PPC/s390: [interpreter] Fix self-healing with preserved bytecode.

src/builtins/ppc/builtins-ppc.cc

Index: src/builtins/ppc/builtins-ppc.cc
diff --git a/src/builtins/ppc/builtins-ppc.cc b/src/builtins/ppc/builtins-ppc.cc
index b799819dbdf71b5af1394eb4079d63761213bddb..af1e624ca07f8a2a9e2d13eab015852dae0b23e8 100644
--- a/src/builtins/ppc/builtins-ppc.cc
+++ b/src/builtins/ppc/builtins-ppc.cc
@@ -1077,11 +1077,14 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
            FieldMemOperand(debug_info, DebugInfo::kDebugBytecodeArrayIndex));
   __ bind(&array_done);
 
+  // Check whether we should continue to use the interpreter.
+  Label switch_to_different_code_kind;
+  __ LoadP(r3, FieldMemOperand(r3, SharedFunctionInfo::kCodeOffset));
+  __ mov(ip, Operand(masm->CodeObject()));  // Self-reference to this code.
+  __ cmp(r3, ip);
+  __ bne(&switch_to_different_code_kind);
+
   // Check function data field is actually a BytecodeArray object.
-  Label bytecode_array_not_present;
-  __ CompareRoot(kInterpreterBytecodeArrayRegister,
-                 Heap::kUndefinedValueRootIndex);
-  __ beq(&bytecode_array_not_present);
 
   if (FLAG_debug_code) {
     __ TestIfSmi(kInterpreterBytecodeArrayRegister, r0);
@@ -1146,10 +1149,10 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   LeaveInterpreterFrame(masm, r5);
   __ blr();
 
-  // If the bytecode array is no longer present, then the underlying function
-  // has been switched to a different kind of code and we heal the closure by
-  // switching the code entry field over to the new code object as well.
-  __ bind(&bytecode_array_not_present);
+  // If the shared code is no longer this entry trampoline, then the underlying
+  // function has been switched to a different kind of code and we heal the
+  // closure by switching the code entry field over to the new code as well.
+  __ bind(&switch_to_different_code_kind);
   __ LeaveFrame(StackFrame::JAVA_SCRIPT);
   __ LoadP(r7, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
   __ LoadP(r7, FieldMemOperand(r7, SharedFunctionInfo::kCodeOffset));