[Mesa-dev] [PATCH] llvmpipe: fix layer/vp input into fs when not written by prior stages
sroland at vmware.com
sroland at vmware.com
Fri Dec 11 13:31:22 PST 2015
From: Roland Scheidegger <sroland at vmware.com>
ARB_fragment_layer_viewport requires that if a fs reads layer or viewport
index but it wasn't output by gs (or vs with other extensions), then it reads
0. This never worked for llvmpipe, and is surprisingly non-trivial to fix.
The problem is the mechanism to handle non-existing outputs in draw is rather
crude, it will simply redirect them to whatever is at output 0, thus later
stages will just get garbage. So, rather than trying to fix this up (which
looks non-trivial), fix this up in llvmpipe setup by detecting this case there
and output a fixed zero directly.
While here, also optimize the hw vertex layout a bit - previously if the gs
outputted layer (or vp) and the fs read those inputs, we'd add them twice
to the vertex layout, which is unnecessary.
And do some minor cleanup, slots don't require that many bits, there was some
bogus (but harmless) float/int mixup for psize slot too, make the slots all
signed instead of mixed signed/unsigned (they can't actually be 0 when valid,
since position is at 0 always at this point, but avoid confusion as they can
be at slot number 0 at vs output), and make sure they are properly initialized
(layer and vp index slot were not which looked fishy as they might not have
got set back to zero when changing from a gs which outputs them to one which
does not).
This fixes the failures in piglit's arb_fragment_layer_viewport group
(3 each for layer and vp).
v2: switch to all signed instead of all unsigned slots.
---
src/gallium/drivers/llvmpipe/lp_bld_interp.h | 3 +-
src/gallium/drivers/llvmpipe/lp_context.h | 18 ++++--
src/gallium/drivers/llvmpipe/lp_setup.c | 2 +-
src/gallium/drivers/llvmpipe/lp_setup_context.h | 8 +--
src/gallium/drivers/llvmpipe/lp_setup_point.c | 2 +-
src/gallium/drivers/llvmpipe/lp_state_derived.c | 75 ++++++++++++++++++-------
src/gallium/drivers/llvmpipe/lp_state_setup.c | 25 ++++++---
src/gallium/drivers/llvmpipe/lp_state_setup.h | 1 -
8 files changed, 91 insertions(+), 43 deletions(-)
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_interp.h b/src/gallium/drivers/llvmpipe/lp_bld_interp.h
index 9029d2a..0a52642 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_interp.h
+++ b/src/gallium/drivers/llvmpipe/lp_bld_interp.h
@@ -63,7 +63,8 @@ enum lp_interp {
LP_INTERP_LINEAR,
LP_INTERP_PERSPECTIVE,
LP_INTERP_POSITION,
- LP_INTERP_FACING
+ LP_INTERP_FACING,
+ LP_INTERP_ZERO
};
struct lp_shader_input {
diff --git a/src/gallium/drivers/llvmpipe/lp_context.h b/src/gallium/drivers/llvmpipe/lp_context.h
index c9a5d67..70ec032 100644
--- a/src/gallium/drivers/llvmpipe/lp_context.h
+++ b/src/gallium/drivers/llvmpipe/lp_context.h
@@ -108,22 +108,28 @@ struct llvmpipe_context {
struct vertex_info vertex_info;
/** Which vertex shader output slot contains color */
- int color_slot[2];
+ int8_t color_slot[2];
/** Which vertex shader output slot contains bcolor */
- int bcolor_slot[2];
+ int8_t bcolor_slot[2];
/** Which vertex shader output slot contains point size */
- int psize_slot;
+ int8_t psize_slot;
/** Which vertex shader output slot contains viewport index */
- int viewport_index_slot;
+ int8_t viewport_index_slot;
/** Which geometry shader output slot contains layer */
- int layer_slot;
+ int8_t layer_slot;
/** A fake frontface output for unfilled primitives */
- int face_slot;
+ int8_t face_slot;
+
+ /** Which output slot is used for the fake vp index info */
+ int8_t fake_vpindex_slot;
+
+ /** Which output slot is used for the fake layer info */
+ int8_t fake_layer_slot;
/** Depth format and bias settings. */
boolean floating_point_depth;
diff --git a/src/gallium/drivers/llvmpipe/lp_setup.c b/src/gallium/drivers/llvmpipe/lp_setup.c
index 1778b13..ddbb88e 100644
--- a/src/gallium/drivers/llvmpipe/lp_setup.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup.c
@@ -1207,7 +1207,7 @@ lp_setup_update_state( struct lp_setup_context *setup,
/* Will probably need to move this somewhere else, just need
* to know about vertex shader point size attribute.
