Revert "Lazy deopt without code patching."

runtime/vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1105 matching lines @@
     }
   }
 
   EndCodeSourceRange(TokenPosition::kDartCodePrologue);
   ASSERT(!block_order().is_empty());
   VisitBlocks();
 
   __ int3();
   ASSERT(assembler()->constant_pool_allowed());
   GenerateDeferredCode();
+  // Emit function patching code. This will be swapped with the first 13 bytes
+  // at entry point.
+
+  BeginCodeSourceRange();
+  if (is_optimizing() && !FLAG_precompiled_mode) {
+    // Leave enough space for patching in case of lazy deoptimization.
+    __ nop(ShortCallPattern::pattern_length_in_bytes());
+    lazy_deopt_return_pc_offset_ = assembler()->CodeSize();
+    __ Jmp(*StubCode::DeoptimizeLazyFromReturn_entry(), PP);
+    lazy_deopt_throw_pc_offset_ = assembler()->CodeSize();
+    __ Jmp(*StubCode::DeoptimizeLazyFromThrow_entry(), PP);
+  }
+  EndCodeSourceRange(TokenPosition::kDartCodeEpilogue);
 }
 
 
 void FlowGraphCompiler::GenerateCall(TokenPosition token_pos,
                                      const StubEntry& stub_entry,
                                      RawPcDescriptors::Kind kind,
                                      LocationSummary* locs) {
   __ Call(stub_entry);
   AddCurrentDescriptor(kind, Thread::kNoDeoptId, token_pos);
   RecordSafepoint(locs);
@@ skipping 704 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(kFpuRegisterSize));
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64