Thu, 07 Apr 2011 09:53:20 -0700
7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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25 #ifndef CPU_SPARC_VM_INTERPRETERRT_SPARC_HPP
26 #define CPU_SPARC_VM_INTERPRETERRT_SPARC_HPP
28 #include "memory/allocation.hpp"
30 static int binary_search(int key, LookupswitchPair* array, int n);
32 static address iload (JavaThread* thread);
33 static address aload (JavaThread* thread);
34 static address istore(JavaThread* thread);
35 static address astore(JavaThread* thread);
36 static address iinc (JavaThread* thread);
40 // native method calls
42 class SignatureHandlerGenerator: public NativeSignatureIterator {
43 private:
44 MacroAssembler* _masm;
46 void pass_word(int size_of_arg, int offset_in_arg);
47 void pass_int() { pass_word(1, 0); }
48 void pass_long();
49 void pass_double();
50 void pass_float();
51 void pass_object();
53 public:
54 // Creation
55 SignatureHandlerGenerator(methodHandle method, CodeBuffer* buffer) : NativeSignatureIterator(method) {
56 _masm = new MacroAssembler(buffer);
57 }
59 // Code generation
60 void generate( uint64_t fingerprint );
61 };
63 #endif // CPU_SPARC_VM_INTERPRETERRT_SPARC_HPP