[PATCH] 19705 - -fno-branch-count-reg doesn't prevent decrement and branch instructions on a count register

[Jeff Law]

On 02/18/2016 08:39 PM, Martin Sebor wrote:
> Ping:
>
> https://gcc.gnu.org/ml/gcc-patches/2016-02/msg00809.html
>
> On 02/11/2016 02:58 PM, Martin Sebor wrote:
>> The more than decennnial rtl-optimization/19705 - -fno-branch-count-reg
>> doesn't prevent decrement and branch instructions on a count register
>> points out that the documentation of the option leads one to expect
>> that it prevents the decrement and branch instruction from appearing
>> in the instruction stream.  This isn't the case  The option prevents
>> a dedicated pass from running that introduces such instructions, but
>> it doesn't prevent other passes from introducing it.  The attached
>> updates the documentation to clarify this
I'm not even sure why we have this option to begin with.  One could 
easily argue that it's mis-named or should just go away.

In the mean time, your patch at least clarifies what it really does, so 
it's fine for the trunk.

jeff