[Mesa-dev] [PATCH 3/5] gallium: add opcodes/cap for fine derivative support
Ilia Mirkin
imirkin at alum.mit.edu
Thu Aug 14 09:26:07 PDT 2014
On Thu, Aug 14, 2014 at 12:21 PM, Roland Scheidegger <sroland at vmware.com> wrote:
> Am 14.08.2014 16:39, schrieb Ilia Mirkin:
>> I guess a question is whether we should even bother with the fine
>> version at all then? Just map everything to DDX/DDY... Although I
>> guess if llvmpipe does the coarse version sometimes, at least the fine
>> version is warranted.
> I think it's nice to have both versions. llvmpipe only does the coarse
> version for its internal use.
Yeah, I also just found out that r600 evergreen+ can do either one,
and at present does the coarse one. I'm going to push these out
tonight unless there are further comments. (Pretty sure all the
patches got R-b'd... if not, I'll obviously wait on those)
> If a shader would do a ddx and ddy and then use the values for a texture
> instruction with explicit derivatives, some slower path is used for
> sampling (which can handle different mip levels in a quad) (though this
> is a lot subject currently to debug vars such as no_quad_lod). The
> problem is that even if you'd do a coarse_ddx, we still would fall back
> to that slower path anyway, because (unlike intel hw where it really
> matters if the actual lod values are different) we won't detect that
> there is in fact just one lod per quad, so right now there would not
> really be a benefit. Obviously, if you do the derivatives calculations
> as part of the sampling itself, this is not a problem. FWIW the slow
> path isn't actually all THAT more complicated than the per-quad lod path
> - strides, mip image offsets etc. need to be looked up per pixel rather
> than per quad, plus some slowness comes from the fact that stupid
> sse/avx (only avx2) doesn't have true vector shift... There's also the
> fact that the tex filter may be different too per pixel (with different
> min/mag filter) though since we do (in some cases at least with avx) do
> texture sampling for multiple quads at once this is something which
> needs to be handled in any case. I suspect hw being slower with
> different effective lods per pixel has similar reasons - there's just
> more work to be done.
>
> Roland
>
>
>
>>
>> On Thu, Aug 14, 2014 at 10:12 AM, Roland Scheidegger <sroland at vmware.com> wrote:
>>> Reviewed-by: Roland Scheidegger <sroland at vmware.com>
>>>
>>> llvmpipe also already does the fine version. A coarse version (which we
>>> indeed do when used implicitly for sampling though with some other
>>> changes) might be minimally simpler though not even sure (might save a
>>> shuffle instruction somewhere), but probably not worth it (plus, d3d10
>>> sm4 had deriv_rtx and sm5 deriv_rtx_coarse/deriv_rtx_fine but the sm4
>>> versions correspond to the fine versions so this was required).
>>>
>>> Roland
>>>
>>> Am 14.08.2014 06:52, schrieb Ilia Mirkin:
>>>> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
>>>> ---
>>>> src/gallium/auxiliary/tgsi/tgsi_info.c | 3 +++
>>>> src/gallium/auxiliary/tgsi/tgsi_util.c | 2 ++
>>>> src/gallium/docs/source/screen.rst | 2 ++
>>>> src/gallium/docs/source/tgsi.rst | 12 ++++++++++--
>>>> src/gallium/drivers/freedreno/freedreno_screen.c | 1 +
>>>> src/gallium/drivers/i915/i915_screen.c | 1 +
>>>> src/gallium/drivers/ilo/ilo_screen.c | 1 +
>>>> src/gallium/drivers/llvmpipe/lp_screen.c | 1 +
>>>> src/gallium/drivers/nouveau/nv30/nv30_screen.c | 1 +
>>>> src/gallium/drivers/nouveau/nv50/nv50_screen.c | 1 +
>>>> src/gallium/drivers/nouveau/nvc0/nvc0_screen.c | 1 +
