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[Bug target/24465] [4.1 Regression] -mminimal-toc miscompilation of __thread vars



------- Comment #2 from amodra at bigpond dot net dot au  2005-10-21 05:05 -------
Actually, it's not that RS6000_PIC_OFFSET_TABLE_REGNUM isn't being set up, it's
that RS6000_PIC_OFFSET_TABLE_REGNUM is wrongly being using for tls accesses. 
As currently implemented by gcc, powerpc tls uses x@got@tlsgd and similar.  ie.
we are expecting the linker to manage allocation of tls entries in the got
rather than having gcc allocate them itself in toc sections.  This means that
powerpc64 should use r2 for tls always, even when -mminimal-toc.

Testing the following fix.

Index: gcc/config/rs6000/rs6000.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/rs6000/rs6000.c,v
retrieving revision 1.872
diff -u -p -r1.872 rs6000.c
--- gcc/config/rs6000/rs6000.c  6 Oct 2005 22:58:59 -0000       1.872
+++ gcc/config/rs6000/rs6000.c  21 Oct 2005 05:02:57 -0000
@@ -2979,7 +2979,7 @@ rs6000_legitimize_tls_address (rtx addr,
       rtx r3, got, tga, tmp1, tmp2, eqv;

       if (TARGET_64BIT)
-       got = gen_rtx_REG (Pmode, TOC_REGISTER);
+       got = gen_rtx_REG (Pmode, 2);
       else
        {
          if (flag_pic == 1)


-- 

amodra at bigpond dot net dot au changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.1.0                       |---


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24465


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