Small improvements to SkBitSet:

src/utils/SkBitSet.h

Index: src/utils/SkBitSet.h
diff --git a/src/utils/SkBitSet.h b/src/utils/SkBitSet.h
index e113fd70044eb148302977ae70728565f6931426..f6adc5180697d302778698f3db3a53d84f7ed796 100644
--- a/src/utils/SkBitSet.h
+++ b/src/utils/SkBitSet.h
@@ -30,11 +30,21 @@ public:
 
     /** Set the value of the index-th bit.
      */
-    void setBit(int index, bool value);
+    void setBit(int index, bool value) {
+        uint32_t mask = 1 << (index % 32);

[reed1, 2014/10/09 15:53:43]

nit: in skia using % 32 is far more rare than (index & 0x1F)

its also possible, since index is signed, that the two are not equivalent (in
terms of perf).

[mtklein, 2014/10/09 16:12:59]

Done.

Generated code looks fine to me both ways, but might as well use a mask. 
Probably was inlining helping here, effectively letting setBit know index is
actually unsigned.

+        if (value) {
+            *(this->internalGet(index)) |= mask;

[reed1, 2014/10/09 15:53:43]

stylistic:

uint32_t mask = ...
uint32_t* chunk = this->internalGet(index);
if (value) {
    *chunk |= mask;
} else {
    *chunk &= ~mask;
}

I just get the hebejebees seeing the same function called twice, even when I
assume that the compiler will likely only call it once...

[mtklein, 2014/10/09 16:12:59]

Done.

For what it's worth, it had better only call it once.  They're on opposite sides
of an if-statement.  (And now that it's inlined, if we call this with a
compile-time constant value, the whole if-statement compiles away.)

+        } else {
+            *(this->internalGet(index)) &= ~mask;
+        }
+    }
 
     /** Test if bit index is set.
      */
-    bool isBitSet(int index) const;
+    bool isBitSet(int index) const {
+        uint32_t mask = 1 << (index % 32);
+        return 0 != (*this->internalGet(index) & mask);

[reed1, 2014/10/09 15:53:43]

trivial nit: use SkToBool(...) instead?

[mtklein, 2014/10/09 16:12:59]

Done.

+    }
 
     /** Or bits from source.  false is returned if this doesn't have the same
      *  bit count as source.