spirv: Use the same types for resource indices as pointers

We need more space than just a 32-bit scalar and we have to burn all
that space anyway so we may as well expose it to the driver.  This also
fixes a subtle bug when UBOs and SSBOs have different pointer types.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>

src/compiler/nir/nir_intrinsics.py

@@ -158,7 +158,7 @@ intrinsic("interp_deref_at_offset", src_comp=[1, 2], dest_comp=0,
 
 # Ask the driver for the size of a given buffer. It takes the buffer index
 # as source.
-intrinsic("get_buffer_size", src_comp=[1], dest_comp=1,
+intrinsic("get_buffer_size", src_comp=[-1], dest_comp=1,
           flags=[CAN_ELIMINATE, CAN_REORDER])
 
 # a barrier is an intrinsic with no inputs/outputs but which can't be moved
@@ -363,12 +363,12 @@ image("store_raw_intel", src_comp=[1, 0])
 # (the result of a vulkan_resource_index or vulkan_resource_reindex) which
 # corresponds to the tuple (set, binding, index) and computes an index
 # corresponding to tuple (set, binding, idx + src1).
-intrinsic("vulkan_resource_index", src_comp=[1], dest_comp=1,
+intrinsic("vulkan_resource_index", src_comp=[1], dest_comp=0,
           indices=[DESC_SET, BINDING, DESC_TYPE],
           flags=[CAN_ELIMINATE, CAN_REORDER])
-intrinsic("vulkan_resource_reindex", src_comp=[1, 1], dest_comp=1,
+intrinsic("vulkan_resource_reindex", src_comp=[0, 1], dest_comp=0,
           indices=[DESC_TYPE], flags=[CAN_ELIMINATE, CAN_REORDER])
-intrinsic("load_vulkan_descriptor", src_comp=[1], dest_comp=0,
+intrinsic("load_vulkan_descriptor", src_comp=[-1], dest_comp=0,
           indices=[DESC_TYPE], flags=[CAN_ELIMINATE, CAN_REORDER])
 
 # variable atomic intrinsics

src/compiler/spirv/vtn_variables.c

@@ -98,6 +98,19 @@ vk_desc_type_for_mode(struct vtn_builder *b, enum vtn_variable_mode mode)
    }
 }
 
+static const struct glsl_type *
+vtn_ptr_type_for_mode(struct vtn_builder *b, enum vtn_variable_mode mode)
+{
+   switch (mode) {
+   case vtn_variable_mode_ubo:
+      return b->options->ubo_ptr_type;
+   case vtn_variable_mode_ssbo:
+      return b->options->ssbo_ptr_type;
+   default:
+      vtn_fail("Invalid mode for vulkan_resource_index");
+   }
+}
+
 static nir_ssa_def *
 vtn_variable_resource_index(struct vtn_builder *b, struct vtn_variable *var,
                             nir_ssa_def *desc_array_index)
@@ -115,7 +128,13 @@ vtn_variable_resource_index(struct vtn_builder *b, struct vtn_variable *var,
    nir_intrinsic_set_binding(instr, var->binding);
    nir_intrinsic_set_desc_type(instr, vk_desc_type_for_mode(b, var->mode));
 
-   nir_ssa_dest_init(&instr->instr, &instr->dest, 1, 32, NULL);
+   const struct glsl_type *index_type =
+      b->options->lower_ubo_ssbo_access_to_offsets ?
+      glsl_uint_type() : vtn_ptr_type_for_mode(b, var->mode);
+
+   instr->num_components = glsl_get_vector_elements(index_type);
+   nir_ssa_dest_init(&instr->instr, &instr->dest, instr->num_components,
+                     glsl_get_bit_size(index_type), NULL);
    nir_builder_instr_insert(&b->nb, &instr->instr);
 
    return &instr->dest.ssa;
@@ -132,7 +151,13 @@ vtn_resource_reindex(struct vtn_builder *b, enum vtn_variable_mode mode,
    instr->src[1] = nir_src_for_ssa(offset_index);
    nir_intrinsic_set_desc_type(instr, vk_desc_type_for_mode(b, mode));
 
-   nir_ssa_dest_init(&instr->instr, &instr->dest, 1, 32, NULL);
+   const struct glsl_type *index_type =
+      b->options->lower_ubo_ssbo_access_to_offsets ?
+      glsl_uint_type() : vtn_ptr_type_for_mode(b, mode);
+
+   instr->num_components = glsl_get_vector_elements(index_type);
+   nir_ssa_dest_init(&instr->instr, &instr->dest, instr->num_components,
+                     glsl_get_bit_size(index_type), NULL);
    nir_builder_instr_insert(&b->nb, &instr->instr);
 
    return &instr->dest.ssa;
@@ -140,17 +165,20 @@ vtn_resource_reindex(struct vtn_builder *b, enum vtn_variable_mode mode,
 
