Edgar E. Iglesias <edgar.igles...@gmail.com> writes: > On Thu, May 01, 2014 at 10:31:06AM +0100, Peter Maydell wrote: >> On 1 May 2014 10:02, Alex Bennée <alex.ben...@linaro.org> wrote: >> > >> > Edgar E. Iglesias <edgar.igles...@gmail.com> writes: >> > >> >> From: "Edgar E. Iglesias" <edgar.igles...@xilinx.com> >> >> >> >> For linked branches, updates to the link register happen >> >> conceptually after the read of the branch target register. >> >> >> >> Signed-off-by: Edgar E. Iglesias <edgar.igles...@xilinx.com> >> > >> > I'm trying to think of a case where this could actually cause a problem >> > but I can't. However from a clarity/correctness point of view it's >> > better. >> >> Well, we actually misexecute "BLR LR" otherwise, right? >> That's probably not very common but there's no reason it >> might not occur (eg call to a function pointer from a >> function where LR has been saved on entry and is free >> for use as a generic tempreg). > > Right. For example, the kernel/kvm actually does this in > arch/arm64/kvm/hyp.S:773: blr lr
Of course, I see know ;-) -- Alex Bennée
