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 #ifndef SkBitmapProcState_utils_DEFINED

 #define SkBitmapProcState_utils_DEFINED

 // Helper to ensure that when we shift down, we do it w/o sign-extension

 // so the caller doesn't have to manually mask off the top 16 bits

 //

 static unsigned SK_USHIFT16(unsigned x) {

     return x >> 16;

 }

 /*

  *  The decal_ functions require that

  *  1. dx > 0

  *  2. [fx, fx+dx, fx+2dx, fx+3dx, ... fx+(count-1)dx] are all <= maxX

  *

  *  In addition, we use SkFractionalInt to keep more fractional precision than

  *  just SkFixed, so we will abort the decal_ call if dx is very small, since

  *  the decal_ function just operates on SkFixed. If that were changed, we could

  *  skip the very_small test here.

  */

 static inline bool can_truncate_to_fixed_for_decal(SkFractionalInt frX,

                                                    SkFractionalInt frDx,

                                                    int count, unsigned max) {

     SkFixed dx = SkFractionalIntToFixed(frDx);

     // if decal_ kept SkFractionalInt precision, this would just be dx <= 0

     // I just made up the 1/256. Just don't want to perceive accumulated error

     // if we truncate frDx and lose its low bits.

     if (dx <= SK_Fixed1 / 256) {

         return false;

     }

     // We cast to unsigned so we don't have to check for negative values, which

     // will now appear as very large positive values, and thus fail our test!

     SkFixed fx = SkFractionalIntToFixed(frX);

     return (unsigned)SkFixedFloorToInt(fx) <= max &&

            (unsigned)SkFixedFloorToInt(fx + dx * (count - 1)) < max;

 }

 #endif /* #ifndef SkBitmapProcState_utils_DEFINED */