[PATCH] ARM: type casts update_sched_clock cyc_to_sched_clock cyc_to_fixed_sched_clock
Russell King - ARM Linux
linux at arm.linux.org.uk
Tue Apr 5 05:01:00 EDT 2011
On Tue, Apr 05, 2011 at 10:31:44AM +0200, Uwe Kleine-König wrote:
> On Tue, Apr 05, 2011 at 08:56:22AM +0100, Russell King - ARM Linux wrote:
> > On Tue, Apr 05, 2011 at 09:43:21AM +0200, Jan Weitzel wrote:
> > > parameter "u32 mask" type cast befor inversion
> > Nak. I want a 32-bit all ones quantity.
> > unsigned long long vali = (unsigned short)~0;
> > unsigned long long vall = ~(unsigned short)0;
> BTW, the definiton of vall is equivalent to
> unsigned long long valu = ~(unsigned int)0;
> because ~ converts the unsigned short to unsigned int.
No. The value gets promoted to int not unsigned int.
> > compiles to:
> > vali:
> > .word 65535
> > .word 0
> > vall:
> > .word -1
> > .word -1
> I really wonder about that. If I take a value of 0xffffffff (i.e. a 32
> bit wide int == ~0U) and assign that to an 64-bit unsigned long long I'd
> expect it to get the value 0x00000000ffffffffULL, not
> 0xffffffffffffffffULL. What's wrong?
See above. int not unsigned int. And it makes a difference:
unsigned long long vals = ~(int)0;
unsigned long long valu = ~(unsigned int)0;
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