>>>> src/gallium/drivers/r300/r300_screen.c | 1 +
>>>> src/gallium/drivers/r600/r600_pipe.c | 1 +
>>>> src/gallium/drivers/radeonsi/si_pipe.c | 1 +
>>>> src/gallium/drivers/softpipe/sp_screen.c | 1 +
>>>> src/gallium/drivers/svga/svga_screen.c | 1 +
>>>> src/gallium/drivers/vc4/vc4_screen.c | 1 +
>>>> src/gallium/include/pipe/p_defines.h | 1 +
>>>> src/gallium/include/pipe/p_shader_tokens.h | 5 ++++-
>>>> 19 files changed, 35 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/src/gallium/auxiliary/tgsi/tgsi_info.c b/src/gallium/auxiliary/tgsi/tgsi_info.c
>>>> index e24348f..35f9747 100644
>>>> --- a/src/gallium/auxiliary/tgsi/tgsi_info.c
>>>> +++ b/src/gallium/auxiliary/tgsi/tgsi_info.c
>>>> @@ -235,6 +235,9 @@ static const struct tgsi_opcode_info opcode_info[TGSI_OPCODE_LAST] =
>>>> { 1, 1, 0, 0, 0, 0, OTHR, "INTERP_CENTROID", TGSI_OPCODE_INTERP_CENTROID },
>>>> { 1, 2, 0, 0, 0, 0, OTHR, "INTERP_SAMPLE", TGSI_OPCODE_INTERP_SAMPLE },
>>>> { 1, 2, 0, 0, 0, 0, OTHR, "INTERP_OFFSET", TGSI_OPCODE_INTERP_OFFSET },
>>>> +
>>>> + { 1, 1, 0, 0, 0, 0, COMP, "DDX_FINE", TGSI_OPCODE_DDX_FINE },
>>>> + { 1, 1, 0, 0, 0, 0, COMP, "DDY_FINE", TGSI_OPCODE_DDY_FINE },
>>>> };
>>>>
>>>> const struct tgsi_opcode_info *
>>>> diff --git a/src/gallium/auxiliary/tgsi/tgsi_util.c b/src/gallium/auxiliary/tgsi/tgsi_util.c
>>>> index e48159c..e1cba95 100644
>>>> --- a/src/gallium/auxiliary/tgsi/tgsi_util.c
>>>> +++ b/src/gallium/auxiliary/tgsi/tgsi_util.c
>>>> @@ -245,6 +245,8 @@ tgsi_util_get_inst_usage_mask(const struct tgsi_full_instruction *inst,
>>>> case TGSI_OPCODE_USNE:
>>>> case TGSI_OPCODE_IMUL_HI:
>>>> case TGSI_OPCODE_UMUL_HI:
>>>> + case TGSI_OPCODE_DDX_FINE:
>>>> + case TGSI_OPCODE_DDY_FINE:
>>>> /* Channel-wise operations */
>>>> read_mask = write_mask;
>>>> break;
>>>> diff --git a/src/gallium/docs/source/screen.rst b/src/gallium/docs/source/screen.rst
>>>> index 814e3ae..6fecc15 100644
>>>> --- a/src/gallium/docs/source/screen.rst
>>>> +++ b/src/gallium/docs/source/screen.rst
>>>> @@ -213,6 +213,8 @@ The integer capabilities:
>>>> * ``PIPE_CAP_DRAW_INDIRECT``: Whether the driver supports taking draw arguments
>>>> { count, instance_count, start, index_bias } from a PIPE_BUFFER resource.
>>>> See pipe_draw_info.
>>>> +* ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE``: Whether the fragment shader supports
>>>> + the FINE versions of DDX/DDY.
>>>>
>>>>
>>>> .. _pipe_capf:
>>>> diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
>>>> index ac0ea54..7d5918f 100644
>>>> --- a/src/gallium/docs/source/tgsi.rst
>>>> +++ b/src/gallium/docs/source/tgsi.rst
>>>> @@ -433,7 +433,11 @@ This instruction replicates its result.
>>>> dst = \cos{src.x}
>>>>
>>>>
>>>> -.. opcode:: DDX - Derivative Relative To X
>>>> +.. opcode:: DDX, DDX_FINE - Derivative Relative To X
>>>> +
>>>> +The fine variant is only used when ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE`` is
>>>> +advertised. When it is, the fine version guarantees one derivative per row
>>>> +while DDX is allowed to be the same for the entire 2x2 quad.
>>>>
>>>> .. math::
>>>>
>>>> @@ -446,7 +450,11 @@ This instruction replicates its result.
>>>> dst.w = partialx(src.w)
>>>>
>>>>
>>>> -.. opcode:: DDY - Derivative Relative To Y
>>>> +.. opcode:: DDY, DDY_FINE - Derivative Relative To Y
>>>> +
>>>> +The fine variant is only used when ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE`` is
>>>> +advertised. When it is, the fine version guarantees one derivative per column
>>>> +while DDY is allowed to be the same for the entire 2x2 quad.
