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From: Florian Weimer <fweimer@redhat.com>
To: Tulio Magno Quites Machado Filho via Libc-alpha
	<libc-alpha@sourceware.org>
Cc: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>,
	amodra@gmail.com
Subject: Re: [PATCH] powerpc64: Implement TLS using PC-relative addressing
Date: Thu, 01 Oct 2020 10:49:43 +0200	[thread overview]
Message-ID: <87y2kqjpp4.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <20200930195512.724059-1-tuliom@linux.ibm.com> (Tulio Magno Quites Machado Filho via Libc-alpha's message of "Wed, 30 Sep 2020 16:55:12 -0300")

* Tulio Magno Quites Machado Filho via Libc-alpha:

> diff --git a/sysdeps/powerpc/mod-tlsopt-powerpc.c b/sysdeps/powerpc/mod-tlsopt-powerpc.c
> index ee0db12a73..5856dab60b 100644
> --- a/sysdeps/powerpc/mod-tlsopt-powerpc.c
> +++ b/sysdeps/powerpc/mod-tlsopt-powerpc.c
> @@ -24,7 +24,14 @@ tls_get_addr_opt_test (void)
>    tls_index *tls_arg;
>  #ifdef __powerpc64__
>    register unsigned long thread_pointer __asm__ ("r13");
> +  /* PC-relative addressing is available when compiling with -mpcrel.
> +     The first releases of GCC 10 do support -mpcrel, but do not export
> +     __PCREL__.  */
> +# if defined(__PCREL__) || __GNUC__ <= 10 && defined(_ARCH_PWR10)
> +  asm ("pla %0,foo@got@tlsgd@pcrel" : "=r" (tls_arg));
> +# else
>    asm ("addi %0,2,foo@got@tlsgd" : "=r" (tls_arg));
> +# endif

Should this check for binutils support for @pcrel?  Or won't GCC enable
_ARCH_PWR10 in this case?

Thanks,
Florian
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  reply	other threads:[~2020-10-01  8:49 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-30 19:55 Tulio Magno Quites Machado Filho
2020-10-01  8:49 ` Florian Weimer [this message]
2020-10-01 11:15   ` Alan Modra
2020-10-01  9:01 ` Andreas Schwab
2021-01-22  1:29   ` [PATCHv2] " Tulio Magno Quites Machado Filho
2021-01-25 15:20     ` Tulio Magno Quites Machado Filho
2021-01-25 17:13     ` Adhemerval Zanella
2021-01-25 20:22       ` Tulio Magno Quites Machado Filho
2021-01-27 11:16         ` Alan Modra

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