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cpuuse, rtmonuse and gcc
- Date: Fri, 28 Mar 2008 09:17:21 -0500
- From: joel.sherrill at OARcorp.com (Joel Sherrill)
- Subject: cpuuse, rtmonuse and gcc
Aleix Conchillo Flaqu? wrote:
> I am using REMS 4.6.6 with the PR#1237 patch.
Then you have a version using floating point. Check out
the code on the CVS head. It is using integer math only.
If you don't want to do the backport, email me privately and
we can discuss arranging me to do it for you. It is what
keeps my kids fed.
> On Fri, Mar 28, 2008 at 2:58 PM, Joel Sherrill
> <joel.sherrill at oarcorp.com> wrote:
>> Jiri Gaisler wrote:
>> > This is pretty bad. If the kernel uses floats, then compilation
>> > with -msoft-float will not work if the application later is linked
>> > without -msoft-float. Are the CPU_usage_Dump() and Period_usage_Dump()
>> > new functions or have they always been around?
>> I think our emails crossed. Older versions had floating
>> point math if the FPU defined was set to TRUE.
>> Newer versions have been rewritten to completely
>> use integer math.
>> So the question for Aleix is what version of RTEMS
>> do you have? If it is the older FP using version,
>> can you backport the integer version of the functions
>> and post a patch.
>>> Are there other
>> > functions in the kernel that uses floats as well?
>> There are not supposed to be. But gcc has surprised
>> us in the past by generating FP using code when you
>> least expected it.
>> So AFAIK "float/double" C types should not be found
>> anywhere in the code except to declare the FP context
>> structures anymore.
Joel Sherrill, Ph.D. Director of Research & Development
joel.sherrill at OARcorp.com On-Line Applications Research
Ask me about RTEMS: a free RTOS Huntsville AL 35805
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