[Mesa-dev] [PATCH 1/2] tgsi/lowering: add support to lower FLR

[Rob Clark]

On Wed, Apr 13, 2016 at 4:50 PM, Christian Gmeiner
<christian.gmeiner at gmail.com> wrote:
> Signed-off-by: Christian Gmeiner <christian.gmeiner at gmail.com>

btw, Russell sent me a patchset a while back which included FLR/CEIL
and some others.. and also properly fixed up LIT in case of lowering
FLR.. so I think his patchset was more complete.  Perhaps he could
resend to mesa-dev?

BR,
-R

> ---
>  src/gallium/auxiliary/tgsi/tgsi_lowering.c | 54 ++++++++++++++++++++++++++++++
>  src/gallium/auxiliary/tgsi/tgsi_lowering.h |  1 +
>  2 files changed, 55 insertions(+)
>
> diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.c b/src/gallium/auxiliary/tgsi/tgsi_lowering.c
> index a3b90bd..cd5bdc2 100644
> --- a/src/gallium/auxiliary/tgsi/tgsi_lowering.c
> +++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.c
> @@ -258,6 +258,50 @@ transform_dst(struct tgsi_transform_context *tctx,
>     }
>  }
>
> +/* FLR - Floor
> + *
> + *   dst.x = \lfloor src.x\rfloor
> + *   dst.y = \lfloor src.y\rfloor
> + *   dst.z = \lfloor src.z\rfloor
> + *   dst.w = \lfloor src.w\rfloor
> + *
> + * ; needs: 1 tmp
> + * FRC tmpA, src
> + * SUB dst, src, tmpA
> + */
> +#define FLR_GROW (NINST(1) + NINST(2) - OINST(1))
> +#define FLR_TMP  1
> +static void
> +transform_flr(struct tgsi_transform_context *tctx,
> +              struct tgsi_full_instruction *inst)
> +{
> +    struct tgsi_lowering_context *ctx = tgsi_lowering_context(tctx);
> +    struct tgsi_full_dst_register *dst = &inst->Dst[0];
> +    struct tgsi_full_src_register *src = &inst->Src[0];
> +    struct tgsi_full_instruction new_inst;
> +
> +    if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) {
> +       /* FRC tmpA, src */
> +       new_inst = tgsi_default_full_instruction();
> +       new_inst.Instruction.Opcode = TGSI_OPCODE_FRC;
> +       new_inst.Instruction.NumDstRegs = 1;
> +       reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XYZW);
> +       new_inst.Instruction.NumSrcRegs = 1;
> +       reg_src(&new_inst.Src[0], src, SWIZ(X, Y, Z, W));
> +       tctx->emit_instruction(tctx, &new_inst);
> +
> +       /* SUB dst, src, tmpA */
> +       new_inst = tgsi_default_full_instruction();
> +       new_inst.Instruction.Opcode = TGSI_OPCODE_SUB;
> +       new_inst.Instruction.NumDstRegs = 1;
> +       reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZW);
> +       new_inst.Instruction.NumSrcRegs = 2;
> +       reg_src(&new_inst.Src[0], src, SWIZ(X, Y, Z, W));
> +       reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(X, Y, Z, W));
> +       tctx->emit_instruction(tctx, &new_inst);
> +    }
> +}
> +
>  /* XPD - Cross Product
>   *   dst.x = src0.y \times src1.z - src1.y \times src0.z
>   *   dst.y = src0.z \times src1.x - src1.z \times src0.x
> @@ -1336,6 +1380,11 @@ transform_instr(struct tgsi_transform_context *tctx,
>           goto skip;
>        transform_dst(tctx, inst);
>        break;
> +   case TGSI_OPCODE_FLR:
> +       if (!ctx->config->lower_FLR)
> +           goto skip;
> +       transform_flr(tctx, inst);
> +       break;
>     case TGSI_OPCODE_XPD:
>        if (!ctx->config->lower_XPD)
>           goto skip;
> @@ -1460,6 +1509,7 @@ tgsi_transform_lowering(const struct tgsi_lowering_config *config,
>  #define OPCS(x) ((config->lower_ ## x) ? info->opcode_count[TGSI_OPCODE_ ## x] : 0)
>     /* if there are no instructions to lower, then we are done: */
>     if (!(OPCS(DST) ||
> +         OPCS(FLR) ||
>           OPCS(XPD) ||
>           OPCS(SCS) ||
>           OPCS(LRP) ||
> @@ -1489,6 +1539,10 @@ tgsi_transform_lowering(const struct tgsi_lowering_config *config,
>        newlen += DST_GROW * OPCS(DST);
>        numtmp = MAX2(numtmp, DST_TMP);
>     }
> +   if (OPCS(FLR)) {
> +      newlen += FLR_GROW * OPCS(FLR);
> +      numtmp = MAX2(numtmp, FLR_TMP);
> +   }
>     if (OPCS(XPD)) {
>        newlen += XPD_GROW * OPCS(XPD);
>        numtmp = MAX2(numtmp, XPD_TMP);
> diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.h b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
> index 52c204f..803f84e 100644
> --- a/src/gallium/auxiliary/tgsi/tgsi_lowering.h
> +++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
> @@ -55,6 +55,7 @@ struct tgsi_lowering_config
>      * enable lowering of TGSI_OPCODE_<opc>
>      */
>     unsigned lower_DST:1;
> +   unsigned lower_FLR:1;
>     unsigned lower_XPD:1;
>     unsigned lower_SCS:1;
>     unsigned lower_LRP:1;
> --
> 2.5.5
>