PR tree-optimization/45830
* stmt.c (expand_switch_using_bit_tests_p): New function.
(expand_case): Use it.
* tree.h (expand_switch_using_bit_tests_p): New prototype.
* tree-switch-conversion.c (struct switch_conv_info): Add
bit_test_uniq, bit_test_count and bit_test_bb fields.
(check_range): Fix a comment.
(check_process_case): Compute bit_test_uniq and bit_test_count.
(create_temp_arrays): Use XCNEWVEC, merge 3 arrays into one
allocation.
(free_temp_arrays): Use XDELETEVEC, adjust for the 3 arrays merging.
(constructor_contains_same_values_p): Use FOR_EACH_VEC_ELT.
(array_value_type): New function.
(build_one_array): Use it, if it returned different type,
fold_convert all constructor fields and convert back to the
wider type in the generated code.
(process_switch): Initialize bit_test_uniq, bit_test_count and
bit_test_bb fields. Don't optimize if expand_switch_using_bit_tests_p
returned true.
* gcc.target/i386/pr45830.c: New test.
* gcc.c-torture/execute/pr45830.c: New test.
From-SVN: r166966
