diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index 49a122aab1..521c3642e8 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -434,7 +434,7 @@ DEFINE_BOOL(print_deopt_stress, false, "print number of possible deopt points")
 // Flags for TurboFan.
 DEFINE_BOOL(turbo_sp_frame_access, false,
             "use stack pointer-relative access to frame wherever possible")
-DEFINE_BOOL(turbo_preprocess_ranges, false,
+DEFINE_BOOL(turbo_preprocess_ranges, true,
             "run pre-register allocation heuristics")
 DEFINE_BOOL(turbo_control_flow_aware_allocation, false,
             "consider control flow while allocating registers")