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

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

Index: src/full-codegen/ppc/full-codegen-ppc.cc
diff --git a/src/full-codegen/ppc/full-codegen-ppc.cc b/src/full-codegen/ppc/full-codegen-ppc.cc
index abd41c4c803f9a9c7e06778c589a6a67255d6f04..4af5bc4ab8f5afe2a0ca747794ac6356d38867f6 100644
--- a/src/full-codegen/ppc/full-codegen-ppc.cc
+++ b/src/full-codegen/ppc/full-codegen-ppc.cc
@@ -186,7 +186,7 @@ void FullCodeGenerator::Generate() {
     }
   }
 
-  bool function_in_register = true;
+  bool function_in_register_r4 = true;
 
   // Possibly allocate a local context.
   if (info->scope()->num_heap_slots() > 0) {
@@ -207,7 +207,7 @@ void FullCodeGenerator::Generate() {
       __ 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);
@@ -240,14 +240,19 @@ void FullCodeGenerator::Generate() {
     }
   }
 
+  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);
   }
@@ -271,6 +276,7 @@ void FullCodeGenerator::Generate() {
     __ 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(
@@ -298,6 +304,7 @@ void FullCodeGenerator::Generate() {
     __ 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);
@@ -309,7 +316,7 @@ void FullCodeGenerator::Generate() {
   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 {