Crankshaft is now able to compile top level code even if there is a ScriptContext.

src/x64/lithium-codegen-x64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/cpu-profiler.h"
@@ skipping 167 matching lines @@
       __ subp(rsp, Immediate(slots * kPointerSize));
 #ifdef _MSC_VER
       MakeSureStackPagesMapped(slots * kPointerSize);
 #endif
     }
 
     if (info()->saves_caller_doubles()) {
       SaveCallerDoubles();
     }
   }
+  return !is_aborted();
+}
+
+
+void LCodeGen::DoPrologue(LPrologue* instr) {
+  Comment(";;; Prologue begin");
 
   // Possibly allocate a local context.
-  int heap_slots = info_->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
-  if (heap_slots > 0) {
+  if (info_->num_heap_slots() > 0) {
     Comment(";;; Allocate local context");
     bool need_write_barrier = true;
     // Argument to NewContext is the function, which is still in rdi.
-    DCHECK(!info()->scope()->is_script_scope());
-    if (heap_slots <= FastNewContextStub::kMaximumSlots) {
-      FastNewContextStub stub(isolate(), heap_slots);
+    int slots = info_->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
+    Safepoint::DeoptMode deopt_mode = Safepoint::kNoLazyDeopt;
+    if (info()->scope()->is_script_scope()) {
+      __ Push(rdi);
+      __ Push(info()->scope()->GetScopeInfo(info()->isolate()));
+      __ CallRuntime(Runtime::kNewScriptContext, 2);
+      deopt_mode = Safepoint::kLazyDeopt;
+    } else if (slots <= FastNewContextStub::kMaximumSlots) {
+      FastNewContextStub stub(isolate(), slots);
       __ CallStub(&stub);
       // Result of FastNewContextStub is always in new space.
       need_write_barrier = false;
     } else {
       __ Push(rdi);
       __ CallRuntime(Runtime::kNewFunctionContext, 1);
     }
-    RecordSafepoint(Safepoint::kNoLazyDeopt);
+    RecordSafepoint(deopt_mode);
+
     // Context is returned in rax.  It replaces the context passed to us.
     // It's saved in the stack and kept live in rsi.
     __ movp(rsi, rax);
     __ movp(Operand(rbp, StandardFrameConstants::kContextOffset), rax);
 
     // Copy any necessary parameters into the context.
     int num_parameters = scope()->num_parameters();
     int first_parameter = scope()->has_this_declaration() ? -1 : 0;
     for (int i = first_parameter; i < num_parameters; i++) {
       Variable* var = (i == -1) ? scope()->receiver() : scope()->parameter(i);
@@ skipping 12 matching lines @@
           Label done;
           __ JumpIfInNewSpace(rsi, rax, &done, Label::kNear);
           __ Abort(kExpectedNewSpaceObject);
           __ bind(&done);
         }
       }
     }
     Comment(";;; End allocate local context");
   }
 
-  // Trace the call.
-  if (FLAG_trace && info()->IsOptimizing()) {
-    __ CallRuntime(Runtime::kTraceEnter, 0);
-  }
-  return !is_aborted();
+  Comment(";;; Prologue end");
 }
 
 
 void LCodeGen::GenerateOsrPrologue() {
   // Generate the OSR entry prologue at the first unknown OSR value, or if there
   // are none, at the OSR entrypoint instruction.
   if (osr_pc_offset_ >= 0) return;
 
   osr_pc_offset_ = masm()->pc_offset();
 
@@ skipping 5684 matching lines @@
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64