[turbofan] Improve the store-store elimination.

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index c9f788da11d9136910c5590c89fba92602ab31e7..5b7d292891bb6d2e6de578160d38097a95d73425 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -354,6 +354,8 @@ DEFINE_STRING(trace_phase, "HLZ", "trace generated IR for specified phases")
 DEFINE_BOOL(trace_inlining, false, "trace inlining decisions")
 DEFINE_BOOL(trace_load_elimination, false, "trace load elimination")
 DEFINE_BOOL(trace_store_elimination, false, "trace store elimination")
+DEFINE_BOOL(turbo_verify_store_elimination, false,
+            "verify store elimination more rigorously")
 DEFINE_BOOL(trace_alloc, false, "trace register allocator")
 DEFINE_BOOL(trace_all_uses, false, "trace all use positions")
 DEFINE_BOOL(trace_range, false, "trace range analysis")
@@ -423,7 +425,6 @@ DEFINE_BOOL(omit_map_checks_for_leaf_maps, true,
 // Flags for TurboFan.
 DEFINE_BOOL(turbo, false, "enable TurboFan compiler")
 DEFINE_IMPLICATION(turbo, turbo_asm_deoptimization)
-DEFINE_IMPLICATION(turbo, turbo_store_elimination)
 DEFINE_IMPLICATION(turbo, turbo_loop_peeling)
 DEFINE_BOOL(turbo_shipping, true, "enable TurboFan compiler on subset")
 DEFINE_BOOL(turbo_from_bytecode, false, "enable building graphs from bytecode")
@@ -484,7 +485,7 @@ DEFINE_BOOL(turbo_instruction_scheduling, false,
             "enable instruction scheduling in TurboFan")
 DEFINE_BOOL(turbo_stress_instruction_scheduling, false,
             "randomly schedule instructions to stress dependency tracking")
-DEFINE_BOOL(turbo_store_elimination, false,
+DEFINE_BOOL(turbo_store_elimination, true,
             "enable store-store elimination in TurboFan")
 
 // Flags for native WebAssembly.