*/
- setup->psize = lp->psize_slot;
+ setup->psize_slot = lp->psize_slot;
setup->viewport_index_slot = lp->viewport_index_slot;
setup->layer_slot = lp->layer_slot;
setup->face_slot = lp->face_slot;
diff --git a/src/gallium/drivers/llvmpipe/lp_setup_context.h b/src/gallium/drivers/llvmpipe/lp_setup_context.h
index 2410e23..80acd74 100644
--- a/src/gallium/drivers/llvmpipe/lp_setup_context.h
+++ b/src/gallium/drivers/llvmpipe/lp_setup_context.h
@@ -105,10 +105,10 @@ struct lp_setup_context
float pixel_offset;
float line_width;
float point_size;
- float psize;
- unsigned viewport_index_slot;
- unsigned layer_slot;
- int face_slot;
+ int8_t psize_slot;
+ int8_t viewport_index_slot;
+ int8_t layer_slot;
+ int8_t face_slot;
struct pipe_framebuffer_state fb;
struct u_rect framebuffer;
diff --git a/src/gallium/drivers/llvmpipe/lp_setup_point.c b/src/gallium/drivers/llvmpipe/lp_setup_point.c
index 75544b5..14c389f 100644
--- a/src/gallium/drivers/llvmpipe/lp_setup_point.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup_point.c
@@ -328,7 +328,7 @@ try_setup_point( struct lp_setup_context *setup,
struct llvmpipe_context *lp_context = (struct llvmpipe_context *)setup->pipe;
/* x/y positions in fixed point */
const struct lp_setup_variant_key *key = &setup->setup.variant->key;
- const int sizeAttr = setup->psize;
+ const int sizeAttr = setup->psize_slot;
const float size
= (setup->point_size_per_vertex && sizeAttr > 0) ? v0[sizeAttr][0]
: setup->point_size;
diff --git a/src/gallium/drivers/llvmpipe/lp_state_derived.c b/src/gallium/drivers/llvmpipe/lp_state_derived.c
index a25e832..2b4b07c 100644
--- a/src/gallium/drivers/llvmpipe/lp_state_derived.c
+++ b/src/gallium/drivers/llvmpipe/lp_state_derived.c
@@ -55,10 +55,19 @@ compute_vertex_info(struct llvmpipe_context *llvmpipe)
draw_prepare_shader_outputs(llvmpipe->draw);
+ /*
+ * Those can't actually be 0 (because pos is always at 0).
+ * But use ints anyway to avoid confusion (in vs outputs, they
+ * can very well be at pos 0).
+ */
llvmpipe->color_slot[0] = -1;
llvmpipe->color_slot[1] = -1;
llvmpipe->bcolor_slot[0] = -1;
llvmpipe->bcolor_slot[1] = -1;
+ llvmpipe->viewport_index_slot = -1;
+ llvmpipe->layer_slot = -1;
+ llvmpipe->face_slot = -1;
+ llvmpipe->psize_slot = -1;
/*
* Match FS inputs against VS outputs, emitting the necessary
@@ -90,10 +99,34 @@ compute_vertex_info(struct llvmpipe_context *llvmpipe)
}
if (lpfs->info.base.input_semantic_name[i] == TGSI_SEMANTIC_FACE) {
- llvmpipe->face_slot = vinfo->num_attribs;
+ llvmpipe->face_slot = (int)vinfo->num_attribs;
draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
} else if (lpfs->info.base.input_semantic_name[i] == TGSI_SEMANTIC_PRIMID) {
draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
+ /*
+ * For vp index and layer, if the fs requires them but the vs doesn't
+ * provide them, store the slot - we'll later replace the data directly
+ * with zero (as required by ARB_fragment_layer_viewport). This is
+ * because draw itself just redirects them to whatever was at output 0.
+ * We'll also store the real vpindex/layer slot for setup use.
+ */
+ } else if (lpfs->info.base.input_semantic_name[i] ==
+ TGSI_SEMANTIC_VIEWPORT_INDEX) {
+ if (vs_index >= 0) {
+ llvmpipe->viewport_index_slot = (int)vinfo->num_attribs;
+ }
+ else {
+ llvmpipe->fake_vpindex_slot = (int)vinfo->num_attribs;
+ }
+ draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
+ } else if (lpfs->info.base.input_semantic_name[i] == TGSI_SEMANTIC_LAYER) {
+ if (vs_index >= 0) {
+ llvmpipe->layer_slot = (int)vinfo->num_attribs;
+ }
+ else {
+ llvmpipe->fake_layer_slot = (int)vinfo->num_attribs;
+ }
+ draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
} else {
/*
* Emit the requested fs attribute for all but position.
@@ -101,6 +134,7 @@ compute_vertex_info(struct llvmpipe_context *llvmpipe)
draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_PERSPECTIVE, vs_index);
}
}
+
/* Figure out if we need bcolor as well.
*/
for (i = 0; i < 2; i++) {
@@ -113,37 +147,36 @@ compute_vertex_info(struct llvmpipe_context *llvmpipe)
}
}
-
/* Figure out if we need pointsize as well.
