stmt.c (emit_case_bit_tests): New routine to implement suitable switch statements using the equivalent of "if...
* stmt.c (emit_case_bit_tests): New routine to implement suitable
switch statements using the equivalent of "if ((1<<x) & cst) ... ".
(case_bit_test_cmp): New comparison function for "qsort" to order
case_bit_tests by decreasing number of destination nodes.
(lshift_cheap_p): New function to determine if "1 << x" is cheap.
(expand_end_case_type): Use emit_case_bit_tests to implement
suitable switch statments.
(CASE_USE_BIT_TESTS): New target macro to disable the above.
* Makefile.in (stmt.o): Add dependency on optab.h.
* doc/tm.texi (CASE_USE_BIT_TESTS): Document new target macro.
* gcc.c-torture/execute/switch-1.c: New test case.
From-SVN: r61784
