[google] Backport r171347 and r181549 from trunk (strict volatile bitfield) (issue5434084)

[Jakub Jelinek]

On Tue, Nov 29, 2011 at 05:59:53PM -0800, Doug Kwan wrote:
>     This is a backport for two upstream patches into our 4.6 branch.
> I submitted the first patch by Julian a while ago for backport but
> Richard Earnshaw pointed out a problem with the first patch.  The second
> patch from Joey fixes that problem.  This was tested on x86 and ARM.

Why hasn't this been proposed for upstream 4.6 instead?
See PR51442.

> 2011-11-22   Doug Kwan  <dougkwan@google.com>
> 
> 	Backport r171347 and r181549 from trunk.
> 
> 	gcc/
> 	2011-03-23  Julian Brown  <julian@codesourcery.com>
> 
> 		* expr.c (expand_expr_real_1): Only use BLKmode for volatile
> 		accesses which are not naturally aligned.
> 	
> 	2011-11-20  Joey Ye  <joey.ye@arm.com>
> 
>         	* expr.c (expand_expr_real_1): Correctly handle strict volatile
>         	bitfield loads smaller than mode size.
> 
> 	gcc/testsuite/
> 	2011-11-20  Joey Ye  <joey.ye@arm.com>
> 
>         	* gcc.dg/volatile-bitfields-1.c: New.

	Jakub