[turbofan] Optimize certain chains of Branch into a Switch.

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index e43f565c3cff7b1ce0b228c2e605f0061b9a461e..b91e56cc12e7ce333ea48158b6d5646e6675d16a 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -424,6 +424,7 @@ DEFINE_BOOL(turbo_osr, false, "enable OSR in TurboFan")
 DEFINE_BOOL(turbo_exceptions, false, "enable exception handling in TurboFan")
 DEFINE_BOOL(turbo_stress_loop_peeling, false,
             "stress loop peeling optimization")
+DEFINE_BOOL(turbo_cf_optimization, true, "optimize control flow in TurboFan")

[Michael Starzinger, 2015/02/17 12:23:35]

nit: Can we just call this --turbo-switch? I assume it is a temporary flag and
for now it only affects switches.

[Benedikt Meurer, 2015/02/17 12:30:39]

Done.

 
 DEFINE_INT(typed_array_max_size_in_heap, 64,
            "threshold for in-heap typed array")