Move SaturatedArithmetic from Blink to base

base/numerics/saturated_arithmetic_arm.h

-// Copyright 2014 The Chromium Authors. All rights reserved.
+// Copyright 2016 The Chromium 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 SaturatedArithmeticARM_h
-#define SaturatedArithmeticARM_h
+#ifndef BASE_NUMERICS_SATURATED_ARITHMETIC_ARM_H_
+#define BASE_NUMERICS_SATURATED_ARITHMETIC_ARM_H_
 
-#include "wtf/CPU.h"
 #include <limits>
-#include <stdint.h>
 
-ALWAYS_INLINE int32_t saturatedAddition(int32_t a, int32_t b) {
+namespace base {
+
+inline int32_t SaturatedAddition(int32_t a, int32_t b) {
   int32_t result;
 
   asm("qadd %[output],%[first],%[second]"
       : [output] "=r"(result)
       : [first] "r"(a), [second] "r"(b));
 
   return result;
 }
 
-ALWAYS_INLINE int32_t saturatedSubtraction(int32_t a, int32_t b) {
+inline int32_t SaturatedSubtraction(int32_t a, int32_t b) {
   int32_t result;
 
   asm("qsub %[output],%[first],%[second]"
       : [output] "=r"(result)
       : [first] "r"(a), [second] "r"(b));
 
   return result;
 }
 
-ALWAYS_INLINE int32_t saturatedNegative(int32_t a) {
-  return saturatedSubtraction(0, a);
+inline int32_t SaturatedNegative(int32_t a) {
+  return SaturatedSubtraction(0, a);
 }
 
-inline int getMaxSaturatedSetResultForTesting(int FractionalShift) {
+inline int GetMaxSaturatedSetResultForTesting(int fractional_shift) {
   // For ARM Asm version the set function maxes out to the biggest
   // possible integer part with the fractional part zero'd out.
   // e.g. 0x7fffffc0.
-  return std::numeric_limits<int>::max() & ~((1 << FractionalShift) - 1);
+  return std::numeric_limits<int>::max() & ~((1 << fractional_shift) - 1);
 }
 
-inline int getMinSaturatedSetResultForTesting(int FractionalShift) {
+inline int GetMinSaturatedSetResultForTesting(int fractional_shift) {
   return std::numeric_limits<int>::min();
 }
 
 template <int FractionalShift>
-ALWAYS_INLINE int saturatedSet(int value) {
+inline int SaturatedSet(int value) {
   // Figure out how many bits are left for storing the integer part of
   // the fixed point number, and saturate our input to that
   enum { Saturate = 32 - FractionalShift };
 
   int result;
 
   // The following ARM code will Saturate the passed value to the number of
   // bits used for the whole part of the fixed point representation, then
   // shift it up into place. This will result in the low <FractionShift> bits
   // all being 0's. When the value saturates this gives a different result
   // to from the C++ case; in the C++ code a saturated value has all the low
   // bits set to 1 (for a +ve number at least). This cannot be done rapidly
   // in ARM ... we live with the difference, for the sake of speed.
 
   asm("ssat %[output],%[saturate],%[value]\n\t"
       "lsl  %[output],%[shift]"
       : [output] "=r"(result)
       : [value] "r"(value), [saturate] "n"(Saturate),
         [shift] "n"(FractionalShift));
 
   return result;
 }
 
 template <int FractionalShift>
-ALWAYS_INLINE int saturatedSet(unsigned value) {
+inline int SaturatedSet(unsigned value) {
   // Here we are being passed an unsigned value to saturate,
   // even though the result is returned as a signed integer. The ARM
   // instruction for unsigned saturation therefore needs to be given one
   // less bit (i.e. the sign bit) for the saturation to work correctly; hence
   // the '31' below.
   enum { Saturate = 31 - FractionalShift };
 
   // The following ARM code will Saturate the passed value to the number of
   // bits used for the whole part of the fixed point representation, then
   // shift it up into place. This will result in the low <FractionShift> bits
   // all being 0's. When the value saturates this gives a different result
   // to from the C++ case; in the C++ code a saturated value has all the low
   // bits set to 1. This cannot be done rapidly in ARM, so we live with the
   // difference, for the sake of speed.
 
   int result;
 
   asm("usat %[output],%[saturate],%[value]\n\t"
       "lsl  %[output],%[shift]"
       : [output] "=r"(result)
       : [value] "r"(value), [saturate] "n"(Saturate),
         [shift] "n"(FractionalShift));
 
   return result;
 }
 
-#endif  // SaturatedArithmeticARM_h
+}  // namespace base
+
+#endif  // BASE_NUMERICS_SATURATED_ARITHMETIC_ARM_H_