riscv: TLS init fix

[Palmer Dabbelt]

On Mon, 19 Feb 2018 18:54:49 PST (-0800), dj@redhat.com wrote:
>
> RISC-V TLS doesn't require GP to be initialized, and doing so breaks
> TLS in a shared object.
>
> diff --git a/sysdeps/riscv/tls-macros.h b/sysdeps/riscv/tls-macros.h
> index 5433ed9d16..7f0dd926d0 100644
> --- a/sysdeps/riscv/tls-macros.h
> +++ b/sysdeps/riscv/tls-macros.h
> @@ -23,19 +23,9 @@
>  #include <sysdep.h>
>  #include "dl-tls.h"
>
> -#define LOAD_GP						\
> -	".option push\n\t"				\
> -	".option norelax\n\t"				\
> -	"la gp, __global_pointer$\n\t"			\
> -	".option pop\n\t"
> -
> -#define UNLOAD_GP
> -
>  #define TLS_GD(x)					\
>  	({ void *__result;				\
> -	asm (LOAD_GP					\
> -	     "la.tls.gd %0, " #x "\n\t"			\
> -	     UNLOAD_GP					\
> +	asm ("la.tls.gd %0, " #x "\n\t"			\
>  	     : "=r" (__result));			\
>  	__tls_get_addr (__result); })
>
> @@ -43,19 +33,15 @@
>
>  #define TLS_IE(x)					\
>  	({ void *__result;				\
> -	asm (LOAD_GP					\
> -	     "la.tls.ie %0, " #x "\n\t"			\
> +	asm ("la.tls.ie %0, " #x "\n\t"			\
>  	     "add %0, %0, tp\n\t"			\
> -	     UNLOAD_GP					\
>  	     : "=r" (__result));			\
>  	__result; })
>
>  #define TLS_LE(x)					\
>  	({ void *__result;				\
> -	asm (LOAD_GP					\
> -	     "lui %0, %%tprel_hi(" #x ")\n\t"		\
> +	asm ("lui %0, %%tprel_hi(" #x ")\n\t"		\
>  	     "add %0, %0, tp, %%tprel_add(" #x ")\n\t"	\
>  	     "addi %0, %0, %%tprel_lo(" #x ")\n\t"	\
> -	     UNLOAD_GP					\
>  	     : "=r" (__result));			\
>  	__result; })

With a ChangeLog and such this looks good to me.  Thanks!