[PATCH] cipher: Fix SM3 avx/bmi2 compilation error

[Jussi Kivilinna]

Hello,

On 20.12.2021 5.23, Tianjia Zhang via Gcrypt-devel wrote:
> * cipher/sm3-avx-bmi2-amd64.S: Fix assembler errors.
> 
> --
> 
> There are a lot of the following errors compiling with GNU assembler
> version 2.27-41:
> 
>    sm3-avx-bmi2-amd64.S: Assembler messages:
>    sm3-avx-bmi2-amd64.S:402: Error: 0xf3988a32 out range of signed
>      32bit displacement
> 
> The newer GNU assembler does not have this issue. It is likely that
> the old version of the assembler did not handle it well, but in order
> to allow libgcrypt to be compiled on more systems, I still fixed this
> problem, an additional add operation is added to the lea instruction
> to calculate the sum of three elements. I did a benchmark test on an
> Intel i5-6200U 2.30GHz CPU and found no significant performance
> difference.


Thanks for reporting. However, I think this can be fixed by changing
K0-K63 macros from hex-format to signed decimal values. Patch attached.

> 
> Signed-off-by: Tianjia Zhang <tianjia.zhang at linux.alibaba.com>
> ---
>   cipher/sm3-avx-bmi2-amd64.S | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/cipher/sm3-avx-bmi2-amd64.S b/cipher/sm3-avx-bmi2-amd64.S
> index 93aecacb..4a075d76 100644
> --- a/cipher/sm3-avx-bmi2-amd64.S
> +++ b/cipher/sm3-avx-bmi2-amd64.S
> @@ -206,7 +206,8 @@ ELF(.size _gcry_sm3_avx2_consts,.-_gcry_sm3_avx2_consts)
>           /* rol(a, 12) => t0 */ \
>             roll3mov(12, a, t0); /* rorxl here would reduce perf by 6% on zen3 */ \
>           /* rol (t0 + e + t), 7) => t1 */ \
> -          leal K##round(t0, e, 1), t1; \
> +          addl3(t0, e, t1); \
> +          addl $K##round, t1; \

This is 12% slower on AMD Zen3 (from 7.37 cycles/byte to 8.30 cpb).

-Jussi

>             roll2(7, t1); \
>           /* h + w1 => h */ \
>             addl wtype##_W1_ADDR(round, widx), h; \
> 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-sm3-avx-bmi2-amd64-fix-issue-with-LEA-and-32-bit-uns.patch
Type: text/x-patch
Size: 4044 bytes
Desc: not available
URL: <https://lists.gnupg.org/pipermail/gcrypt-devel/attachments/20211220/450f8d3c/attachment.bin>