intel/fs: disable coarse pixel shader with interpolater messages at sample

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: mesa-stable
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/9292
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23962>

src/intel/compiler/brw_fs.cpp

@@ -7303,7 +7303,7 @@ brw_nir_move_interpolation_to_top(nir_shader *nir)
 }
 
 static void
-brw_nir_populate_wm_prog_data(const nir_shader *shader,
+brw_nir_populate_wm_prog_data(nir_shader *shader,
                               const struct intel_device_info *devinfo,
                               const struct brw_wm_prog_key *key,
                               struct brw_wm_prog_data *prog_data,
@@ -7412,6 +7412,35 @@ brw_nir_populate_wm_prog_data(const nir_shader *shader,
       prog_data->coarse_pixel_dispatch = BRW_NEVER;
    }
 
+   /* ICL PRMs, Volume 9: Render Engine, Shared Functions Pixel Interpolater,
+    * Message Descriptor :
+    *
+    *    "Message Type. Specifies the type of message being sent when
+    *     pixel-rate evaluation is requested :
+    *
+    *     Format = U2
+    *       0: Per Message Offset (eval_snapped with immediate offset)
+    *       1: Sample Position Offset (eval_sindex)
+    *       2: Centroid Position Offset (eval_centroid)
+    *       3: Per Slot Offset (eval_snapped with register offset)
+    *
+    *     Message Type. Specifies the type of message being sent when
+    *     coarse-rate evaluation is requested :
+    *
+    *     Format = U2
+    *       0: Coarse to Pixel Mapping Message (internal message)
+    *       1: Reserved
+    *       2: Coarse Centroid Position (eval_centroid)
+    *       3: Per Slot Coarse Pixel Offset (eval_snapped with register offset)"
+    *
+    * The Sample Position Offset is marked as reserved for coarse rate
+    * evaluation and leads to hangs if we try to use it. So disable coarse
+    * pixel shading if we have any intrinsic that will result in a pixel
+    * interpolater message at sample.
+    */
+   if (brw_nir_pulls_at_sample(shader))
+      prog_data->coarse_pixel_dispatch = BRW_NEVER;
+
    /* We choose to always enable VMask prior to XeHP, as it would cause
     * us to lose out on the eliminate_find_live_channel() optimization.
     */

src/intel/compiler/brw_nir.c

@@ -2083,3 +2083,23 @@ brw_nir_load_global_const(nir_builder *b, nir_intrinsic_instr *load_uniform,
 
    return sysval;
 }
+
+bool
+brw_nir_pulls_at_sample(nir_shader *shader)
+{
+   nir_foreach_function_impl(impl, shader) {
+      nir_foreach_block(block, impl) {
+         nir_foreach_instr(instr, block) {
+            if (instr->type != nir_instr_type_intrinsic)
+               continue;
+
+            nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+
+            if (intrin->intrinsic == nir_intrinsic_load_barycentric_at_sample)
+               return true;
+         }
+      }
+   }
+
+   return false;
+}

src/intel/compiler/brw_nir.h

@@ -270,6 +270,8 @@ nir_shader *brw_nir_create_passthrough_tcs(void *mem_ctx,
                                            const struct brw_compiler *compiler,
                                            const struct brw_tcs_prog_key *key);
 
+bool brw_nir_pulls_at_sample(nir_shader *shader);
+
 #define BRW_NIR_FRAG_OUTPUT_INDEX_SHIFT 0
 #define BRW_NIR_FRAG_OUTPUT_INDEX_MASK INTEL_MASK(0, 0)
 #define BRW_NIR_FRAG_OUTPUT_LOCATION_SHIFT 1