1 files changed, 6 insertions, 0 deletions
diff --git a/absl/base/optimization.h b/absl/base/optimization.h
index 6974f1f60777..0dcbef32a3c5 100644
--- a/absl/base/optimization.h
+++ b/absl/base/optimization.h
@@ -163,6 +163,12 @@
 // Compilers can use the information that a certain branch is not likely to be
 // taken (for instance, a CHECK failure) to optimize for the common case in
 // the absence of better information (ie. compiling gcc with `-fprofile-arcs`).
+//
+// Recommendation: Modern CPUs dynamically predict branch execution paths,
+// typically with accuracy greater than 97%. As a result, annotating every
+// branch in a codebase is likely counterproductive; however, annotating
+// specific branches that are both hot and consistently mispredicted is likely
+// to yield performance improvements.
 #if ABSL_HAVE_BUILTIN(__builtin_expect) || \
     (defined(__GNUC__) && !defined(__clang__))
 #define ABSL_PREDICT_FALSE(x) (__builtin_expect(x, 0))