Re: [Valgrind-developers] Valgrind: r15875 - /trunk/coregrind/m_transtab.c

[Yasushi S. <ya...@at...>]

Hi list,

On Fri, 29 Apr 2016 00:52:02 +0900,
svn...@pu... wrote:
> 
> Author: sewardj
> Date: Thu Apr 28 16:52:01 2016
> New Revision: 15875
> 
> Log:
> Un-break ppc32-linux following r15784.  It appears that ppc32-ELF
> layout constraints are different from x86-ELF and so the assertion on
> the sizeof(TTEntryC) fails on ppc32-linux.
> 
> Modified:
>     trunk/coregrind/m_transtab.c
> 
> Modified: trunk/coregrind/m_transtab.c
> ==============================================================================
> --- trunk/coregrind/m_transtab.c (original)
> +++ trunk/coregrind/m_transtab.c Thu Apr 28 16:52:01 2016
> @@ -2448,10 +2448,18 @@
>     if (sizeof(HWord) == 8) {
>        vg_assert(sizeof(TTEntryH) <= 32);
>        vg_assert(sizeof(TTEntryC) <= 112);
> -   } else if (sizeof(HWord) == 4) {
> +   } 
> +   else if (sizeof(HWord) == 4) {
>        vg_assert(sizeof(TTEntryH) <= 20);
> +#     if defined(VGP_ppc32_linux)
> +      /* ppc32-linux is weird.  It thinks alignof(ULong) == 8 and so the
> +         structure is larger than on other 32 bit targets. */

It's also 8 bytes on my armhf debian sid as I checked.

I noticed this when I built trunk r15889 on my 32 ARM board.  When I
run, it failed with:

	./vg-in-place true
	==7907== Memcheck, a memory error detector
	==7907== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
	==7907== Using Valgrind-3.12.0.SVN and LibVEX; rerun with -h for copyright info
	==7907== Command: true
	==7907== 
	
	valgrind: m_transtab.c:2462 (vgPlain_init_tt_tc): Assertion 'sizeof(TTEntryC) <= 88' failed.
	Segmentation fault

Something like this, obviously, works for me.  But, not sure what arch
is weird and what's not; given that ppc, misp, and arm seems to have
the same alignment.

Index: coregrind/m_transtab.c
===================================================================
--- coregrind/m_transtab.c	(revision 15889)
+++ coregrind/m_transtab.c	(working copy)
@@ -2451,7 +2451,7 @@
    } 
    else if (sizeof(HWord) == 4) {
       vg_assert(sizeof(TTEntryH) <= 20);
-#     if defined(VGP_ppc32_linux) || defined(VGP_mips32_linux)
+#     if defined(VGP_ppc32_linux) || defined(VGP_mips32_linux) || defined(VGP_arm_linux)
       /* On PPC32 and MIPS32 platforms alignof(ULong) == 8, so the
          structure is larger than on other 32 bit targets. */
       vg_assert(sizeof(TTEntryC) <= 96);
-- 
           yashi