re PR tree-optimization/67781 (wrong code generated on big-endian with -O1 -fexpensive-optimizations)

2016-01-08  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR tree-optimization/67781
    * tree-ssa-math-opts.c (find_bswap_or_nop): Zero out bytes in cmpxchg
    and cmpnop in two steps: first the ones not accessed in original
    gimple expression in a endian independent way and then the ones not
    accessed in the final result in an endian-specific way.

    gcc/testsuite/
    PR tree-optimization/67781
    * gcc.c-torture/execute/pr67781.c: New file.

From-SVN: r232154