Re: [Qemu-devel] [PATCH 03/14] target-ppc: Use float64 arg in helper_compute_fprf()

[David Gibson <david@gibson.dropbear.id.au>]

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On Fri, Jan 06, 2017 at 10:27:46AM +0530, Bharata B Rao wrote:
> On Fri, Jan 06, 2017 at 09:01:17AM +1100, David Gibson wrote:
> > On Thu, Jan 05, 2017 at 04:56:08PM +0530, Nikunj A Dadhania wrote:
> > > From: Bharata B Rao <bharata@linux.vnet.ibm.com>
> > > 
> > > Use float64 argument instead of unit64_t in helper_compute_fprf()
> > > This allows code in helper_compute_fprf() to be reused later to
> > > work with float128 argument too.
> > > 
> > > Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> > > Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
> > 
> > Uh.. how can this possibly be correct, without updating the callers of
> > helper_compute_fprf()?
> 
> It works currently because uint64_t argument that is passed by the
> callers is interpreted as float64 arg (via farg.d).
> 
> Let me see if there is a cleaner way of doing this. Casting the
> callers with right floatXX type seems to be the easiest way.
> The requirement here is to ensure that
> 
> helper_compute_fprf_float16(CPUPPCState *env, float16 arg)
> helper_compute_fprf_float32(CPUPPCState *env, float32 arg)
> helper_compute_fprf_float64(CPUPPCState *env, float64 arg)
> helper_compute_fprf_float128(CPUPPCState *env, float128 arg)
> 
> get autogenerated with right floatXX argument so that it can directly
> be used with required routines (like floatXX_is_any_nan etc) w/o
> needing the CPU_DoubleU or other intermediate forms.

Ok.  I think some of this explanation needs to go into the commit
message.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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