Estimated hours taken: 1
Change the bit shift functions to perform checking to avoid
implementation defined behaviour.
library/int.m:
Add checking to `int:<<' and `int:>>'.
Add `int:unchecked_left_shift' and `int:unchecked_right_shift'
which do not perform any checking.
compiler/code_util.m:
Replace `int:<<' and `int:>>' with `int:unchecked_left_shift' and
`int:unchecked_right_shift' in the builtin table.
NEWS:
Mention the changes to int.m.
tests/hard_coded/Mmakefile:
tests/hard_coded/shift_test.m:
tests/hard_coded/shift_test.exp:
Test the shift functions.
