* builtins.c (expand_builtin_strcmp): Use const*_rtx when
expanding strcmp at compile-time. Add another transformation.
(expand_builtin_strncmp): Add more transformations. Call
expand_builtin_memcmp, not expand_builtin_strcmp, under
appropriate conditions if HAVE_cmpstrsi.
testsuite:
gcc.c-torture/execute/string-opt-3.c: Add more strcmp checks.
gcc.c-torture/execute/string-opt-8.c: Add more strncmp checks.
From-SVN: r37963
