[Mesa-dev] [PATCH 08/11] squash-fwd i965/cs: Add CS push constant structure

[Jordan Justen]

We need information about push constants in two state atoms, so we
calculated roughly the same information twice.

When we add support for uploading both a common (cross-thread) set of
push constants, combined with the previous per-thread push constant
data, things are going to get even more complicated. Therefore, move
these calculations into a separate function that stores the results
into a structure.

Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
---
 src/mesa/drivers/dri/i965/gen7_cs_state.c | 67 +++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/gen7_cs_state.c b/src/mesa/drivers/dri/i965/gen7_cs_state.c
index 7f484dd..04aad13 100644
--- a/src/mesa/drivers/dri/i965/gen7_cs_state.c
+++ b/src/mesa/drivers/dri/i965/gen7_cs_state.c
@@ -44,6 +44,73 @@ get_cs_thread_count(const struct brw_cs_prog_data *cs_prog_data)
 }
 
 
+struct push_const_block {
+   unsigned dwords;     /* Dword count, not reg aligned */
+   unsigned regs;
+   unsigned size;       /* Bytes, register aligned */
+};
+
+
+static void
+fill_push_const_block_info(struct push_const_block *block, unsigned dwords)
+{
+   block->dwords = dwords;
+   block->regs = DIV_ROUND_UP(dwords, 8);
+   block->size = block->regs * 32;
+}
+
+
+struct push_const_info {
+   struct push_const_block cross_thread;
+   struct push_const_block per_thread;
+   struct push_const_block total;
+   bool fill_thread_id;
+};
+
+
+static void
+fill_push_const_info(const struct brw_context *brw,
+                     const struct gl_program *prog,
+                     const struct brw_cs_prog_data *cs_prog_data,
+                     struct push_const_info *info)
+{
+   const struct brw_stage_prog_data *prog_data =
+      (struct brw_stage_prog_data*) cs_prog_data;
+   bool fill_thread_id =
+      cs_prog_data->thread_local_id_index >= 0 &&
+      cs_prog_data->thread_local_id_index < prog_data->nr_params;
+   bool cross_thread_supported = brw->gen > 7 || brw->is_haswell;
+
+   /* The thread ID should be stored in the last param dword */
+   assert(prog_data->nr_params > 0 || !fill_thread_id);
+   assert(!fill_thread_id ||
+          cs_prog_data->thread_local_id_index == prog_data->nr_params - 1);
+
+   unsigned cross_thread_dwords, per_thread_dwords;
+   if (cross_thread_supported && fill_thread_id) {
+      /* Fill all but the last register with cross-thread payload */
+      cross_thread_dwords = 8 * (cs_prog_data->thread_local_id_index / 8);
+      per_thread_dwords = prog_data->nr_params - cross_thread_dwords;
+      assert(per_thread_dwords > 0 && per_thread_dwords <= 8);
+   } else if (cross_thread_supported && !fill_thread_id) {
+      /* Fill all data using cross-thread payload */
+      cross_thread_dwords = prog_data->nr_params;
+      per_thread_dwords = 0u;
+   } else {
+      cross_thread_dwords = 0u;
+      per_thread_dwords = prog_data->nr_params;
+   }
+
+   fill_push_const_block_info(&info->cross_thread, cross_thread_dwords);
+   fill_push_const_block_info(&info->per_thread, per_thread_dwords);
+
+   unsigned threads = get_cs_thread_count(cs_prog_data);
+   unsigned total_dwords =
+      (info->per_thread.size * threads + info->cross_thread.size) / 4;
+   fill_push_const_block_info(&info->total, total_dwords);
+}
+
+
 static void
 brw_upload_cs_state(struct brw_context *brw)
 {
-- 
2.8.1