Add a register allocation strategy compiler option

Test: manually, on device.

Change-Id: If007a1657dd5769ddef03691e0a19dbbe6ba1a29
diff --git a/compiler/driver/compiler_options.h b/compiler/driver/compiler_options.h
index 60b700a..cc66d7a 100644
--- a/compiler/driver/compiler_options.h
+++ b/compiler/driver/compiler_options.h
@@ -24,6 +24,7 @@
 #include "base/macros.h"
 #include "compiler_filter.h"
 #include "globals.h"
+#include "optimizing/register_allocator.h"
 #include "utils.h"
 
 namespace art {
@@ -74,7 +75,8 @@
                   bool abort_on_hard_verifier_failure,
                   const std::string& dump_cfg_file_name,
                   bool dump_cfg_append,
-                  bool force_determinism);
+                  bool force_determinism,
+                  RegisterAllocator::Strategy regalloc_strategy);
 
   CompilerFilter::Filter GetCompilerFilter() const {
     return compiler_filter_;
@@ -244,6 +246,10 @@
     return force_determinism_;
   }
 
+  RegisterAllocator::Strategy GetRegisterAllocationStrategy() const {
+    return register_allocation_strategy_;
+  }
+
  private:
   void ParseDumpInitFailures(const StringPiece& option, UsageFn Usage);
   void ParseDumpCfgPasses(const StringPiece& option, UsageFn Usage);
@@ -254,6 +260,7 @@
   void ParseSmallMethodMax(const StringPiece& option, UsageFn Usage);
   void ParseLargeMethodMax(const StringPiece& option, UsageFn Usage);
   void ParseHugeMethodMax(const StringPiece& option, UsageFn Usage);
+  void ParseRegisterAllocationStrategy(const StringPiece& option, UsageFn Usage);
 
   CompilerFilter::Filter compiler_filter_;
   size_t huge_method_threshold_;
@@ -297,6 +304,8 @@
   // outcomes.
   bool force_determinism_;
 
+  RegisterAllocator::Strategy register_allocation_strategy_;
+
   friend class Dex2Oat;
 
   DISALLOW_COPY_AND_ASSIGN(CompilerOptions);