On Tue, Sep 15, 2020 at 2:46 AM Ard Biesheuvel <ardb@xxxxxxxxxx> wrote:
>
> The ADRL pseudo instruction is not an architectural construct, but a
> convenience macro that was supported by the ARM proprietary assembler
> and adopted by binutils GAS as well, but only when assembling in 32-bit
> ARM mode. Therefore, it can only be used in assembler code that is known
> to assemble in ARM mode only, but as it turns out, the Clang assembler
> does not implement ADRL at all, and so it is better to get rid of it
> entirely.
>
> So replace the ADRL instruction with a ADR instruction that refers to
> a nearer symbol, and apply the delta explicitly using an additional
> instruction.
>
> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> Cc: Stefan Agner <stefan@xxxxxxxx>
> Cc: Peter Smith <Peter.Smith@xxxxxxx>
> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> ---
> I will leave it to the Clang folks to decide whether this needs to be
> backported and how far, but a Cc stable seems reasonable here.
>
> arch/arm/crypto/sha256-armv4.pl | 4 ++--
> arch/arm/crypto/sha256-core.S_shipped | 4 ++--
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/crypto/sha256-armv4.pl b/arch/arm/crypto/sha256-armv4.pl
> index 9f96ff48e4a8..8aeb2e82f915 100644
> --- a/arch/arm/crypto/sha256-armv4.pl
> +++ b/arch/arm/crypto/sha256-armv4.pl
> @@ -175,7 +175,6 @@ $code=<<___;
> #else
> .syntax unified
> # ifdef __thumb2__
> -# define adrl adr
> .thumb
> # else
> .code 32
> @@ -471,7 +470,8 @@ sha256_block_data_order_neon:
> stmdb sp!,{r4-r12,lr}
>
> sub $H,sp,#16*4+16
> - adrl $Ktbl,K256
> + adr $Ktbl,.Lsha256_block_data_order
> + add $Ktbl,$Ktbl,#K256-.Lsha256_block_data_order
> bic $H,$H,#15 @ align for 128-bit stores
> mov $t2,sp
> mov sp,$H @ alloca
> diff --git a/arch/arm/crypto/sha256-core.S_shipped b/arch/arm/crypto/sha256-core.S_shipped
> index ea04b2ab0c33..1861c4e8a5ba 100644
> --- a/arch/arm/crypto/sha256-core.S_shipped
> +++ b/arch/arm/crypto/sha256-core.S_shipped
> @@ -56,7 +56,6 @@
> #else
> .syntax unified
> # ifdef __thumb2__
> -# define adrl adr
> .thumb
> # else
> .code 32
> @@ -1885,7 +1884,8 @@ sha256_block_data_order_neon:
> stmdb sp!,{r4-r12,lr}
>
> sub r11,sp,#16*4+16
> - adrl r14,K256
> + adr r14,.Lsha256_block_data_order
> + add r14,r14,#K256-.Lsha256_block_data_order
Hi Ard,
Thanks for the patch. With this patch applied:
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- make LLVM=1 LLVM_IAS=1
-j71 defconfig
$ ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- make LLVM=1 LLVM_IAS=1 -j71
...
arch/arm/crypto/sha256-core.S:2038:2: error: out of range immediate fixup value
add r14,r14,#K256-.Lsha256_block_data_order
^
:(
Would the adr_l macro you wrote in
https://lore.kernel.org/linux-arm-kernel/nycvar.YSQ.7.78.906.2009141003360.4095746@xxxxxxxxxxx/T/#t
be helpful here?
> bic r11,r11,#15 @ align for 128-bit stores
> mov r12,sp
> mov sp,r11 @ alloca
> --
> 2.17.1
>
--
Thanks,
~Nick Desaulniers
