Re: [PATCH] crc32-pclmul: remove useless relative addressing
From: Herbert Xu
Date: Sat Oct 07 2017 - 00:19:18 EST
On Wed, Sep 06, 2017 at 10:41:21PM -0400, Mikulas Patocka wrote:
> In 32-bit mode, the x86 architecture can hold full 32-bit pointers.
> Therefore, the code that copies the current address to the %ecx register
> and uses %ecx-relative addressing is useless, we could just use absolute
> addressing.
>
> The processors have a stack of return addresses for branch prediction. If
> we use a call instruction and pop the return address, it desynchronizes
> the return stack and causes branch prediction misses.
>
> This patch also moves the data to the .rodata section.
>
> Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Patch applied. Thanks.
--
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