RE: [PATCH] aarch64: Align lrcpc3 FEAT_STRING with /proc/cpuinfo 'Features' entry

[Kyrylo Tkachov <Kyrylo.Tkachov@arm.com>]

Hi Victor,

> -----Original Message-----
> From: Victor Do Nascimento <victor.donascimento@arm.com>
> Sent: Monday, March 25, 2024 10:59 AM
> To: gcc-patches@gcc.gnu.org
> Cc: Kyrylo Tkachov <Kyrylo.Tkachov@arm.com>; Richard Sandiford
> <Richard.Sandiford@arm.com>; Richard Earnshaw
> <Richard.Earnshaw@arm.com>; Victor Do Nascimento
> <Victor.DoNascimento@arm.com>
> Subject: [PATCH] aarch64: Align lrcpc3 FEAT_STRING with /proc/cpuinfo
> 'Features' entry
> 
> Due to the Linux kernel exposing the lrcpc3 architectural feature as
> "lrcpc3", this patch corrects the relevant FEATURE_STRING entry in the
> "rcpc3" AARCH64_OPT_FMV_EXTENSION macro, such that the feature can be
> correctly detected when doing native compilation on rcpc3-enabled
> targets.
> 
> Regtested on aarch64-linux-gnu.

Ok but...

> 
> gcc/ChangeLog:
> 
> 	* config/aarch64/aarch64-option-extensions.def: Fix 'lrcpc3'
> 	entry.

This would usually be written as:
	* config/aarch64/aarch64-option-extensions.def (rcpc3):
	Fix FEATURE_STRING field to "lrcpc3".

Thanks,
Kyrill

> 
> gcc/testsuite/ChangeLog:
> 
> 	* testsuite/gcc.target/aarch64/cpunative/info_24: New.
> 	* testsuite/gcc.target/aarch64/cpunative/native_cpu_24.c:
> 	Likewise.
> ---
>  gcc/config/aarch64/aarch64-option-extensions.def      |  2 +-
>  gcc/testsuite/gcc.target/aarch64/cpunative/info_24    |  8 ++++++++
>  .../gcc.target/aarch64/cpunative/native_cpu_24.c      | 11 +++++++++++
>  3 files changed, 20 insertions(+), 1 deletion(-)
>  create mode 100644 gcc/testsuite/gcc.target/aarch64/cpunative/info_24
>  create mode 100644
> gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_24.c
> 
> diff --git a/gcc/config/aarch64/aarch64-option-extensions.def
> b/gcc/config/aarch64/aarch64-option-extensions.def
> index 1a3b91c68cf..975e7b84cec 100644
> --- a/gcc/config/aarch64/aarch64-option-extensions.def
> +++ b/gcc/config/aarch64/aarch64-option-extensions.def
> @@ -174,7 +174,7 @@ AARCH64_OPT_FMV_EXTENSION("rcpc", RCPC, (), (), (),
> "lrcpc")
> 
>  AARCH64_FMV_FEATURE("rcpc2", RCPC2, (RCPC))
> 
> -AARCH64_OPT_FMV_EXTENSION("rcpc3", RCPC3, (), (), (), "rcpc3")
> +AARCH64_OPT_FMV_EXTENSION("rcpc3", RCPC3, (), (), (), "lrcpc3")
> 
>  AARCH64_FMV_FEATURE("frintts", FRINTTS, ())
> 
> diff --git a/gcc/testsuite/gcc.target/aarch64/cpunative/info_24
> b/gcc/testsuite/gcc.target/aarch64/cpunative/info_24
> new file mode 100644
> index 00000000000..8d3c16a1091
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/cpunative/info_24
> @@ -0,0 +1,8 @@
> +processor	: 0
> +BogoMIPS	: 100.00
> +Features	: fp asimd evtstrm aes pmull sha1 sha2 crc32 asimddp lrcpc3
> +CPU implementer	: 0xfe
> +CPU architecture: 8
> +CPU variant	: 0x0
> +CPU part	: 0xd08
> +CPU revision	: 2
> \ No newline at end of file
> diff --git a/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_24.c
> b/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_24.c
> new file mode 100644
> index 00000000000..05dc870885f
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/cpunative/native_cpu_24.c
> @@ -0,0 +1,11 @@
> +/* { dg-do compile { target { { aarch64*-*-linux*} && native } } } */
> +/* { dg-set-compiler-env-var GCC_CPUINFO
> "$srcdir/gcc.target/aarch64/cpunative/info_23" } */
> +/* { dg-additional-options "-mcpu=native --save-temps " } */
> +
> +int main()
> +{
> +  return 0;
> +}
> +
> +/* { dg-final { scan-assembler {\.arch armv8-a\+dotprod\+crc\+crypto\+rcpc3} }
> } */
> +/* Test one where rcpc3 is available and so should be emitted.  */
> --
> 2.34.1