spirv: Always emit deref_buffer_array_length intrinsics

All the drivers have been converted to setting this option now except
imagination and they don't support SSBOs yet.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3993
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21446>

src/amd/vulkan/radv_shader.c

@@ -762,7 +762,6 @@ radv_shader_spirv_to_nir(struct radv_device *device, const struct radv_pipeline_
          .push_const_addr_format = nir_address_format_logical,
          .shared_addr_format = nir_address_format_32bit_offset,
          .constant_addr_format = nir_address_format_64bit_global,
-         .use_deref_buffer_array_length = true,
          .debug =
             {
                .func = radv_spirv_nir_debug,

src/broadcom/vulkan/v3dv_pipeline.c

@@ -176,7 +176,6 @@ static const struct spirv_to_nir_options default_spirv_options =  {
       .workgroup_memory_explicit_layout = true,
       .image_read_without_format = true,
     },
-   .use_deref_buffer_array_length = true,
    .ubo_addr_format = nir_address_format_32bit_index_offset,
    .ssbo_addr_format = nir_address_format_32bit_index_offset,
    .phys_ssbo_addr_format = nir_address_format_2x32bit_global,

src/compiler/spirv/nir_spirv.h

@@ -65,11 +65,6 @@ struct spirv_to_nir_options {
    /* Create a nir library. */
    bool create_library;
 
-   /* Whether to use nir_intrinsic_deref_buffer_array_length intrinsic instead
-    * of nir_intrinsic_get_ssbo_size to lower OpArrayLength.
-    */
-   bool use_deref_buffer_array_length;
-
    /* Initial value for shader_info::float_controls_execution_mode,
     * indicates hardware requirements rather than shader author intent
     */

src/compiler/spirv/spirv2nir.c

@@ -162,7 +162,6 @@ int main(int argc, char **argv)
 
    struct spirv_to_nir_options spirv_opts = {
       .environment = env,
-      .use_deref_buffer_array_length = env == NIR_SPIRV_OPENGL,
    };
 
    if (shader_stage == MESA_SHADER_KERNEL) {

src/compiler/spirv/vtn_variables.c

@@ -2646,7 +2646,6 @@ vtn_handle_variables(struct vtn_builder *b, SpvOp opcode,
                   "OpArrayLength must reference the last memeber of the "
                   "structure and that must be an array");
 
-      if (b->options->use_deref_buffer_array_length) {
       struct vtn_access_chain chain = {
          .length = 1,
          .link = {
@@ -2661,31 +2660,6 @@ vtn_handle_variables(struct vtn_builder *b, SpvOp opcode,
                                              .access=ptr->access | ptr->type->access);
 
       vtn_push_nir_ssa(b, w[2], array_length);
-      } else {
-         const uint32_t offset = ptr->type->offsets[field];
-         const uint32_t stride = ptr->type->members[field]->stride;
-
-         if (!ptr->block_index) {
-            struct vtn_access_chain chain = {
-               .length = 0,
-            };
-            ptr = vtn_pointer_dereference(b, ptr, &chain);
-            vtn_assert(ptr->block_index);
-         }
-
-         nir_ssa_def *buf_size = nir_get_ssbo_size(&b->nb, ptr->block_index,
-                                                   .access=ptr->access | ptr->type->access);
-
-         /* array_length = max(buffer_size - offset, 0) / stride */
-         nir_ssa_def *array_length =
-            nir_udiv_imm(&b->nb,
-                         nir_usub_sat(&b->nb,
-                                      buf_size,
-                                      nir_imm_int(&b->nb, offset)),
-                         stride);
-
-         vtn_push_nir_ssa(b, w[2], array_length);
-      }
       break;
    }
 

src/freedreno/vulkan/tu_shader.c

@@ -26,7 +26,6 @@ tu_spirv_to_nir(struct tu_device *dev,
 {
    /* TODO these are made-up */
    const struct spirv_to_nir_options spirv_options = {
-      .use_deref_buffer_array_length = true,
       .ubo_addr_format = nir_address_format_vec2_index_32bit_offset,
       .ssbo_addr_format = nir_address_format_vec2_index_32bit_offset,
 

src/gallium/frontends/lavapipe/lvp_pipeline.c

@@ -408,7 +408,6 @@ lvp_shader_compile_to_ir(struct lvp_pipeline *pipeline,
          .float16 = true,
          .demote_to_helper_invocation = true,
       },
-      .use_deref_buffer_array_length = true,
       .ubo_addr_format = nir_address_format_32bit_index_offset,
       .ssbo_addr_format = nir_address_format_32bit_index_offset,
       .phys_ssbo_addr_format = nir_address_format_64bit_global,

src/intel/vulkan/anv_pipeline.c

@@ -208,7 +208,6 @@ anv_shader_stage_to_nir(struct anv_device *device,
          .workgroup_memory_explicit_layout = true,
          .fragment_shading_rate = pdevice->info.ver >= 11,
       },
-      .use_deref_buffer_array_length = true,
       .ubo_addr_format =
          anv_nir_ubo_addr_format(pdevice, device->vk.enabled_features.robustBufferAccess),
       .ssbo_addr_format =

src/intel/vulkan_hasvk/anv_pipeline.c

@@ -114,7 +114,6 @@ anv_shader_stage_to_nir(struct anv_device *device,
          .vk_memory_model_device_scope = true,
          .workgroup_memory_explicit_layout = true,
       },
-      .use_deref_buffer_array_length = true,
       .ubo_addr_format =
          anv_nir_ubo_addr_format(pdevice, device->vk.enabled_features.robustBufferAccess),
       .ssbo_addr_format =

src/mesa/main/glspirv.c

@@ -243,7 +243,6 @@ _mesa_spirv_to_nir(struct gl_context *ctx,
 
    const struct spirv_to_nir_options spirv_options = {
       .environment = NIR_SPIRV_OPENGL,
-      .use_deref_buffer_array_length = true,
       .subgroup_size = SUBGROUP_SIZE_UNIFORM,
       .caps = ctx->Const.SpirVCapabilities,
       .ubo_addr_format = nir_address_format_32bit_index_offset,

src/microsoft/spirv_to_dxil/dxil_spirv_nir.c

@@ -53,13 +53,6 @@ spirv_to_nir_options = {
    .ssbo_addr_format = nir_address_format_32bit_index_offset,
    .shared_addr_format = nir_address_format_32bit_offset,
 
-   /* use_deref_buffer_array_length + nir_lower_explicit_io force
-      * get_ssbo_size to take in the return from load_vulkan_descriptor
-      * instead of vulkan_resource_index. This makes it much easier to
-      * get the DXIL handle for the SSBO.
-      */
-   .use_deref_buffer_array_length = true,
-
    .min_ubo_alignment = 256, /* D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT */
    .min_ssbo_alignment = 16, /* D3D12_RAW_UAV_SRV_BYTE_ALIGNMENT */
 };

src/panfrost/vulkan/panvk_vX_shader.c

@@ -241,7 +241,6 @@ panvk_per_arch(shader_create)(struct panvk_device *dev,
       .caps = {
          .variable_pointers = true,
       },
-      .use_deref_buffer_array_length = true,
       .ubo_addr_format = nir_address_format_32bit_index_offset,
       .ssbo_addr_format = dev->vk.enabled_features.robustBufferAccess ?
                           nir_address_format_64bit_bounded_global :