First step to cleanup the power-of-2 mess.

src/base/macros.h

 // 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.
 
 #ifndef V8_BASE_MACROS_H_
 #define V8_BASE_MACROS_H_
 
 #include "include/v8stdint.h"
 #include "src/base/build_config.h"
 #include "src/base/compiler-specific.h"
@@ skipping 170 matching lines @@
 
 // The USE(x) template is used to silence C++ compiler warnings
 // issued for (yet) unused variables (typically parameters).
 template <typename T>
 inline void USE(T) { }
 
 
 #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
@@ skipping 52 matching lines @@
 // 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));
+  DCHECK(IS_POWER_OF_TWO(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_