[PATCH] arm64: LLVMLinux: Fix inline arm64 assembly for use with clang

Will Deacon will.deacon at arm.com
Mon Sep 8 03:53:07 PDT 2014


On Sat, Sep 06, 2014 at 12:24:20AM +0100, behanw at converseincode.com wrote:
> From: Mark Charlebois <charlebm at gmail.com>
> 
> Fix variable types for 64-bit inline assembly.
> 
> This patch now works with both gcc and clang.

Really? This looks like something the clang needs to do better on, as I
really don't see people adding these casts to future code. They're ugly and
redundant (or GCC).

This hunk:

> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index c555672..6894ef3 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -94,7 +94,7 @@ static int __init early_cachepolicy(char *p)
>  	 */
>  	asm volatile(
>  	"	mrs	%0, mair_el1\n"
> -	"	bfi	%0, %1, #%2, #8\n"
> +	"	bfi	%0, %1, %2, #8\n"
>  	"	msr	mair_el1, %0\n"
>  	"	isb\n"
>  	: "=&r" (tmp)

also looks fishy. Does gas accept that without the '#' prefix?

Will



More information about the linux-arm-kernel mailing list