[GROOVY-4764] duplicate checkcasts sometimes added

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Cannot Reproduce
• Affects Version/s: 1.8-rc-3
• Component/s: bytecode
• Assignee: Jochen Theodorou
• Reporter: Andy Clement
• Created: 05/Apr/11 11:43
• Updated: 01/Feb/12 13:04
• Resolved: 01/Feb/12 13:04

Description

Sometimes I see groovy is adding checkcasts twice in the bytecode. Here is a simple example:

Code.groovy:

java.lang.reflect.Field[] fs = Code.class.getDeclaredFields();

The bytecode looks like this:

public java.lang.Object run();
  Code:
   Stack=2, Locals=4, Args_size=1
   0:   invokestatic    #20; //Method $getCallSiteArray:()[Lorg/codehaus/groovy/runtime/callsite/CallSite;
   3:   astore_1
   4:   aload_1
   5:   ldc     #59; //int 1
   7:   aaload
   8:   invokestatic    #48; //Method $get$$class$Code:()Ljava/lang/Class;
   11:  invokeinterface #62,  2; //InterfaceMethod org/codehaus/groovy/runtime/callsite/CallSite.call:(Ljava/lang/Object;)Ljava/lang/Object;
   16:  astore_2
   17:  aload_2
   18:  invokestatic    #65; //Method $get$array$$class$java$lang$reflect$Field:()Ljava/lang/Class;
   21:  invokestatic    #69; //Method org/codehaus/groovy/runtime/ScriptBytecodeAdapter.castToType:(Ljava/lang/Object;Ljava/lang/Class;)Ljava/lang/Object;
   24:  checkcast       #71; //class "[Ljava/lang/reflect/Field;"
   27:  checkcast       #71; //class "[Ljava/lang/reflect/Field;"
   30:  astore_3
   31:  aload_2
   32:  areturn
   33:  aconst_null
   34:  areturn

I think I might be seeing it after every call to castToType.