Re: [PATCH v10 2/6] x86: Update memrchr to use new VEC macros

[Sunil Pandey <skpgkp2@gmail.com>]

On Fri, Oct 14, 2022 at 8:01 PM Noah Goldstein via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> Replace %VEC(n) -> %VMM(n)
>
> This commit does not change libc.so
>
> Tested build on x86-64
> ---
>  sysdeps/x86_64/multiarch/memrchr-evex.S | 42 ++++++++++++-------------
>  1 file changed, 21 insertions(+), 21 deletions(-)
>
> diff --git a/sysdeps/x86_64/multiarch/memrchr-evex.S b/sysdeps/x86_64/multiarch/memrchr-evex.S
> index ea3a0a0a60..550b328c5a 100644
> --- a/sysdeps/x86_64/multiarch/memrchr-evex.S
> +++ b/sysdeps/x86_64/multiarch/memrchr-evex.S
> @@ -21,7 +21,7 @@
>  #if ISA_SHOULD_BUILD (4)
>
>  # include <sysdep.h>
> -# include "evex256-vecs.h"
> +# include "x86-evex256-vecs.h"
>  # if VEC_SIZE != 32
>  #  error "VEC_SIZE != 32 unimplemented"
>  # endif
> @@ -31,7 +31,7 @@
>  # endif
>
>  # define PAGE_SIZE                     4096
> -# define VECMATCH                      VEC(0)
> +# define VMMMATCH                      VMM(0)
>
>         .section SECTION(.text), "ax", @progbits
>  ENTRY_P2ALIGN(MEMRCHR, 6)
> @@ -47,7 +47,7 @@ ENTRY_P2ALIGN(MEMRCHR, 6)
>            correct page cross check and 2) it correctly sets up end ptr to be
>            subtract by lzcnt aligned.  */
>         leaq    -1(%rdi, %rdx), %rax
> -       vpbroadcastb %esi, %VECMATCH
> +       vpbroadcastb %esi, %VMMMATCH
>
>         /* Check if we can load 1x VEC without cross a page.  */
>         testl   $(PAGE_SIZE - VEC_SIZE), %eax
> @@ -55,7 +55,7 @@ ENTRY_P2ALIGN(MEMRCHR, 6)
>
>         /* Don't use rax for pointer here because EVEX has better encoding with
>            offset % VEC_SIZE == 0.  */
> -       vpcmpb  $0, -(VEC_SIZE)(%rdi, %rdx), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE)(%rdi, %rdx), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         /* Fall through for rdx (len) <= VEC_SIZE (expect small sizes).  */
> @@ -96,7 +96,7 @@ L(more_1x_vec):
>         movq    %rax, %rdx
>
>         /* Need no matter what.  */
> -       vpcmpb  $0, -(VEC_SIZE)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         subq    %rdi, %rdx
> @@ -115,7 +115,7 @@ L(last_2x_vec):
>
>         /* Don't use rax for pointer here because EVEX has better encoding with
>            offset % VEC_SIZE == 0.  */
> -       vpcmpb  $0, -(VEC_SIZE * 2)(%rdi, %rdx), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE * 2)(%rdi, %rdx), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>         /* NB: 64-bit lzcnt. This will naturally add 32 to position.  */
>         lzcntq  %rcx, %rcx
> @@ -131,7 +131,7 @@ L(last_2x_vec):
>  L(page_cross):
>         movq    %rax, %rsi
>         andq    $-VEC_SIZE, %rsi
> -       vpcmpb  $0, (%rsi), %VECMATCH, %k0
> +       vpcmpb  $0, (%rsi), %VMMMATCH, %k0
>         kmovd   %k0, %r8d
>         /* Shift out negative alignment (because we are starting from endptr and
>            working backwards).  */
> @@ -165,13 +165,13 @@ L(more_2x_vec):
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x0_dec)
>
