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Subject: Re: [PATCH] Modify Aarch64 prologue analyzer to accept 128-bit registers
To: Andrew Pinski <pinskia@gmail.com>
CC: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
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From: Paul Carroll <pcarroll@codesourcery.com>
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(Sending again, due to problems with the mailing list not liking my 
previous post)

On 11/13/2017 12:32 PM, Andrew Pinski wrote:
> Hmm,  The normal elf aarch64 ABI says only 64bits is saved.  Is there
> another ABI which says 128bits of the SIMD register is saved?

Thanks for the comment, Andrew.
In this case, the code in question is an interrupt routine.
As such, it is not following the ABI, except when making calls itself.
When gdb processes the start of the interrupt routine, it finds the 
'stp' with the 128-bit register references and asserts.
That is a problem for debugging embedded applications, and is what this 
patch is trying to avoid.