*/
vs_index = draw_find_shader_output(llvmpipe->draw,
TGSI_SEMANTIC_PSIZE, 0);
if (vs_index >= 0) {
- llvmpipe->psize_slot = vinfo->num_attribs;
+ llvmpipe->psize_slot = (int)vinfo->num_attribs;
draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
}
- /* Figure out if we need viewport index */
- vs_index = draw_find_shader_output(llvmpipe->draw,
- TGSI_SEMANTIC_VIEWPORT_INDEX,
- 0);
- if (vs_index >= 0) {
- llvmpipe->viewport_index_slot = vinfo->num_attribs;
- draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
- } else {
- llvmpipe->viewport_index_slot = 0;
+ /* Figure out if we need viewport index (if it wasn't already in fs input) */
+ if (llvmpipe->viewport_index_slot < 0) {
+ vs_index = draw_find_shader_output(llvmpipe->draw,
+ TGSI_SEMANTIC_VIEWPORT_INDEX,
+ 0);
+ if (vs_index >= 0) {
+ llvmpipe->viewport_index_slot = (int)vinfo->num_attribs;
+ draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
+ }
}
- /* Figure out if we need layer */
- vs_index = draw_find_shader_output(llvmpipe->draw,
- TGSI_SEMANTIC_LAYER,
- 0);
- if (vs_index >= 0) {
- llvmpipe->layer_slot = vinfo->num_attribs;
- draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
- } else {
- llvmpipe->layer_slot = 0;
+ /* Figure out if we need layer (if it wasn't already in fs input) */
+ if (llvmpipe->layer_slot < 0) {
+ vs_index = draw_find_shader_output(llvmpipe->draw,
+ TGSI_SEMANTIC_LAYER,
+ 0);
+ if (vs_index >= 0) {
+ llvmpipe->layer_slot = (int)vinfo->num_attribs;
+ draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_CONSTANT, vs_index);
+ }
}
draw_compute_vertex_size(vinfo);
diff --git a/src/gallium/drivers/llvmpipe/lp_state_setup.c b/src/gallium/drivers/llvmpipe/lp_state_setup.c
index 64215be..8172a56 100644
--- a/src/gallium/drivers/llvmpipe/lp_state_setup.c
+++ b/src/gallium/drivers/llvmpipe/lp_state_setup.c
@@ -602,6 +602,13 @@ emit_tri_coef( struct gallivm_state *gallivm,
*/
break;
+ case LP_INTERP_ZERO:
+ /*
+ * The information we get from the output is bogus, replace it
+ * with zero.
+ */
+ emit_constant_coef4(gallivm, args, slot+1, args->bld.zero);
+ break;
case LP_INTERP_FACING:
emit_facing_coef(gallivm, args, slot+1);
break;
@@ -848,14 +855,10 @@ lp_make_setup_variant_key(struct llvmpipe_context *lp,
key->size = Offset(struct lp_setup_variant_key,
inputs[key->num_inputs]);
- key->color_slot = lp->color_slot [0];
+ key->color_slot = lp->color_slot[0];
key->bcolor_slot = lp->bcolor_slot[0];
- key->spec_slot = lp->color_slot [1];
- key->bspec_slot = lp->bcolor_slot[1];
- assert(key->color_slot == lp->color_slot [0]);
- assert(key->bcolor_slot == lp->bcolor_slot[0]);
- assert(key->spec_slot == lp->color_slot [1]);
- assert(key->bspec_slot == lp->bcolor_slot[1]);
+ key->spec_slot = lp->color_slot[1];
+ key->bspec_slot = lp->bcolor_slot[1];
/*
* If depth is floating point, depth bias is calculated with respect
@@ -876,7 +879,13 @@ lp_make_setup_variant_key(struct llvmpipe_context *lp,
key->pad = 0;
memcpy(key->inputs, fs->inputs, key->num_inputs * sizeof key->inputs[0]);
for (i = 0; i < key->num_inputs; i++) {
- if (key->inputs[i].interp == LP_INTERP_COLOR) {
+ if (key->inputs[i].interp == LP_INTERP_CONSTANT) {
+ if (key->inputs[i].src_index == lp->fake_vpindex_slot ||
+ key->inputs[i].src_index == lp->fake_layer_slot) {
+ key->inputs[i].interp = LP_INTERP_ZERO;
+ }
+ }
+ else if (key->inputs[i].interp == LP_INTERP_COLOR) {
if (lp->rasterizer->flatshade)
key->inputs[i].interp = LP_INTERP_CONSTANT;
else
diff --git a/src/gallium/drivers/llvmpipe/lp_state_setup.h b/src/gallium/drivers/llvmpipe/lp_state_setup.h
index 82af835..9ad2444 100644
--- a/src/gallium/drivers/llvmpipe/lp_state_setup.h
+++ b/src/gallium/drivers/llvmpipe/lp_state_setup.h
@@ -18,7 +18,6 @@ struct lp_setup_variant_key {
unsigned size:16;
unsigned num_inputs:8;
int color_slot:8;
-
int bcolor_slot:8;
int spec_slot:8;
int bspec_slot:8;
--
2.1.4
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