> -       vpcmpb  $0, -(VEC_SIZE * 2)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE * 2)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x1)
>
>         /* Need no matter what.  */
> -       vpcmpb  $0, -(VEC_SIZE * 3)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE * 3)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         subq    $(VEC_SIZE * 4), %rdx
> @@ -185,7 +185,7 @@ L(last_vec):
>
>
>         /* Need no matter what.  */
> -       vpcmpb  $0, -(VEC_SIZE * 4)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE * 4)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>         lzcntl  %ecx, %ecx
>         subq    $(VEC_SIZE * 3 + 1), %rax
> @@ -220,7 +220,7 @@ L(more_4x_vec):
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x2)
>
> -       vpcmpb  $0, -(VEC_SIZE * 4)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, -(VEC_SIZE * 4)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         testl   %ecx, %ecx
> @@ -243,17 +243,17 @@ L(more_4x_vec):
>  L(loop_4x_vec):
>         /* Store 1 were not-equals and 0 where equals in k1 (used to mask later
>            on).  */
> -       vpcmpb  $4, (VEC_SIZE * 3)(%rax), %VECMATCH, %k1
> +       vpcmpb  $4, (VEC_SIZE * 3)(%rax), %VMMMATCH, %k1
>
>         /* VEC(2/3) will have zero-byte where we found a CHAR.  */
> -       vpxorq  (VEC_SIZE * 2)(%rax), %VECMATCH, %VEC(2)
> -       vpxorq  (VEC_SIZE * 1)(%rax), %VECMATCH, %VEC(3)
> -       vpcmpb  $0, (VEC_SIZE * 0)(%rax), %VECMATCH, %k4
> +       vpxorq  (VEC_SIZE * 2)(%rax), %VMMMATCH, %VMM(2)
> +       vpxorq  (VEC_SIZE * 1)(%rax), %VMMMATCH, %VMM(3)
> +       vpcmpb  $0, (VEC_SIZE * 0)(%rax), %VMMMATCH, %k4
>
>         /* Combine VEC(2/3) with min and maskz with k1 (k1 has zero bit where
>            CHAR is found and VEC(2/3) have zero-byte where CHAR is found.  */
> -       vpminub %VEC(2), %VEC(3), %VEC(3){%k1}{z}
> -       vptestnmb %VEC(3), %VEC(3), %k2
> +       vpminub %VMM(2), %VMM(3), %VMM(3){%k1}{z}
> +       vptestnmb %VMM(3), %VMM(3), %k2
>
>         /* Any 1s and we found CHAR.  */
>         kortestd %k2, %k4
> @@ -270,7 +270,7 @@ L(loop_4x_vec):
>  L(last_4x_vec):
>
>         /* Used no matter what.  */
> -       vpcmpb  $0, (VEC_SIZE * -1)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, (VEC_SIZE * -1)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         cmpl    $(VEC_SIZE * 2), %edx
> @@ -280,14 +280,14 @@ L(last_4x_vec):
>         jnz     L(ret_vec_x0_dec)
>
>
> -       vpcmpb  $0, (VEC_SIZE * -2)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, (VEC_SIZE * -2)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x1)
>
>         /* Used no matter what.  */
> -       vpcmpb  $0, (VEC_SIZE * -3)(%rax), %VECMATCH, %k0
> +       vpcmpb  $0, (VEC_SIZE * -3)(%rax), %VMMMATCH, %k0
>         kmovd   %k0, %ecx
>
>         cmpl    $(VEC_SIZE * 3), %edx
> @@ -309,7 +309,7 @@ L(loop_end):
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x0_end)
>
> -       vptestnmb %VEC(2), %VEC(2), %k0
> +       vptestnmb %VMM(2), %VMM(2), %k0
>         kmovd   %k0, %ecx
>         testl   %ecx, %ecx
>         jnz     L(ret_vec_x1_end)
> --
> 2.34.1
>

LGTM

--Sunil