RE: [PATCH][ARM] use vsel instruction for floating point conditional moves in ARMv8

["Kyrylo Tkachov" <kyrylo dot tkachov at arm dot com>]

> -----Original Message-----
> From: Ramana Radhakrishnan
> Sent: 18 February 2013 11:51
> To: Kyrylo Tkachov
> Cc: gcc-patches@gcc.gnu.org; Richard Earnshaw
> Subject: Re: [PATCH][ARM] use vsel instruction for floating point
> conditional moves in ARMv8
> 
> On 01/30/13 09:24, Kyrylo Tkachov wrote:
> > Hi all,
> > This patch uses the new ARMv8 AArch32 vsel instruction to implement
> > conditional moves of floating point numbers.
> > For example, an instruction of the form:
> > 	vsel<cond>.f32  s0, s1, s2
> > means
> > 	s0 := cond ? s1 : s2
> >
> > This can be useful, among other places, in Thumb2 because it doesn't
> require
> > an enclosing IT block.
> > A small catch: The condition code used in vsel can only be one of
> {GE, GT,
> > EQ, VS}. If we want to use their negations {LT, LE, NE, VC} we just
> flip the
> > source operands.
> > A new predicate is introduced that checks that the comparison yields
> an ARM
> > condition code in the set {GE, GT, EQ, VS, LT, LE, NE, VC}.
> >
> > New compilation tests are added. They pass on a model and no new
> regressions
> > on arm-none-eabi with qemu.
> 
> >
> > Ok for trunk?
> 
> Ok for stage1 4.9.

Hi Ramana,

Thanks for the review.
Re-tested on arm-none-eabi against current trunk and applied as r197052.

> 
> Ramana

Thanks,
Kyrill
> 
> >
> > Thanks,
> > Kyrill
> >
> > gcc/ChangeLog
> >
> > 2013-01-30  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
> >
> > 	* config/arm/arm.md (f_sels, f_seld): New types.
> > 	(*cmov<mode>): New pattern.
> > 	* config/arm/predicates.md (arm_vsel_comparison_operator): New
> > predicate.
> >
> >
> > gcc/testsuite/ChangeLog
> >
> > 2013-01-30  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
> >
> > 	* gcc.target/arm/vseleqdf.c: New test.
> > 	* gcc.target/arm/vseleqsf.c: Likewise.
> > 	* gcc.target/arm/vselgedf.c: Likewise.
> > 	* gcc.target/arm/vselgesf.c: Likewise.
> > 	* gcc.target/arm/vselgtdf.c: Likewise.
> > 	* gcc.target/arm/vselgtsf.c: Likewise.
> > 	* gcc.target/arm/vselledf.c: Likewise.
> > 	* gcc.target/arm/vsellesf.c: Likewise.
> > 	* gcc.target/arm/vselltdf.c: Likewise.
> > 	* gcc.target/arm/vselltsf.c: Likewise.
> > 	* gcc.target/arm/vselnedf.c: Likewise.
> > 	* gcc.target/arm/vselnesf.c: Likewise.
> > 	* gcc.target/arm/vselvcdf.c: Likewise.
> > 	* gcc.target/arm/vselvcsf.c: Likewise.
> > 	* gcc.target/arm/vselvsdf.c: Likewise.
> > 	* gcc.target/arm/vselvssf.c: Likewise.
> >