[Mesa-dev] [PATCH 10/26] i965: Add tessellation shader VUE map code.
Kenneth Graunke
kenneth at whitecape.org
Wed Dec 2 16:15:51 PST 2015
Based on a patch by Chris Forbes, but largely rewritten by Ken.
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
src/mesa/drivers/dri/i965/brw_compiler.h | 20 ++++++-
src/mesa/drivers/dri/i965/brw_vue_map.c | 98 ++++++++++++++++++++++++++++++--
2 files changed, 111 insertions(+), 7 deletions(-)
Note that VARYING_SLOT_TESS_MAX > BRW_VARYING_SLOT_COUNT.
There's a little bit of funkiness here: i965 extends the VARYING_SLOT_*
enums with a few extra ones for Gen4-5. Tessellation also extends them,
but those values are only used on Gen7+.
So it works. It's just a little...interesting.
diff --git a/src/mesa/drivers/dri/i965/brw_compiler.h b/src/mesa/drivers/dri/i965/brw_compiler.h
index b2251bf..7ad2644 100644
--- a/src/mesa/drivers/dri/i965/brw_compiler.h
+++ b/src/mesa/drivers/dri/i965/brw_compiler.h
@@ -441,7 +441,7 @@ struct brw_vue_map {
* additional processing is applied before storing them in the VUE), the
* value is -1.
*/
- signed char varying_to_slot[BRW_VARYING_SLOT_COUNT];
+ signed char varying_to_slot[VARYING_SLOT_TESS_MAX];
/**
* Map from VUE slot to gl_varying_slot value. For slots that do not
@@ -450,12 +450,24 @@ struct brw_vue_map {
*
* For slots that are not in use, the value is BRW_VARYING_SLOT_PAD.
*/
- signed char slot_to_varying[BRW_VARYING_SLOT_COUNT];
+ signed char slot_to_varying[VARYING_SLOT_TESS_MAX];
/**
* Total number of VUE slots in use
*/
int num_slots;
+
+ /**
+ * Number of per-patch VUE slots. Only valid for tessellation control
+ * shader outputs and tessellation evaluation shader inputs.
+ */
+ int num_per_patch_slots;
+
+ /**
+ * Number of per-vertex VUE slots. Only valid for tessellation control
+ * shader outputs and tessellation evaluation shader inputs.
+ */
+ int num_per_vertex_slots;
};
void brw_print_vue_map(FILE *fp, const struct brw_vue_map *vue_map);
@@ -483,6 +495,10 @@ void brw_compute_vue_map(const struct brw_device_info *devinfo,
GLbitfield64 slots_valid,
bool separate_shader);
+void brw_compute_tess_vue_map(struct brw_vue_map *const vue_map,
+ const GLbitfield64 slots_valid,
+ const GLbitfield is_patch);
+
enum shader_dispatch_mode {
DISPATCH_MODE_4X1_SINGLE = 0,
DISPATCH_MODE_4X2_DUAL_INSTANCE = 1,
diff --git a/src/mesa/drivers/dri/i965/brw_vue_map.c b/src/mesa/drivers/dri/i965/brw_vue_map.c
index 6cb3da4..469538b 100644
--- a/src/mesa/drivers/dri/i965/brw_vue_map.c
+++ b/src/mesa/drivers/dri/i965/brw_vue_map.c
@@ -176,6 +176,77 @@ brw_compute_vue_map(const struct brw_device_info *devinfo,
}
vue_map->num_slots = separate ? slot + 1 : slot;
+ vue_map->num_per_vertex_slots = 0;
+ vue_map->num_per_patch_slots = 0;
+}
+
+/**
+ * Compute the VUE map for tessellation control shader outputs and
+ * tessellation evaluation shader inputs.
+ */
+void
+brw_compute_tess_vue_map(struct brw_vue_map *vue_map,
+ GLbitfield64 vertex_slots,
+ GLbitfield patch_slots)
+{
+ /* I don't think anything actually uses this... */
+ vue_map->slots_valid = vertex_slots;
+
+ vertex_slots &= ~(VARYING_BIT_TESS_LEVEL_OUTER |
+ VARYING_BIT_TESS_LEVEL_INNER);
+
+ /* Make sure that the values we store in vue_map->varying_to_slot and
+ * vue_map->slot_to_varying won't overflow the signed chars that are used
+ * to store them. Note that since vue_map->slot_to_varying sometimes holds
+ * values equal to VARYING_SLOT_TESS_MAX , we need to ensure that
+ * VARYNIG_SLOT_TESS_MAX is <= 127, not 128.
