ""
+#endif
+
+#define V8PRIxPTR V8_PTR_PREFIX "x"
+#define V8PRIdPTR V8_PTR_PREFIX "d"
+#define V8PRIuPTR V8_PTR_PREFIX "u"
+
+// Fix for Mac OS X defining uintptr_t as "unsigned long":
+#if V8_OS_MACOSX
+#undef V8PRIxPTR
+#define V8PRIxPTR "lx"
+#endif
+
// The following macro works on both 32 and 64-bit platforms.
// Usage: instead of writing 0x1234567890123456
// write V8_2PART_UINT64_C(0x12345678,90123456);
#define V8_2PART_UINT64_C(a, b) (((static_cast<uint64_t>(a) << 32) + 0x##b##u))
+
+// Compute the 0-relative offset of some absolute value x of type T.
+// This allows conversion of Addresses and integral types into
+// 0-relative int offsets.
+template <typename T>
+inline intptr_t OffsetFrom(T x) {
+ return x - static_cast<T>(0);
+}
+
+
+// Compute the absolute value of type T for some 0-relative offset x.
+// This allows conversion of 0-relative int offsets into Addresses and
+// integral types.
+template <typename T>
+inline T AddressFrom(intptr_t x) {
+ return static_cast<T>(static_cast<T>(0) + x);
+}
+
+
+// Return the largest multiple of m which is <= x.
+template <typename T>
+inline T RoundDown(T x, intptr_t m) {
+ DCHECK(IsPowerOf2(m));
+ return AddressFrom<T>(OffsetFrom(x) & -m);
+}
+
+
+// Return the smallest multiple of m which is >= x.
+template <typename T>
+inline T RoundUp(T x, intptr_t m) {
+ return RoundDown<T>(static_cast<T>(x + m - 1), m);
+}
+
+
+// Increment a pointer until it has the specified alignment.
+// This works like RoundUp, but it works correctly on pointer types where
+// sizeof(*pointer) might not be 1.
+template<class T>
+T AlignUp(T pointer, size_t alignment) {
+ DCHECK(sizeof(pointer) == sizeof(uintptr_t));
+ uintptr_t pointer_raw = reinterpret_cast<uintptr_t>(pointer);
+ return reinterpret_cast<T>(RoundUp(pointer_raw, alignment));
+}
+
+
+template <typename T, typename U>
+inline bool IsAligned(T value, U alignment) {
+ return (value & (alignment - 1)) == 0;
+}
+
+
+// Returns the smallest power of two which is >= x. If you pass in a
+// number that is already a power of two, it is returned as is.
+// Implementation is from "Hacker's Delight" by Henry S. Warren, Jr.,
+// figure 3-3, page 48, where the function is called clp2.
+inline uint32_t RoundUpToPowerOf2(uint32_t x) {
+ DCHECK(x <= 0x80000000u);
+ x = x - 1;
+ x = x | (x >> 1);
+ x = x | (x >> 2);
+ x = x | (x >> 4);
+ x = x | (x >> 8);
+ x = x | (x >> 16);
+ return x + 1;
+}
+
+
+inline uint32_t RoundDownToPowerOf2(uint32_t x) {
+ uint32_t rounded_up = RoundUpToPowerOf2(x);
+ if (rounded_up > x) return rounded_up >> 1;
+ return rounded_up;
+}
+
+
+// Returns current value of top of the stack. Works correctly with ASAN.
+DISABLE_ASAN
+inline uintptr_t GetCurrentStackPosition() {
+ // Takes the address of the limit variable in order to find out where
+ // the top of stack is right now.
+ uintptr_t limit = reinterpret_cast<uintptr_t>(&limit);
+ return limit;
+}
+
#endif // V8_BASE_MACROS_H_
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