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SubjectRe: x86/boot: Avoid using Intel mnemonics in AT&T syntax asm

* Peter Zijlstra <peterz@infradead.org> wrote:

>
> With 'GNU assembler (GNU Binutils for Debian) 2.39.90.20221231' the
> build now reports:
>
> arch/x86/realmode/rm/../../boot/bioscall.S: Assembler messages:
> arch/x86/realmode/rm/../../boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
> arch/x86/realmode/rm/../../boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
>
> arch/x86/boot/bioscall.S: Assembler messages:
> arch/x86/boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
> arch/x86/boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
>
> Which is due to:
>
> PR gas/29525
>
> Note that with the dropped CMPSD and MOVSD Intel Syntax string insn
> templates taking operands, mixed IsString/non-IsString template groups
> (with memory operands) cannot occur anymore. With that
> maybe_adjust_templates() becomes unnecessary (and is hence being
> removed).
>
> More details: https://sourceware.org/bugzilla/show_bug.cgi?id=29525
>
> Fixes: 7a734e7dd93b ("x86, setup: "glove box" BIOS calls -- infrastructure")
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> ---
> arch/x86/boot/bioscall.S | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> --- a/arch/x86/boot/bioscall.S
> +++ b/arch/x86/boot/bioscall.S
> @@ -32,7 +32,7 @@
> movw %dx, %si
> movw %sp, %di
> movw $11, %cx
> - rep; movsd
> + rep; movsl
>
> /* Pop full state from the stack */
> popal
> @@ -67,7 +67,7 @@
> jz 4f
> movw %sp, %si
> movw $11, %cx
> - rep; movsd
> + rep; movsl
> 4: addw $44, %sp

So I think the GAS change to introduce this warning was probably
unnecessary - these instructions weren't really causing any trouble and the
syntax was basically a legacy thing that shouldn't be touched - but I guess
that argument is water down the bridge now:

Reviewed-by: Ingo Molnar <mingo@kernel.org>

Thanks,

Ingo

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