Refactor generating lazy deoptimization descriptors.

runtime/vm/flow_graph_compiler.cc

Index: runtime/vm/flow_graph_compiler.cc
===================================================================
--- runtime/vm/flow_graph_compiler.cc	(revision 40150)
+++ runtime/vm/flow_graph_compiler.cc	(working copy)
@@ -541,13 +541,16 @@
 
 
 void FlowGraphCompiler::AddDeoptIndexAtCall(intptr_t deopt_id,
-                                            intptr_t token_pos) {
+                                            intptr_t token_pos,
+                                            intptr_t input_count) {
   ASSERT(is_optimizing());
   ASSERT(!intrinsic_mode());
+  Environment* env = pending_deoptimization_env_->DeepCopy(
+      isolate(), pending_deoptimization_env_->Length() - input_count);
   CompilerDeoptInfo* info =
       new CompilerDeoptInfo(deopt_id,
                             ICData::kDeoptAtCall,
-                            pending_deoptimization_env_);
+                            env);
   info->set_pc_offset(assembler()->CodeSize());
   deopt_infos_.Add(info);
 }
@@ -872,6 +875,29 @@
 }
 
 
+// Record safe point and deoptimization info if applicable.
+void FlowGraphCompiler::RecordCallInfo(intptr_t token_pos,
+                                       RawPcDescriptors::Kind kind,
+                                       intptr_t deopt_id,
+                                       LocationSummary* locs,
+                                       intptr_t input_count_adjustment) {
+  AddCurrentDescriptor(kind, deopt_id, token_pos);
+  RecordSafepoint(locs);
+  if (deopt_id != Isolate::kNoDeoptId) {
+    // Marks either the continuation point in unoptimized code or the
+    // deoptimization point in optimized code, after call.
+    const intptr_t deopt_id_after = Isolate::ToDeoptAfter(deopt_id);
+    if (is_optimizing()) {
+      AddDeoptIndexAtCall(deopt_id_after, token_pos, input_count_adjustment);
+    } else {
+      // Add deoptimization continuation point after the call and before the
+      // arguments are removed.
+      AddCurrentDescriptor(RawPcDescriptors::kDeopt, deopt_id_after, token_pos);
+    }
+  }
+}
+
+
 void FlowGraphCompiler::GenerateInstanceCall(
     intptr_t deopt_id,
     intptr_t token_pos,