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Subject: Re: [Qemu-devel] [RFC 01/10] target-arm: protect cpu_exclusive_*.
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To: "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Mark Burton <mark.burton@greensocs.com>
Cc: mttcg@greensocs.com, Peter Maydell <peter.maydell@linaro.org>, "J. Kiszka" <jan.kiszka@siemens.com>, QEMU Developers <qemu-devel@nongnu.org>, Alexander Graf <agraf@suse.de>, Paolo Bonzini <pbonzini@redhat.com>, KONRAD Fr?d?ric <fred.konrad@greensocs.com>

On 03/03/2015 07:47 AM, Dr. David Alan Gilbert wrote:
> That works for ARM where you have to terminate a ldrex with a strex or clrex,
> but not all architectures have the equivalent of a clrex; most as I remember
> just let you do an ldrex equivalent, decide you don't want to do the strex equivalent
> and get on with life.


I'm pretty sure that's not the case.  In fact, I can guarantee you that GCC
never issues clrex, but does in fact simply do nothing like you describe for
other architectures if we decide not to do the store.


r~