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Re: predicated instructions in ARM


On Thu, May 02, 2002 at 02:03:10PM -0700, Arvind Krishnaswamy wrote:
> Isn't it better to just use branches to the appropriate code
> since branches will introduce just 1 stall in the pipeline?

There's a back-end setting that says how many instructions
we may convert instead of using a branch.  Whether or not it
is set correctly is something you'd have to ask the ARM port
maintainers.

> One more question. In the above code, control is never transferred to .L11
> or .L12. Why are these labels introduced?

Depending on which compiler version you're looking at, the
if-conversion is done in either the generic part of the 
compiler (in which case those labels will be there iff they
are used), or in the ARM backend as peepholes, in which case
it's too late to remove the labels.


r~


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