[PATCH] Enable partial update depency breaking for A15

[Renato Golin]

On 26 March 2013 21:48, Silviu Baranga <Silviu.Baranga at arm.com> wrote:

> I should have added some comments to these tests (will do so tomorrow).
> The generated code uses a vld1.32 instruction to write the lane 1 of a D
> register
> containing the value of <2 x float> %B. Since the D register is defined,
> it would
> be incorrect to fully write it (with a vmov.f64) before the vld1.32
> instruction.
> Test checks that a vmov.f64 was not generated.
>

Oh, I see. Makes sense. That as a comment would be great in the test. ;)


It could be anything that writes the D register, it doesn't matter. The
> existing code uses a FCONSTD (vmov.f64) to write the D register before the
> vld1.32 instruction (or other instructions that partially update D
> registers)
> in order to break the existing dependencies on the D register.
>

That's what I though, ok. It'd be better to test for something a bit more
generic, since it could be many other types of VMOVs on D regs.

Maybe:

; CHECK: vmov{{.*}}d{{[0-9]+}},

or something. It also makes it more explicit what you're expecting, leaving
less need for a comment right before it.


Thanks!
--renato
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20130326/57a6beb6/attachment.html>