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

src/full-codegen/ppc/full-codegen-ppc.cc

 // Copyright 2014 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_PPC
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/compiler.h"
@@ skipping 168 matching lines @@
         __ bdnz(&loop_header);
       }
       int remaining = locals_count % kMaxPushes;
       // Emit the remaining pushes.
       for (int i = 0; i < remaining; i++) {
         __ push(ip);
       }
     }
   }
 
-  bool function_in_register = true;
+  bool function_in_register_r4 = true;
 
   // Possibly allocate a local context.
   if (info->scope()->num_heap_slots() > 0) {
     // Argument to NewContext is the function, which is still in r4.
     Comment cmnt(masm_, "[ Allocate context");
     bool need_write_barrier = true;
     int slots = info->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
     if (info->scope()->is_script_scope()) {
       __ push(r4);
       __ Push(info->scope()->GetScopeInfo(info->isolate()));
       __ CallRuntime(Runtime::kNewScriptContext, 2);
     } 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(r4);
       __ CallRuntime(Runtime::kNewFunctionContext, 1);
     }
-    function_in_register = false;
+    function_in_register_r4 = false;
     // Context is returned in r3.  It replaces the context passed to us.
     // It's saved in the stack and kept live in cp.
     __ mr(cp, r3);
     __ StoreP(r3, MemOperand(fp, StandardFrameConstants::kContextOffset));
     // Copy any necessary parameters into the context.
     int num_parameters = info->scope()->num_parameters();
     int first_parameter = info->scope()->has_this_declaration() ? -1 : 0;
     for (int i = first_parameter; i < num_parameters; i++) {
       Variable* var = (i == -1) ? scope()->receiver() : scope()->parameter(i);
       if (var->IsContextSlot()) {
@@ skipping 12 matching lines @@
         } else if (FLAG_debug_code) {
           Label done;
           __ JumpIfInNewSpace(cp, r3, &done);
           __ Abort(kExpectedNewSpaceObject);
           __ bind(&done);
         }
       }
     }
   }
 
+  PrepareForBailoutForId(BailoutId::Prologue(), NO_REGISTERS);
+  // Function register is trashed in case we bailout here. But since that
+  // could happen only when we allocate a context the value of
+  // |function_in_register_r4| is correct.
+
   // Possibly set up a local binding to the this function which is used in
   // derived constructors with super calls.
   Variable* this_function_var = scope()->this_function_var();
   if (this_function_var != nullptr) {
     Comment cmnt(masm_, "[ This function");
-    if (!function_in_register) {
+    if (!function_in_register_r4) {
       __ LoadP(r4, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-      // The write barrier clobbers register again, keep is marked as such.
+      // The write barrier clobbers register again, keep it marked as such.
     }
     SetVar(this_function_var, r4, r3, r5);
   }
 
   Variable* new_target_var = scope()->new_target_var();
   if (new_target_var != nullptr) {
     Comment cmnt(masm_, "[ new.target");
 
     // Get the frame pointer for the calling frame.
     __ LoadP(r5, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
 
     // Skip the arguments adaptor frame if it exists.
     __ LoadP(r4, MemOperand(r5, StandardFrameConstants::kContextOffset));
     __ CmpSmiLiteral(r4, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
     Label skip;
     __ bne(&skip);
     __ LoadP(r5, MemOperand(r5, StandardFrameConstants::kCallerFPOffset));
     __ bind(&skip);
 
     // Check the marker in the calling frame.
     __ LoadP(r4, MemOperand(r5, StandardFrameConstants::kMarkerOffset));
     __ CmpSmiLiteral(r4, Smi::FromInt(StackFrame::CONSTRUCT), r0);
     Label non_construct_frame, done;
+    function_in_register_r4 = false;
 
     __ bne(&non_construct_frame);
     __ LoadP(r3, MemOperand(
                      r5, ConstructFrameConstants::kOriginalConstructorOffset));
     __ b(&done);
 
     __ bind(&non_construct_frame);
     __ LoadRoot(r3, Heap::kUndefinedValueRootIndex);
     __ bind(&done);
 
     SetVar(new_target_var, r3, r5, r6);
   }
 
   // Possibly allocate RestParameters
   int rest_index;
   Variable* rest_param = scope()->rest_parameter(&rest_index);
   if (rest_param) {
     Comment cmnt(masm_, "[ Allocate rest parameter array");
 
     int num_parameters = info->scope()->num_parameters();
     int offset = num_parameters * kPointerSize;
 
     __ addi(r6, fp, Operand(StandardFrameConstants::kCallerSPOffset + offset));
     __ LoadSmiLiteral(r5, Smi::FromInt(num_parameters));
     __ LoadSmiLiteral(r4, Smi::FromInt(rest_index));
     __ LoadSmiLiteral(r3, Smi::FromInt(language_mode()));
     __ Push(r6, r5, r4, r3);
+    function_in_register_r4 = false;
 
     RestParamAccessStub stub(isolate());
     __ CallStub(&stub);
 
     SetVar(rest_param, r3, r4, r5);
   }
 
   Variable* arguments = scope()->arguments();
   if (arguments != NULL) {
     // Function uses arguments object.
     Comment cmnt(masm_, "[ Allocate arguments object");
-    if (!function_in_register) {
+    if (!function_in_register_r4) {
       // Load this again, if it's used by the local context below.
       __ LoadP(r6, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
     } else {
       __ mr(r6, r4);
     }
     // Receiver is just before the parameters on the caller's stack.
     int num_parameters = info->scope()->num_parameters();
     int offset = num_parameters * kPointerSize;
     __ addi(r5, fp, Operand(StandardFrameConstants::kCallerSPOffset + offset));
     __ LoadSmiLiteral(r4, Smi::FromInt(num_parameters));
@@ skipping 4992 matching lines @@
     return ON_STACK_REPLACEMENT;
   }
 
   DCHECK(interrupt_address ==
          isolate->builtins()->OsrAfterStackCheck()->entry());
   return OSR_AFTER_STACK_CHECK;
 }
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_PPC