intel/compiler: Fix sparse cube map array coordinate lowering

Brown paper bag fix for my untested review feedback comments.

Cube array images use a coordinate of the form <X, Y, 6*Slice+Face>,
while cube array textures use a <X, Y, Slice, Face> style coordinate.

This code tried to convert one to the other, but instead of writing
Z / 6 and Z % 6, we tried to reuse our original division result.  What
we wanted was Z - (Z/6) * 6, but instead we botched it and wrote Z-Z*6
which produced...totally invalid cube faces.

Fixes: fe81d40bff26 ("intel/nir: add lower for sparse images & textures")
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24481>

diff --git a/src/intel/compiler/brw_nir_lower_sparse.c b/src/intel/compiler/brw_nir_lower_sparse.c
index 8976762..9b74b51 100644 (file)
--- a/src/intel/compiler/brw_nir_lower_sparse.c
+++ b/src/intel/compiler/brw_nir_lower_sparse.c
@@ -138,7 +138,7 @@ lower_sparse_image_load(nir_builder *b, nir_intrinsic_instr *intrin)
       nir_ssa_def *img_layer = nir_channel(b, intrin->src[1].ssa, 2);
       nir_ssa_def *tex_slice = nir_idiv(b, img_layer, nir_imm_int(b, 6));
       nir_ssa_def *tex_face =
-         nir_iadd(b, img_layer, nir_ineg(b, nir_imul_imm(b, img_layer, 6)));
+         nir_iadd(b, img_layer, nir_ineg(b, nir_imul_imm(b, tex_slice, 6)));
       nir_ssa_def *comps[4] = {
          nir_channel(b, intrin->src[1].ssa, 0),
          nir_channel(b, intrin->src[1].ssa, 1),