>>>>
>>>> .. math::
>>>>
>>>> diff --git a/src/gallium/drivers/freedreno/freedreno_screen.c b/src/gallium/drivers/freedreno/freedreno_screen.c
>>>> index de69b14..b156d8b 100644
>>>> --- a/src/gallium/drivers/freedreno/freedreno_screen.c
>>>> +++ b/src/gallium/drivers/freedreno/freedreno_screen.c
>>>> @@ -216,6 +216,7 @@ fd_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> /* Stream output. */
>>>> diff --git a/src/gallium/drivers/i915/i915_screen.c b/src/gallium/drivers/i915/i915_screen.c
>>>> index ca3dd4a..53d5e75 100644
>>>> --- a/src/gallium/drivers/i915/i915_screen.c
>>>> +++ b/src/gallium/drivers/i915/i915_screen.c
>>>> @@ -231,6 +231,7 @@ i915_get_param(struct pipe_screen *screen, enum pipe_cap cap)
>>>> case PIPE_CAP_TGSI_VS_LAYER_VIEWPORT:
>>>> case PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> case PIPE_CAP_MIN_MAP_BUFFER_ALIGNMENT:
>>>> diff --git a/src/gallium/drivers/ilo/ilo_screen.c b/src/gallium/drivers/ilo/ilo_screen.c
>>>> index bd6d8dd..991d2d0 100644
>>>> --- a/src/gallium/drivers/ilo/ilo_screen.c
>>>> +++ b/src/gallium/drivers/ilo/ilo_screen.c
>>>> @@ -433,6 +433,7 @@ ilo_get_param(struct pipe_screen *screen, enum pipe_cap param)
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> case PIPE_CAP_MAX_VERTEX_STREAMS:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> default:
>>>> diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
>>>> index 347b1af..f4f3257 100644
>>>> --- a/src/gallium/drivers/llvmpipe/lp_screen.c
>>>> +++ b/src/gallium/drivers/llvmpipe/lp_screen.c
>>>> @@ -248,6 +248,7 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
>>>> case PIPE_CAP_SAMPLE_SHADING:
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> case PIPE_CAP_FAKE_SW_MSAA:
>>>> return 1;
>>>> diff --git a/src/gallium/drivers/nouveau/nv30/nv30_screen.c b/src/gallium/drivers/nouveau/nv30/nv30_screen.c
>>>> index 2860188..4766955 100644
>>>> --- a/src/gallium/drivers/nouveau/nv30/nv30_screen.c
>>>> +++ b/src/gallium/drivers/nouveau/nv30/nv30_screen.c
>>>> @@ -148,6 +148,7 @@ nv30_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_USER_VERTEX_BUFFERS:
>>>> case PIPE_CAP_COMPUTE:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/src/gallium/drivers/nouveau/nv50/nv50_screen.c b/src/gallium/drivers/nouveau/nv50/nv50_screen.c
>>>> index 7b1b112..34cca3d 100644
>>>> --- a/src/gallium/drivers/nouveau/nv50/nv50_screen.c
>>>> +++ b/src/gallium/drivers/nouveau/nv50/nv50_screen.c
>>>> @@ -200,6 +200,7 @@ nv50_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> case PIPE_CAP_COMPUTE:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
>>>> index d372a0f..17aee63 100644
>>>> --- a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
>>>> +++ b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
>>>> @@ -184,6 +184,7 @@ nvc0_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_TGSI_VS_LAYER_VIEWPORT:
>>>> case PIPE_CAP_FAKE_SW_MSAA:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> }
>>>>
>>>> diff --git a/src/gallium/drivers/r300/r300_screen.c b/src/gallium/drivers/r300/r300_screen.c
>>>> index 4e46f77..ad599e9 100644
>>>> --- a/src/gallium/drivers/r300/r300_screen.c
>>>> +++ b/src/gallium/drivers/r300/r300_screen.c
>>>> @@ -178,6 +178,7 @@ static int r300_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> /* SWTCL-only features. */
>>>> diff --git a/src/gallium/drivers/r600/r600_pipe.c b/src/gallium/drivers/r600/r600_pipe.c
