ll_prof: Reduce profiling hooks overhead from >400% to 25%.

src/utils.h

Index: src/utils.h
diff --git a/src/utils.h b/src/utils.h
index b89f2849bfde4d5c2624d94bc14993291ac8608d..6f89766c16dcdc424f5b3e6f27017471f66c9035 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -251,6 +251,12 @@ static inline uint32_t ComputeIntegerHash(uint32_t key) {
 }
 
 
+static inline uint32_t ComputePointerHash(void* ptr) {
+  return ComputeIntegerHash(
+      static_cast<uint32_t>(reinterpret_cast<intptr_t>(ptr)));
+}
+
+
 // ----------------------------------------------------------------------------
 // Miscellaneous