x86 address generation / jump-targets

[Peter Helfer]

Hi all

I need to generate some return address, which is within a RuntimeStub I'm
creating. But the return address created as InternalAddress does show up as
0x00009BE9 - this seems not to be ok.. Is this the right approach ?

Regards, Peter





[do some stuff]
__ jmp(done)      // jumps over next segment

//==============================================

Label exitadapter;
        address returnpc_for_interpreter = __ pc();
        __ jmp(exitadapter); // jump over next segment

//==============================================


__ bind(done);
__ mov32(rcx, InternalAddress(returnpc_for_interpreter)); // lets hope we've
got the right one
__ xchg(rcx, Address(rbp, frame::return_addr_offset * wordSize) // replace
current returnpc with new one
... stackdump done here
__ jmp(rcx); // but still go once into the old entry..


//==============================================

__ bind(exitadapter);


// stack dump
        [AD759F30] = 0817BC00.%edi
        [AD759F34] = 00000000.%esi
        [AD759F38] = AD759F74.%ebp
        [AD759F3C] = AD759F50.%esp before pushad
        [AD759F40] = B7F7AFF4.%ebx
        [AD759F44] = 0817BC00.%edx
        [AD759F48] = B5C002B0.%ecx
        [AD759F4C] = D00DFACE.%eax
        [AD759F50] = ADBB36E8.
        [AD759F54] = AD759F54.
        [AD759F58] = B1D5506F.
        [AD759F5C] = AD759FA0.
        [AD759F60] = B1D55380.
        [AD759F64] = 00000000.
        [AD759F68] = B1D55188.
        [AD759F6C] = 00000000.
        [AD759F70] = B5C06752.
        [AD759F74] = AD759FA8 <-- rbp
        [AD759F78] = 00009BE9 <-- returnpc

.. and zeros after that..
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