Review for gcc-15/changes.html

[Heiko Eißfeldt]

> -      <li>FEAT_LRCPC2 (<code>+rcpc2</code>), enabled by default for
> +      <li>FEAT_RCPC2 (<code>+rcpc2</code>), enabled by default for
>
> and
>
> -    FEAT_LRCPC3 instructions, when support for the instructions is
> +    FEAT_RCPC3 instructions, when support for the instructions is
>
> These are incorrect.  The features really are FEAT_LRCPC2/3.
>
> Otherwise, I think these look generally like improvements.
>
> R.


That is interesting. I did a grep on gcc trunk for 'FEAT_.*RCPC' and got 
this
./gcc/common/config/aarch64/cpuinfo.h:  FEAT_RCPC,
./gcc/common/config/aarch64/cpuinfo.h:  FEAT_RCPC2,
./gcc/common/config/aarch64/cpuinfo.h:  FEAT_RCPC3,
./libgcc/config/aarch64/cpuinfo.c:    setCPUFeature(FEAT_RCPC);
./libgcc/config/aarch64/cpuinfo.c:    setCPUFeature(FEAT_RCPC2);
./libgcc/config/aarch64/cpuinfo.c:    setCPUFeature(FEAT_RCPC3);

Substring "LRCPC" I see only in conjunction with hardware capabilities 
but not features.

The documentation
(https://gcc.gnu.org/onlinedocs/gcc-15.1.0/gcc/AArch64-Options.html#aarch64-feature-modifiers)
lists in chapter 3.20.1.1 "-march and -mcpu Feature Modifiers"

‘rcpc’
‘rcpc2’
‘rcpc3’

Finally,  the substring LRCPC2 was not found in my repo at all.

H.