Move SaturatedArithmetic from Blink to base

third_party/WebKit/Source/wtf/SaturatedArithmetic.h

Index: third_party/WebKit/Source/wtf/SaturatedArithmetic.h
diff --git a/third_party/WebKit/Source/wtf/SaturatedArithmetic.h b/third_party/WebKit/Source/wtf/SaturatedArithmetic.h
index bcea3bfa804420edf970af5447e9087c0b723fbf..c85f291660c7d34bd350c9f5dacdc058610e6662 100644
--- a/third_party/WebKit/Source/wtf/SaturatedArithmetic.h
+++ b/third_party/WebKit/Source/wtf/SaturatedArithmetic.h
@@ -31,90 +31,18 @@
 #ifndef SaturatedArithmetic_h
 #define SaturatedArithmetic_h
 
-#include "wtf/CPU.h"
-#include <limits>
-#include <stdint.h>
+#include "base/numerics/saturated_arithmetic.h"
 
-#if CPU(ARM) && COMPILER(GCC) && __OPTIMIZE__
+namespace WTF {
+using base::SaturatedAddition;
+using base::SaturatedSubtraction;
+using base::SaturatedNegative;
+using base::SaturatedSet;
+}  // namespace WTF
 
-// If we're building ARM on GCC we replace the C++ versions with some
-// native ARM assembly for speed.
-#include "wtf/asm/SaturatedArithmeticARM.h"
+using WTF::SaturatedAddition;
+using WTF::SaturatedSubtraction;
+using WTF::SaturatedNegative;
+using WTF::SaturatedSet;
 
-#else
-
-ALWAYS_INLINE int32_t saturatedAddition(int32_t a, int32_t b) {
-  uint32_t ua = a;
-  uint32_t ub = b;
-  uint32_t result = ua + ub;
-
-  // Can only overflow if the signed bit of the two values match. If the
-  // signed bit of the result and one of the values differ it overflowed.
-  // The branch compiles to a CMOVNS instruction on x86.
-  if (~(ua ^ ub) & (result ^ ua) & (1 << 31))
-    return std::numeric_limits<int>::max() + (ua >> 31);
-
-  return result;
-}
-
-ALWAYS_INLINE int32_t saturatedSubtraction(int32_t a, int32_t b) {
-  uint32_t ua = a;
-  uint32_t ub = b;
-  uint32_t result = ua - ub;
-
-  // Can only overflow if the signed bit of the two input values differ. If
-  // the signed bit of the result and the first value differ it overflowed.
-  // The branch compiles to a CMOVNS instruction on x86.
-  if ((ua ^ ub) & (result ^ ua) & (1 << 31))
-    return std::numeric_limits<int>::max() + (ua >> 31);
-
-  return result;
-}
-
-ALWAYS_INLINE int32_t saturatedNegative(int32_t a) {
-  if (UNLIKELY(a == std::numeric_limits<int>::min()))
-    return std::numeric_limits<int>::max();
-  return -a;
-}
-
-inline int getMaxSaturatedSetResultForTesting(int FractionalShift) {
-  // For C version the set function maxes out to max int, this differs from
-  // the ARM asm version, see SaturatedArithmetiARM.h for the equivalent asm
-  // version.
-  return std::numeric_limits<int>::max();
-}
-
-inline int getMinSaturatedSetResultForTesting(int FractionalShift) {
-  return std::numeric_limits<int>::min();
-}
-
-template <int FractionalShift>
-ALWAYS_INLINE int saturatedSet(int value) {
-  const int intMaxForLayoutUnit =
-      std::numeric_limits<int>::max() >> FractionalShift;
-
-  const int intMinForLayoutUnit =
-      std::numeric_limits<int>::min() >> FractionalShift;
-
-  if (value > intMaxForLayoutUnit)
-    return std::numeric_limits<int>::max();
-
-  if (value < intMinForLayoutUnit)
-    return std::numeric_limits<int>::min();
-
-  return value << FractionalShift;
-}
-
-template <int FractionalShift>
-ALWAYS_INLINE int saturatedSet(unsigned value) {
-  const unsigned intMaxForLayoutUnit =
-      std::numeric_limits<int>::max() >> FractionalShift;
-
-  if (value >= intMaxForLayoutUnit)
-    return std::numeric_limits<int>::max();
-
-  return value << FractionalShift;
-}
-
-#endif  // CPU(ARM) && COMPILER(GCC)
 #endif  // SaturatedArithmetic_h