freedreno/ir3: Handle cases where we decide not to lower UBO 0 loads.

We advertize 4096 vec4s of GL uniform storage, but the HW can only store
512 vec4s in the const buffer.

Closes: #3049
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5273>

diff --git a/src/freedreno/ir3/ir3_nir_analyze_ubo_ranges.c b/src/freedreno/ir3/ir3_nir_analyze_ubo_ranges.c
index d7dd9b912c8de7ba2012b71b87247d45fc059194..449d908a290d2d9548c8916d30093c8af57283c6 100644 (file)
--- a/src/freedreno/ir3/ir3_nir_analyze_ubo_ranges.c
+++ b/src/freedreno/ir3/ir3_nir_analyze_ubo_ranges.c
@@ -27,16 +27,29 @@
 #include "compiler/nir/nir_builder.h"
 #include "util/u_math.h"
 
+static bool
+range_is_gl_uniforms(struct ir3_ubo_range *r)
+{
+       return !r->bindless && r->block == 0;
+}
+
 static inline struct ir3_ubo_range
-get_ubo_load_range(nir_intrinsic_instr *instr, uint32_t alignment)
+get_ubo_load_range(nir_shader *nir, nir_intrinsic_instr *instr, uint32_t alignment)
 {
        struct ir3_ubo_range r;
 
-       int offset = nir_src_as_uint(instr->src[1]);
-       const int bytes = nir_intrinsic_dest_components(instr) * 4;
+       if (nir_src_is_const(instr->src[1])) {
+               int offset = nir_src_as_uint(instr->src[1]);
+               const int bytes = nir_intrinsic_dest_components(instr) * 4;
 
-       r.start = ROUND_DOWN_TO(offset, alignment * 16);
-       r.end = ALIGN(offset + bytes, alignment * 16);
+               r.start = ROUND_DOWN_TO(offset, alignment * 16);
+               r.end = ALIGN(offset + bytes, alignment * 16);
+       } else {
+               /* The other valid place to call this is on the GL default uniform block */
+               assert(nir_src_as_uint(instr->src[0]) == 0);
+               r.start = 0;
+               r.end = ALIGN(nir->num_uniforms * 16, alignment * 16);
+       }
 
        return r;
 }
@@ -87,30 +100,21 @@ static void
 gather_ubo_ranges(nir_shader *nir, nir_intrinsic_instr *instr,
                                  struct ir3_ubo_analysis_state *state, uint32_t alignment)
 {
-       struct ir3_ubo_range *old_r = get_existing_range(instr, state, true);
-       if (!old_r)
+       if (ir3_shader_debug & IR3_DBG_NOUBOOPT)
                return;
 
-       if (!nir_src_is_const(instr->src[1])) {
-               if (!old_r->bindless && old_r->block == 0) {
-                       /* If this is an indirect on UBO 0, we'll still lower it back to
-                        * load_uniform.  Set the range to cover all of UBO 0.
-                        */
-                       old_r->start = 0;
-                       old_r->end = ALIGN(nir->num_uniforms * 16, alignment * 16);
-               }
-
+       struct ir3_ubo_range *old_r = get_existing_range(instr, state, true);
+       if (!old_r)
                return;
-       }
 
-       const struct ir3_ubo_range r = get_ubo_load_range(instr, alignment);
-
-       /* if UBO lowering is disabled, we still want to lower block 0
-        * (which is normal uniforms):
+       /* We don't know how to get the size of UBOs being indirected on, other
+        * than on the GL uniforms where we have some other shader_info data.
         */
-       if ((old_r->bindless || old_r->block != 0) && (ir3_shader_debug & IR3_DBG_NOUBOOPT))
+       if (!nir_src_is_const(instr->src[1]) && !range_is_gl_uniforms(old_r))
                return;
 
+       const struct ir3_ubo_range r = get_ubo_load_range(nir, instr, alignment);
+
        if (r.start < old_r->start)
                old_r->start = r.start;
        if (old_r->end < r.end)
@@ -212,24 +216,20 @@ lower_ubo_load_to_uniform(nir_intrinsic_instr *instr, nir_builder *b,
                return;
        }
 
-       if (range->bindless || range->block > 0) {
-               /* We don't lower dynamic array indexing either, but we definitely should.
-                * We don't have a good way of determining the range of the dynamic
-                * access, so for now just fall back to pulling.
-                */
-               if (!nir_src_is_const(instr->src[1])) {
-                       track_ubo_use(instr, b, num_ubos);
-                       return;
-               }
+       /* We don't have a good way of determining the range of the dynamic
+        * access in general, so for now just fall back to pulling.
+        */
+       if (!nir_src_is_const(instr->src[1]) && !range_is_gl_uniforms(range))
+               return;
 
-               /* After gathering the UBO access ranges, we limit the total
-                * upload. Reject if we're now outside the range.
-                */
-               const struct ir3_ubo_range r = get_ubo_load_range(instr, alignment);
-               if (!(range->start <= r.start && r.end <= range->end)) {
-                       track_ubo_use(instr, b, num_ubos);
-                       return;
-               }
+       /* After gathering the UBO access ranges, we limit the total
+        * upload. Don't lower if this load is outside the range.
+        */
+       const struct ir3_ubo_range r = get_ubo_load_range(b->shader,
+                       instr, alignment);
+       if (!(range->start <= r.start && r.end <= range->end)) {
+               track_ubo_use(instr, b, num_ubos);
+               return;
        }
 
        nir_ssa_def *ubo_offset = nir_ssa_for_src(b, instr->src[1], 1);