nir: add offset to load_coefficients_agx

for indirect varyings

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28483>

src/asahi/compiler/agx_nir_lower_cull_distance.c

@@ -94,7 +94,7 @@ agx_nir_lower_cull_distance_fs(nir_shader *s, unsigned nr_distances)
        * partial derivatives and the value somewhere.
        */
       nir_def *cf = nir_load_coefficients_agx(
-         b, .component = i & 3,
+         b, nir_imm_int(b, 0), .component = i & 3,
          .io_semantics.location = VARYING_SLOT_CULL_PRIMITIVE + (i / 4),
          .io_semantics.num_slots = nr_distances / 4,
          .interp_mode = INTERP_MODE_NOPERSPECTIVE);

src/asahi/compiler/agx_nir_lower_interpolation.c

@@ -123,7 +123,8 @@ interpolate_channel(nir_builder *b, nir_intrinsic_instr *load, unsigned channel)
    sem.num_slots = 1;
 
    nir_def *coefficients = nir_load_coefficients_agx(
-      b, .component = nir_intrinsic_component(load) + channel,
+      b, nir_imm_int(b, 0),
+      .component = nir_intrinsic_component(load) + channel,
       .interp_mode = interp_mode_for_load(load), .io_semantics = sem);
 
    if (load->intrinsic == nir_intrinsic_load_input) {

src/compiler/nir/nir_intrinsics.py

@@ -1803,7 +1803,7 @@ intrinsic("load_from_texture_handle_agx", [2], 1, [],
 # Load the coefficient register corresponding to a given fragment shader input.
 # Coefficient registers are vec3s that are dotted with <x, y, 1> to interpolate
 # the input, where x and y are relative to the 32x32 supertile.
-intrinsic("load_coefficients_agx",
+intrinsic("load_coefficients_agx", [1],
           bit_sizes = [32],
           dest_comp = 3,
           indices=[COMPONENT, IO_SEMANTICS, INTERP_MODE],

src/compiler/nir/nir_lower_io.c

@@ -2737,6 +2737,7 @@ nir_get_io_offset_src_number(const nir_intrinsic_instr *instr)
    case nir_intrinsic_task_payload_atomic_swap:
    case nir_intrinsic_global_atomic:
    case nir_intrinsic_global_atomic_swap:
+   case nir_intrinsic_load_coefficients_agx:
       return 0;
    case nir_intrinsic_load_ubo:
    case nir_intrinsic_load_ssbo: