[Fwd: [Valgrind-developers] assertion failures in PPC64 regression tests on IBM 970]

[Dave N. <dc...@us...>]

I started looking into the reason why I was seeing this assertion 
failure in memcheck/tests:
	badjump
	describe-block
	match-overrun
	supp_unknown
only on the IBM PPC970, but you were not seeing it on your G5.
I discovered that the assertion failure happens because of a call to 
make_elf_coredump.  The value of 'limit coredumpsize' on the 970 just 
happened to be 'unlimited' and 0 on the Power5 machine where these tests 
passs cleanly.  If I run tests on my Power5 machine with 'limit 
coredumpsize unlimited' I get the same assertion errors so presumably 
the problem hasn't been resolved in the SVN trunk.

Can you re-produce this behavior on your PPC machines?

Here is some debugging/grepping information:

! valgrind: m_coredump/coredump-elf.c:267 (fill_prstatus): Assertion
'sizeof(*regs) == sizeof(prs->pr_reg)' failed.

0x7005ef3c is in fill_prstatus (m_coredump/coredump-elf.c:267).
262        prs->pr_pgrp = VG_(getpgrp)();
263        prs->pr_sid = VG_(getpgrp)();
264
265        regs = (struct vki_user_regs_struct *)prs->pr_reg;
266
267        vg_assert(sizeof(*regs) == sizeof(prs->pr_reg));

p sizeof(prs->pr_reg)
$1 = 0x180

If you track this down in the source pr_reg is an array of 48 registers.

# searched .h files for vki_user_regs_struct
./include/vki-ppc64-linux.h:/* Kludge?  I don't know where this came
from or if it is right. */
./include/vki-ppc64-linux.h:#define vki_user_regs_struct vki_pt_regs

# from include/vki-ppc64-linux.h
#define VKI_PPC_REG unsigned long
struct vki_pt_regs {
   VKI_PPC_REG gpr[32];
   VKI_PPC_REG nip;
   VKI_PPC_REG msr;
   VKI_PPC_REG orig_gpr3;      /* Used for restarting system calls */
   VKI_PPC_REG ctr;
   VKI_PPC_REG link;
   VKI_PPC_REG xer;
   VKI_PPC_REG ccr;
   VKI_PPC_REG softe;          /* Soft enabled/disabled */
   VKI_PPC_REG trap;           /* Reason for being here */
   VKI_PPC_REG dar;            /* Fault registers */
   VKI_PPC_REG dsisr;
   VKI_PPC_REG result;         /* Result of a system call */
};

This looks like just 44 registers.