>>>> index 20d9f95..8a5ba79 100644
>>>> --- a/src/gallium/drivers/r600/r600_pipe.c
>>>> +++ b/src/gallium/drivers/r600/r600_pipe.c
>>>> @@ -319,6 +319,7 @@ static int r600_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_SAMPLE_SHADING:
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> /* Stream output. */
>>>> diff --git a/src/gallium/drivers/radeonsi/si_pipe.c b/src/gallium/drivers/radeonsi/si_pipe.c
>>>> index 879387f..0f10f3b 100644
>>>> --- a/src/gallium/drivers/radeonsi/si_pipe.c
>>>> +++ b/src/gallium/drivers/radeonsi/si_pipe.c
>>>> @@ -254,6 +254,7 @@ static int si_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_FAKE_SW_MSAA:
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> case PIPE_CAP_TEXTURE_BORDER_COLOR_QUIRK:
>>>> diff --git a/src/gallium/drivers/softpipe/sp_screen.c b/src/gallium/drivers/softpipe/sp_screen.c
>>>> index 7be39d4..5e2640d 100644
>>>> --- a/src/gallium/drivers/softpipe/sp_screen.c
>>>> +++ b/src/gallium/drivers/softpipe/sp_screen.c
>>>> @@ -194,6 +194,7 @@ softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
>>>> case PIPE_CAP_SAMPLE_SHADING:
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> case PIPE_CAP_FAKE_SW_MSAA:
>>>> return 1;
>>>> diff --git a/src/gallium/drivers/svga/svga_screen.c b/src/gallium/drivers/svga/svga_screen.c
>>>> index 2fcc75c..d140f56 100644
>>>> --- a/src/gallium/drivers/svga/svga_screen.c
>>>> +++ b/src/gallium/drivers/svga/svga_screen.c
>>>> @@ -278,6 +278,7 @@ svga_get_param(struct pipe_screen *screen, enum pipe_cap param)
>>>> case PIPE_CAP_TEXTURE_GATHER_OFFSETS:
>>>> case PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>> case PIPE_CAP_MIN_MAP_BUFFER_ALIGNMENT:
>>>> return 64;
>>>> diff --git a/src/gallium/drivers/vc4/vc4_screen.c b/src/gallium/drivers/vc4/vc4_screen.c
>>>> index c044c8e..7e59613 100644
>>>> --- a/src/gallium/drivers/vc4/vc4_screen.c
>>>> +++ b/src/gallium/drivers/vc4/vc4_screen.c
>>>> @@ -157,6 +157,7 @@ vc4_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
>>>> case PIPE_CAP_MAX_TEXEL_OFFSET:
>>>> case PIPE_CAP_MAX_VERTEX_STREAMS:
>>>> case PIPE_CAP_DRAW_INDIRECT:
>>>> + case PIPE_CAP_TGSI_FS_FINE_DERIVATIVE:
>>>> return 0;
>>>>
>>>> /* Stream output. */
>>>> diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
>>>> index 7a10d98..53d5d4b 100644
>>>> --- a/src/gallium/include/pipe/p_defines.h
>>>> +++ b/src/gallium/include/pipe/p_defines.h
>>>> @@ -562,6 +562,7 @@ enum pipe_cap {
>>>> PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION = 99,
>>>> PIPE_CAP_MAX_VERTEX_STREAMS = 100,
>>>> PIPE_CAP_DRAW_INDIRECT = 101,
>>>> + PIPE_CAP_TGSI_FS_FINE_DERIVATIVE = 102,
>>>> };
>>>>
>>>> #define PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_NV50 (1 << 0)
>>>> diff --git a/src/gallium/include/pipe/p_shader_tokens.h b/src/gallium/include/pipe/p_shader_tokens.h
>>>> index 0d3ad6a..2921f81 100644
>>>> --- a/src/gallium/include/pipe/p_shader_tokens.h
>>>> +++ b/src/gallium/include/pipe/p_shader_tokens.h
>>>> @@ -481,7 +481,10 @@ struct tgsi_property_data {
>>>> #define TGSI_OPCODE_INTERP_SAMPLE 193
>>>> #define TGSI_OPCODE_INTERP_OFFSET 194
>>>>
>>>> -#define TGSI_OPCODE_LAST 195
>>>> +#define TGSI_OPCODE_DDX_FINE 195
>>>> +#define TGSI_OPCODE_DDY_FINE 196
>>>> +
>>>> +#define TGSI_OPCODE_LAST 197
>>>>
>>>> #define TGSI_SAT_NONE 0 /* do not saturate */
>>>> #define TGSI_SAT_ZERO_ONE 1 /* clamp to [0,1] */
>>>>
>>>
>
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