microsoft/spirv_to_dxil: check for variables r/w access

Reviewed-by: Jesse Natalie <jenatali@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14765>

src/microsoft/spirv_to_dxil/spirv_to_dxil.c

@@ -336,6 +336,16 @@ spirv_to_dxil(const uint32_t *words, size_t word_count,
             conf->runtime_data_cbv.register_space,
             conf->runtime_data_cbv.base_shader_register);
 
+   NIR_PASS_V(nir, nir_opt_deref);
+
+   if (conf->read_only_images_as_srvs) {
+      const nir_opt_access_options opt_access_options = {
+         .is_vulkan = true,
+         .infer_non_readable = true,
+      };
+      NIR_PASS_V(nir, nir_opt_access, &opt_access_options);
+   }
+
    NIR_PASS_V(nir, nir_split_per_member_structs);
 
    NIR_PASS_V(nir, nir_remove_dead_variables,

src/microsoft/spirv_to_dxil/spirv_to_dxil.h

@@ -144,6 +144,10 @@ struct dxil_spirv_runtime_conf {
       uint16_t y_mask;
       uint16_t z_mask;
    } yz_flip;
+
+   // The caller supports read-only images to be turned into SRV accesses,
+   // which allows us to run the nir_opt_access() pass
+   bool read_only_images_as_srvs;
 };
 
 struct dxil_spirv_debug_options {