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

[Matthew Gretton-Dann]

Would it be possible for this patch and the others Kyrylo has recently done 
for the new ARMv8 AArch32 instructions to be backported to 4.8?

In particular I'm refering to:
http://gcc.gnu.org/ml/gcc-patches/2013-03/msg00994.html (trunk r197052)
http://gcc.gnu.org/ml/gcc-patches/2013-03/msg00874.html (trunk r197051)
http://gcc.gnu.org/ml/gcc-patches/2013-03/msg00873.html (trunk r197046)
http://gcc.gnu.org/ml/gcc-patches/2013-03/msg00652.html (trunk r197040 and 
197041)

Thanks,

Matt


On 25/03/13 15:21, Kyrylo Tkachov wrote:
-----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.tkac...@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.tkac...@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.







--
Matthew Gretton-Dann
Toolchain Working Group, Linaro