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Re: [PATCH] powerpc: fix ifunc-sel.h with GCC 6


On 2016-07-21 11:36, Aurelien Jarno wrote:
> On 32-bit PowerPC GCC 6 always saves the PIC register on the stack in
> the prologue and adjust the stack in the epilogue. It is therefore not
> possible anymore to just exit the function in the inline asm code,
> otherwise it corrupts the stack pointer. This causes the following tests
> to fail when using GCC 6:
> 
> FAIL: elf/ifuncmain1
> FAIL: elf/ifuncmain1pic
> FAIL: elf/ifuncmain1picstatic
> FAIL: elf/ifuncmain1pie
> FAIL: elf/ifuncmain1staticpic
> FAIL: elf/ifuncmain1staticpie
> FAIL: elf/ifuncmain1vis
> FAIL: elf/ifuncmain1vispic
> FAIL: elf/ifuncmain1vispie
> FAIL: elf/ifuncmain2pic
> FAIL: elf/ifuncmain2picstatic
> FAIL: elf/ifuncmain3
> FAIL: elf/ifuncmain4picstatic
> FAIL: elf/ifuncmain5
> FAIL: elf/ifuncmain5picstatic
> FAIL: elf/ifuncmain5staticpic
> 
> The solution is to replace the beqlr instructions by a beq to the end
> of the inline asm code. This fixes all the above failures.
> 
> ChangeLog:
> 	* sysdeps/powerpc/ifunc-sel.h (ifunc_sel): Replace beqlr instructions
> 	by beq instructions jumping to the end of the function.
> ---
>  ChangeLog                   | 5 +++++
>  sysdeps/powerpc/ifunc-sel.h | 7 ++++---
>  2 files changed, 9 insertions(+), 3 deletions(-)

I forgot to say that I have tested this patch on ppc, ppc64 and ppc64le.
No regression in the testsuite.

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                 http://www.aurel32.net


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