[PATCHES] R600/SI: New V_FRACT fix, intrinsic for S_FLBIT_I32, and more

[Tom Stellard]

On Thu, Mar 05, 2015 at 10:33:15PM +0100, Marek Olšák wrote:
> From 76f3f6561ec37deff8b74bfd9d70c9ad5d175774 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Marek=20Ol=C5=A1=C3=A1k?= <marek.olsak at amd.com>
> Date: Thu, 5 Mar 2015 19:39:30 +0100
> Subject: [PATCH 1/3] R600/SI: Handle FSUB and FADD in SelectVOP3Mods
> 
> Fract tests need this for proper folding of modifiers.
> ---
>  lib/Target/R600/AMDGPUISelDAGToDAG.cpp | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/lib/Target/R600/AMDGPUISelDAGToDAG.cpp b/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
> index 77fce38..ef440ad 100644
> --- a/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
> +++ b/lib/Target/R600/AMDGPUISelDAGToDAG.cpp
> @@ -1157,9 +1157,20 @@ bool AMDGPUDAGToDAGISel::SelectVOP3Mods(SDValue In, SDValue &Src,
>  
>    Src = In;
>  
> +  // This is silly, but it occurs after the fract-to-floor expansion.
> +  if (Src.getOpcode() == ISD::FADD &&
> +      isa<ConstantFPSDNode>(Src.getOperand(1)) &&
> +      cast<ConstantFPSDNode>(Src.getOperand(1))->isZero())
> +    Src = Src.getOperand(0);
> +

This isn't being folded by the DAGCombiner because UnsafeFPMath is
disabled. I don't think we should be attempting to fold this here.


>    if (Src.getOpcode() == ISD::FNEG) {
>      Mods |= SISrcMods::NEG;
>      Src = Src.getOperand(0);
> +  } else if (Src.getOpcode() == ISD::FSUB &&
> +             isa<ConstantFPSDNode>(Src.getOperand(0)) &&
> +             cast<ConstantFPSDNode>(Src.getOperand(0))->isZero()) {
> +    Mods |= SISrcMods::NEG;
> +    Src = Src.getOperand(1);

Same comment for this too.

-Tom

>    }
>  
>    if (Src.getOpcode() == ISD::FABS) {
> -- 
> 2.1.0
>