Store arguments descriptor in ICData. Remove loading of arguments descriptor at unoptimized call si…

runtime/vm/flow_graph_compiler_x64.cc

Index: runtime/vm/flow_graph_compiler_x64.cc
===================================================================
--- runtime/vm/flow_graph_compiler_x64.cc	(revision 24207)
+++ runtime/vm/flow_graph_compiler_x64.cc	(working copy)
@@ -1002,7 +1002,8 @@
       function.IsClosureFunction() ? Symbols::Call().raw() : function.name());
   const int kNumArgsChecked = 1;
   const ICData& ic_data = ICData::ZoneHandle(
-      ICData::New(function, name, Isolate::kNoDeoptId, kNumArgsChecked));
+      ICData::New(function, name, Object::null_array(),
+                  Isolate::kNoDeoptId, kNumArgsChecked));
   __ LoadObject(RBX, ic_data);
   // RBP - 8 : PC marker, allows easy identification of RawInstruction obj.
   // RBP : points to previous frame pointer.
@@ -1173,7 +1174,7 @@
         // Invoke noSuchMethod function passing "call" as the function name.
         const int kNumArgsChecked = 1;
         const ICData& ic_data = ICData::ZoneHandle(
-            ICData::New(function, Symbols::Call(),
+            ICData::New(function, Symbols::Call(), Object::null_array(),
                         Isolate::kNoDeoptId, kNumArgsChecked));
         __ LoadObject(RBX, ic_data);
         // RBP - 8 : PC marker, for easy identification of RawInstruction obj.
@@ -1315,7 +1316,6 @@
 void FlowGraphCompiler::EmitOptimizedInstanceCall(
     ExternalLabel* target_label,
     const ICData& ic_data,
-    const Array& arguments_descriptor,
     intptr_t argument_count,
     intptr_t deopt_id,
     intptr_t token_pos,
@@ -1328,7 +1328,6 @@
   // Pass the function explicitly, it is used in IC stub.
   __ LoadObject(RDI, parsed_function().function());
   __ LoadObject(RBX, ic_data);
-  __ LoadObject(R10, arguments_descriptor);
   GenerateDartCall(deopt_id,
                    token_pos,
                    target_label,
@@ -1340,13 +1339,11 @@
 
 void FlowGraphCompiler::EmitInstanceCall(ExternalLabel* target_label,
                                          const ICData& ic_data,
-                                         const Array& arguments_descriptor,
                                          intptr_t argument_count,
                                          intptr_t deopt_id,
                                          intptr_t token_pos,
                                          LocationSummary* locs) {
   __ LoadObject(RBX, ic_data);
-  __ LoadObject(R10, arguments_descriptor);
   GenerateDartCall(deopt_id,
                    token_pos,
                    target_label,
@@ -1358,13 +1355,15 @@
 
 void FlowGraphCompiler::EmitMegamorphicInstanceCall(
     const ICData& ic_data,
-    const Array& arguments_descriptor,
     intptr_t argument_count,
     intptr_t deopt_id,
     intptr_t token_pos,
     LocationSummary* locs) {
   MegamorphicCacheTable* table = Isolate::Current()->megamorphic_cache_table();
   const String& name = String::Handle(ic_data.target_name());
+  const Array& arguments_descriptor =
+      Array::ZoneHandle(ic_data.arguments_descriptor());
+  ASSERT(!arguments_descriptor.IsNull());
   const MegamorphicCache& cache =
       MegamorphicCache::ZoneHandle(table->Lookup(name, arguments_descriptor));
   Label not_smi, load_cache;