Continue strict-volatile-bitfields fixes

[Bernd Schmidt]

On 02/20/2012 12:14 PM, Richard Guenther wrote:
> On Fri, Feb 17, 2012 at 9:51 PM, Thomas Schwinge
> <thomas@codesourcery.com> wrote:
>> Hi!
>>
>> How do we move this issue forward?
>>
>> On Mon, 23 Jan 2012 15:46:34 +0100, Bernd Schmidt <bernds@codesourcery.com> wrote:
>>> That was committed a while ago. The part in stor-layout.c that stops us
>>> from promoting bitfields to normal fields apparently caused some
>>> testsuite regressions in sh tests, where some optimization dump scans
>>> show that we can't perform the optimizations if there are BIT_FIELD_REFs
>>> rather than a normal member access.
>>>
>>> The testcases use things like
>>>   enum something field:8;
>>> and I think applying strict-volatile-bitfields to enums is probably
>>> meaningless. Should we adjust semantics so that the compiler is free to
>>> optimize enum bitfields? The patch would look something like the below.

> 
> What about BOOLEAN_TYPE bitfields?  Thus, why not explicitely
> spell out && TREE_CODE (type) == INTEGER_TYPE?

That would work for me, if we can all agree that
-fstrict-volatile-bitfields should be restricted to INTEGER_TYPE.


Bernd