Description of problem:
When running valgrind testsuite on ppc64.  We sometimes see the following error:

test_touch_tm.c:11:23: error: builtin __builtin_tabortdc is only valid in 64-bit mode
    __builtin_tabortdc (0,0,0);
                       ^
test_touch_tm.c:12:24: error: builtin __builtin_tabortdci is only valid in 64-bit mode
    __builtin_tabortdci (0,0,0);
                        ^
make[6]: *** [test_touch_tm-test_touch_tm.o] Error 1
make[5]: *** [check-am] Error 2
make[4]: *** [check-recursive] Error 1
make[3]: *** [check-recursive] Error 1
make[2]: *** [check-recursive] Error 1
make[1]: *** [check] Error 2

It aborts entire testsuite.  Which means no results. :(

Version-Release number of selected component (if applicable):
valgrind-3.10.0-14.el7


Steps to Reproduce:
1. make --quiet regtest


The culprit seems to be test_touch_tm.c testcase.

--- test_touch_tm.c ---
#include <stdio.h>

int main (void) {
#ifdef HAS_ISA_2_07
   /* Just get the compiler to generate each of the TM instructions
    * so we can verify that valgrind recognizes them.
    * For now, only the tbegin instruction does anything in valgrind.
    * The rest are just treated as NOPS.
    */
   __builtin_tabort (0);
   __builtin_tabortdc (0,0,0);
   __builtin_tabortdci (0,0,0);
   __builtin_tabortwc (0,0,0);
   __builtin_tabortwci (0,0,0);
   __builtin_tbegin (0);
   __builtin_tend (0);
   //   __builtin_tcheck (0);  tcheck not recognized by compiler
   __builtin_trechkpt ();  // not recognized by early HW
   __builtin_treclaim (0); // not recognized by early HW
   __builtin_tsr (0);
#endif
   return 0;
}
--- --- ---

# gcc -m64 -mhtm -DHAS_ISA_2_07 -Winline -Wall -O -g -mregnames -lm test_touch_tm.c
# gcc -m32 -mhtm -DHAS_ISA_2_07 -Winline -Wall -O -g -mregnames -lm test_touch_tm.c
test_touch_tm.c: In function ‘main’:
test_touch_tm.c:11:23: error: builtin __builtin_tabortdc is only valid in 64-bit mode
    __builtin_tabortdc (0,0,0);
                       ^
test_touch_tm.c:12:24: error: builtin __builtin_tabortdci is only valid in 64-bit mode
    __builtin_tabortdci (0,0,0);
                        ^

Something like the following seems to fix that:

#ifdef __PPC64__
   __builtin_tabortdc (0,0,0);
   __builtin_tabortdci (0,0,0);
#endif