llvm/llvm/test/tools/UpdateTestChecks/update_test_checks/if_target.test

## Basic test checking that update_test_checks.py works correctly with %if in RUN line
# RUN: cp -f %S/Inputs/if_target.ll %t.ll && %update_test_checks %t.ll --version 4
# RUN: diff -u %t.ll %S/Inputs/if_target.ll.expected
## Check that running the script again does not change the result:
# RUN: %update_test_checks %t.ll
# RUN: diff -u %t.ll %S/Inputs/if_target.ll.expected