First simplistic implementation of escape analysis.

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index 91186defe4737774362661fba2f130888d3311ad..b07354a5e59f8d2061354e5c54aa2292d5ad7aec 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -214,6 +214,7 @@ DEFINE_bool(use_range, true, "use hydrogen range analysis")
 DEFINE_bool(use_gvn, true, "use hydrogen global value numbering")
 DEFINE_bool(use_canonicalizing, true, "use hydrogen instruction canonicalizing")
 DEFINE_bool(use_inlining, true, "use function inlining")
+DEFINE_bool(use_escape_analysis, false, "use hydrogen escape analysis")
 DEFINE_int(max_inlined_source_size, 600,
            "maximum source size in bytes considered for a single inlining")
 DEFINE_int(max_inlined_nodes, 196,
@@ -234,6 +235,7 @@ DEFINE_bool(trace_all_uses, false, "trace all use positions")
 DEFINE_bool(trace_range, false, "trace range analysis")
 DEFINE_bool(trace_gvn, false, "trace global value numbering")
 DEFINE_bool(trace_representation, false, "trace representation types")
+DEFINE_bool(trace_escape_analysis, false, "trace hydrogen escape analysis")
 DEFINE_bool(trace_track_allocation_sites, false,
             "trace the tracking of allocation sites")
 DEFINE_bool(trace_migration, false, "trace object migration")