First draft of the sh4 port

src/flag-definitions.h

Index: src/flag-definitions.h
diff --git a/src/flag-definitions.h b/src/flag-definitions.h
index 77e84ffa1e2ab00a371042fae5d68f15f8fa8988..61a905e1123364c0d0a8ae1fa9e1f0611b3680bf 100644
--- a/src/flag-definitions.h
+++ b/src/flag-definitions.h
@@ -167,7 +167,11 @@ DEFINE_bool(unbox_double_arrays, true, "automatically unbox arrays of doubles")
 DEFINE_bool(string_slices, true, "use string slices")
 
 // Flags for Crankshaft.
+#if defined(V8_TARGET_ARCH_SH4)
+DEFINE_bool(crankshaft, false, "use crankshaft")
+#else
 DEFINE_bool(crankshaft, true, "use crankshaft")
+#endif
 DEFINE_string(hydrogen_filter, "", "optimization filter")
 DEFINE_bool(use_range, true, "use hydrogen range analysis")
 DEFINE_bool(eliminate_dead_phis, true, "eliminate dead phis")
@@ -298,7 +302,7 @@ DEFINE_bool(enable_movw_movt, false,
 DEFINE_bool(enable_unaligned_accesses, true,
             "enable unaligned accesses for ARMv7 (ARM only)")
 DEFINE_bool(enable_fpu, true,
-            "enable use of MIPS FPU instructions if available (MIPS only)")
+            "enable use of FPU instructions if available (MIPS and SH4 only)")
 
 // bootstrapper.cc
 DEFINE_string(expose_natives_as, NULL, "expose natives in global object")