+ */
+ STATIC_ASSERT(VARYING_SLOT_TESS_MAX <= 127);
+
+ for (int i = 0; i < VARYING_SLOT_TESS_MAX ; ++i) {
+ vue_map->varying_to_slot[i] = -1;
+ vue_map->slot_to_varying[i] = BRW_VARYING_SLOT_PAD;
+ }
+
+ int slot = 0;
+
+ /* The first 8 DWords are reserved for the "Patch Header".
+ *
+ * VARYING_SLOT_TESS_LEVEL_OUTER / INNER live here, but the exact layout
+ * depends on the domain type. They might not be in slots 0 and 1 as
+ * described here, but pretending they're separate allows us to uniquely
+ * identify them by distinct slot locations.
+ */
+ assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_INNER, slot++);
+ assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_OUTER, slot++);
+
+ /* XXX: SSO! :( What if you mix and match TCS/TES separate shaders, and
+ * the number of per-patch varyings changes?
+ */
+
+ /* first assign per-patch varyings */
+ while (patch_slots != 0) {
+ const int varying = ffsll(patch_slots) - 1;
+ if (vue_map->varying_to_slot[varying + VARYING_SLOT_PATCH0] == -1) {
+ assign_vue_slot(vue_map, varying + VARYING_SLOT_PATCH0, slot++);
+ }
+ patch_slots &= ~BITFIELD64_BIT(varying);
+ }
+
+ /* apparently, including the patch header... */
+ vue_map->num_per_patch_slots = slot;
+
+ /* then assign per-vertex varyings for each vertex in our patch */
+ while (vertex_slots != 0) {
+ const int varying = ffsll(vertex_slots) - 1;
+ if (vue_map->varying_to_slot[varying] == -1) {
+ assign_vue_slot(vue_map, varying, slot++);
+ }
+ vertex_slots &= ~BITFIELD64_BIT(varying);
+ }
+
+ vue_map->num_per_vertex_slots = slot - vue_map->num_per_patch_slots;
+ vue_map->num_slots = slot;
}
static const char *
@@ -196,11 +267,28 @@ varying_name(brw_varying_slot slot)
void
brw_print_vue_map(FILE *fp, const struct brw_vue_map *vue_map)
{
- fprintf(fp, "VUE map (%d slots, %s)\n",
- vue_map->num_slots, vue_map->separate ? "SSO" : "non-SSO");
- for (int i = 0; i < vue_map->num_slots; i++) {
- fprintf(fp, " [%d] %s\n", i,
- varying_name(vue_map->slot_to_varying[i]));
+ if (vue_map->num_per_vertex_slots > 0 || vue_map->num_per_patch_slots > 0) {
+ fprintf(fp, "PUE map (%d slots, %d/patch, %d/vertex, %s)\n",
+ vue_map->num_slots,
+ vue_map->num_per_patch_slots,
+ vue_map->num_per_vertex_slots,
+ vue_map->separate ? "SSO" : "non-SSO");
+ for (int i = 0; i < vue_map->num_slots; i++) {
+ if (vue_map->slot_to_varying[i] >= VARYING_SLOT_PATCH0) {
+ fprintf(fp, " [%d] VARYING_SLOT_PATCH%d\n", i,
+ vue_map->slot_to_varying[i] - VARYING_SLOT_PATCH0);
+ } else {
+ fprintf(fp, " [%d] %s\n", i,
+ varying_name(vue_map->slot_to_varying[i]));
+ }
+ }
+ } else {
+ fprintf(fp, "VUE map (%d slots, %s)\n",
+ vue_map->num_slots, vue_map->separate ? "SSO" : "non-SSO");
+ for (int i = 0; i < vue_map->num_slots; i++) {
+ fprintf(fp, " [%d] %s\n", i,
+ varying_name(vue_map->slot_to_varying[i]));
+ }
}
fprintf(fp, "\n");
}
--
2.6.2
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