[aarch64-port-dev ] C2 error on ARM sim only regardingcall to runtime from non-compiled code

[Andrew Haley]

On 10/04/2013 06:16 PM, Andrew Dinn wrote:
> 
> 
> On 04/10/13 18:05, Andrew Haley wrote:
>> On 10/04/2013 05:40 PM, Andrew Dinn wrote:
>>> (gdb) x/i OptoRuntime::new_array_nozero_C
>>>    0x7fb79f1f10 <OptoRuntime::new_array_nozero_C(Klass*, int,
>>> JavaThread*)>:  stp      x29, x30, [sp,#-128]!
>>>
>>> i.e the return address is at offset 128. 
>>
>> No it's not.  That's a predecrement with a writeback.
> 
> Hmm, not sure what the objection is here unless its that I omitted the
> direction of my 128.

Just sayin' that after that instruction executes, the return address
is just above the SP, not at offset 128.

> On Intel x29 is written at offset -8 (bytes) from the SP value in the
> anchor -- equivalently, offset 8 bytes from the value of SP when the
> routine is called.
> 
> That's where the frame code expects it (i evaluates _anchor._sp[-1]).
> 
> The above instruction writes x29 at offset -128 bytes from the value of
> SP when the routine is called i.e. not where the frame code expects it.

Sure, I get that.

Andrew.