From: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
To: Richard Henderson <rth@redhat.com>,Sriraman Tallam
<tmsriram@google.com>,GCC Patches
<gcc-patches@gcc.gnu.org>,David Li <davidxl@google.com>,Cary
Coutant <ccoutant@google.com>,Ian Lance Taylor
<iant@google.com>,Paul Pluzhnikov <ppluzhnikov@google.com>
Subject: Re: [PATCH x86_64] Optimize access to globals in "-fpie -pie" builds with copy relocations
Date: Wed, 03 Sep 2014 07:25:00 -0000 [thread overview]
Message-ID: <48b41f33-b2a5-4813-a520-766fdd909bc8@email.android.com> (raw)
In-Reply-To: <54062B52.9040706@redhat.com>
On 2 September 2014 22:40:50 CEST, Richard Henderson <rth@redhat.com> wrote:
>On 06/20/2014 05:17 PM, Sriraman Tallam wrote:
>> Index: config/i386/i386.c
>> ===================================================================
>> --- config/i386/i386.c (revision 211826)
>> +++ config/i386/i386.c (working copy)
>> @@ -12691,7 +12691,9 @@ legitimate_pic_address_disp_p (rtx disp)
>> return true;
>> }
>> else if (!SYMBOL_REF_FAR_ADDR_P (op0)
>> - && SYMBOL_REF_LOCAL_P (op0)
>> + && (SYMBOL_REF_LOCAL_P (op0)
>> + || (TARGET_64BIT && ix86_copyrelocs && flag_pie
>> + && !SYMBOL_REF_FUNCTION_P (op0)))
>> && ix86_cmodel != CM_LARGE_PIC)
>> return true;
>> break;
>
>This is the wrong place to patch.
>
>You ought to be adjusting SYMBOL_REF_LOCAL_P, by providing a modified
>TARGET_BINDS_LOCAL_P.
>
>Note in particular that I believe that you are doing the wrong thing
>with weak
>and COMMON symbols, in that you probably ought not force a copy reloc
>there.
>
>Note the complexity of default_binds_local_p_1, and the fact that all
>you
>really want to modify is
>
> /* If PIC, then assume that any global name can be overridden by
> symbols resolved from other modules. */
> else if (shlib)
> local_p = false;
>
>near the bottom of that function.
Reminds me of PR32219 https://gcc.gnu.org/ml/gcc-patches/2010-03/msg00665.html
but admittedly that is not PIE imposed but still fails on current trunk..
next prev parent reply other threads:[~2014-09-03 7:25 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-15 18:34 Sriraman Tallam
2014-05-19 18:11 ` Sriraman Tallam
2014-06-09 22:55 ` Sriraman Tallam
2014-06-21 0:17 ` Sriraman Tallam
2014-06-26 17:55 ` Sriraman Tallam
2014-07-11 17:42 ` Sriraman Tallam
2014-09-02 18:15 ` Sriraman Tallam
2014-09-02 20:40 ` Richard Henderson
2014-09-03 7:25 ` Bernhard Reutner-Fischer [this message]
2014-09-08 22:19 ` Sriraman Tallam
2014-09-19 21:11 ` Sriraman Tallam
2014-09-29 17:57 ` Sriraman Tallam
2014-10-06 20:43 ` Sriraman Tallam
2014-11-10 23:35 ` Sriraman Tallam
2014-12-02 18:01 ` Sriraman Tallam
2014-12-02 19:06 ` H.J. Lu
2014-12-02 19:19 Uros Bizjak
2014-12-02 19:39 ` H.J. Lu
2014-12-02 19:40 ` H.J. Lu
2014-12-02 20:01 ` Uros Bizjak
2014-12-02 20:43 ` H.J. Lu
2014-12-02 20:19 ` Jakub Jelinek
2014-12-02 22:14 ` H.J. Lu
2014-12-02 23:21 ` H.J. Lu
2014-12-03 13:47 ` H.J. Lu
2014-12-03 15:01 ` H.J. Lu
2014-12-03 21:35 ` H.J. Lu
2014-12-04 12:44 ` Uros Bizjak
2014-12-04 16:46 ` H.J. Lu
2014-12-04 19:32 ` Uros Bizjak
2015-02-03 19:25 ` Sriraman Tallam
2015-02-03 19:26 ` Sriraman Tallam
2015-02-03 19:36 ` Jakub Jelinek
2015-02-03 21:20 ` Sriraman Tallam
2015-02-03 21:29 ` H.J. Lu
2015-02-03 21:36 ` Sriraman Tallam
2015-02-03 22:03 ` H.J. Lu
2015-02-03 22:19 ` Jakub Jelinek
2015-02-04 1:16 ` H.J. Lu
2015-02-04 18:27 ` Sriraman Tallam
2015-02-04 18:31 ` Jakub Jelinek
2015-02-04 18:38 ` H.J. Lu
2015-02-04 18:42 ` Jakub Jelinek
2015-02-04 18:45 ` H.J. Lu
2015-02-04 18:51 ` Sriraman Tallam
2015-02-04 18:57 ` H.J. Lu
2015-02-04 21:53 ` Sriraman Tallam
2015-02-04 22:37 ` H.J. Lu
2015-02-04 22:47 ` Bernhard Reutner-Fischer
2015-02-04 23:10 ` H.J. Lu
2015-02-04 23:29 ` H.J. Lu
2015-02-05 16:57 ` Bernhard Reutner-Fischer
2015-02-05 18:54 ` Richard Henderson
2015-02-05 19:01 ` H.J. Lu
2015-02-05 19:59 ` Richard Henderson
2015-02-05 22:05 ` Sriraman Tallam
2015-02-05 22:47 ` H.J. Lu
2015-02-05 22:48 ` Sriraman Tallam
2015-02-06 16:25 ` H.J. Lu
2015-02-27 23:39 ` H.J. Lu
2015-02-27 23:46 ` H.J. Lu
2014-12-04 22:19 Dominique Dhumieres
2014-12-04 23:54 ` H.J. Lu
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