Re: [PATCH] crypto: blake2b - Fix clang optimization for ARMv7-M

From: Herbert Xu
Date: Fri May 15 2020 - 02:22:07 EST


On Tue, May 05, 2020 at 03:53:45PM +0200, Arnd Bergmann wrote:
> When building for ARMv7-M, clang-9 or higher tries to unroll some loops,
> which ends up confusing the register allocator to the point of generating
> rather bad code and using more than the warning limit for stack frames:
>
> warning: stack frame size of 1200 bytes in function 'blake2b_compress' [-Wframe-larger-than=]
>
> Forcing it to not unroll the final loop avoids this problem.
>
> Fixes: 91d689337fe8 ("crypto: blake2b - add blake2b generic implementation")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> crypto/blake2b_generic.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)

Patch applied. Thanks.
--
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