 static nir_ssa_def *
 vtn_descriptor_load(struct vtn_builder *b, enum vtn_variable_mode mode,
-                    const struct glsl_type *desc_type, nir_ssa_def *desc_index)
+                    nir_ssa_def *desc_index)
 {
    nir_intrinsic_instr *desc_load =
       nir_intrinsic_instr_create(b->nb.shader,
                                  nir_intrinsic_load_vulkan_descriptor);
    desc_load->src[0] = nir_src_for_ssa(desc_index);
-   desc_load->num_components = glsl_get_vector_elements(desc_type);
    nir_intrinsic_set_desc_type(desc_load, vk_desc_type_for_mode(b, mode));
+
+   const struct glsl_type *ptr_type = vtn_ptr_type_for_mode(b, mode);
+
+   desc_load->num_components = glsl_get_vector_elements(ptr_type);
    nir_ssa_dest_init(&desc_load->instr, &desc_load->dest,
                      desc_load->num_components,
-                     glsl_get_bit_size(desc_type), NULL);
+                     glsl_get_bit_size(ptr_type), NULL);
    nir_builder_instr_insert(&b->nb, &desc_load->instr);
 
    return &desc_load->dest.ssa;
@@ -254,8 +282,7 @@ vtn_nir_deref_pointer_dereference(struct vtn_builder *b,
        * final block index.  Insert a descriptor load and cast to a deref to
        * start the deref chain.
        */
-      nir_ssa_def *desc =
-         vtn_descriptor_load(b, base->mode, base->ptr_type->type, block_index);
+      nir_ssa_def *desc = vtn_descriptor_load(b, base->mode, block_index);
 
       assert(base->mode == vtn_variable_mode_ssbo ||
              base->mode == vtn_variable_mode_ubo);
@@ -1765,10 +1792,6 @@ vtn_pointer_to_ssa(struct vtn_builder *b, struct vtn_pointer *ptr)
       if (vtn_pointer_is_external_block(b, ptr) &&
           vtn_type_contains_block(b, ptr->type) &&
           ptr->mode != vtn_variable_mode_phys_ssbo) {
-         const unsigned bit_size = glsl_get_bit_size(ptr->ptr_type->type);
-         const unsigned num_components =
-            glsl_get_vector_elements(ptr->ptr_type->type);
-
          /* In this case, we're looking for a block index and not an actual
           * deref.
           *
@@ -1793,13 +1816,7 @@ vtn_pointer_to_ssa(struct vtn_builder *b, struct vtn_pointer *ptr)
             ptr = vtn_nir_deref_pointer_dereference(b, ptr, &chain);
          }
 
-         /* A block index is just a 32-bit value but the pointer has some
-          * other dimensionality.  Cram it in there and we'll unpack it later
-          * in vtn_pointer_from_ssa.
-          */
-         const unsigned swiz[4] = { 0, };
-         return nir_swizzle(&b->nb, nir_u2u(&b->nb, ptr->block_index, bit_size),
-                            swiz, num_components, false);
+         return ptr->block_index;
       } else {
          return &vtn_pointer_to_deref(b, ptr)->dest.ssa;
       }
@@ -1859,11 +1876,10 @@ vtn_pointer_from_ssa(struct vtn_builder *b, nir_ssa_def *ssa,
       } else if (vtn_type_contains_block(b, ptr->type) &&
                  ptr->mode != vtn_variable_mode_phys_ssbo) {
          /* This is a pointer to somewhere in an array of blocks, not a
-          * pointer to somewhere inside the block.  We squashed it into a
-          * random vector type before so just pick off the first channel and
-          * cast it back to 32 bits.
+          * pointer to somewhere inside the block.  Set the block index
+          * instead of making a cast.
           */
-         ptr->block_index = nir_u2u32(&b->nb, nir_channel(&b->nb, ssa, 0));
+         ptr->block_index = ssa;
       } else {
          /* This is a pointer to something internal or a pointer inside a
           * block.  It's just a regular cast.

src/intel/compiler/brw_fs_nir.cpp

@@ -4368,6 +4368,7 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
       break;
 
    case nir_intrinsic_get_buffer_size: {
+      assert(nir_src_num_components(instr->src[0]) == 1);
       unsigned ssbo_index = nir_src_is_const(instr->src[0]) ?
                             nir_src_as_uint(instr->src[0]) : 0;
 

src/intel/compiler/brw_vec4_nir.cpp

@@ -467,6 +467,7 @@ vec4_visitor::nir_emit_intrinsic(nir_intrinsic_instr *instr)
    }
 
    case nir_intrinsic_get_buffer_size: {
+      assert(nir_src_num_components(instr->src[0]) == 1);
       unsigned ssbo_index = nir_src_is_const(instr->src[0]) ?
                             nir_src_as_uint(instr->src[0]) : 0;
 

src/intel/vulkan/anv_nir_apply_pipeline_layout.c

@@ -158,10 +158,13 @@ lower_res_index_intrinsic(nir_intrinsic_instr *intrin,
    if (nir_src_is_const(intrin->src[0]) || state->add_bounds_checks)
       array_index = nir_umin(b, array_index, nir_imm_int(b, array_size - 1));
 
-   nir_ssa_def *block_index = nir_iadd_imm(b, array_index, surface_index);
+   /* We're using nir_address_format_vk_index_offset */
+   nir_ssa_def *index =
+      nir_vec2(b, nir_iadd_imm(b, array_index, surface_index),
+                  nir_imm_int(b, 0));
 
    assert(intrin->dest.is_ssa);
-   nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(block_index));
+   nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(index));
    nir_instr_remove(&intrin->instr);
 }
 
@@ -178,8 +181,12 @@ lower_res_reindex_intrinsic(nir_intrinsic_instr *intrin,
     * add of the two indices.
     */
    assert(intrin->src[0].is_ssa && intrin->src[1].is_ssa);
-   nir_ssa_def *new_index = nir_iadd(b, intrin->src[0].ssa,
-                                        intrin->src[1].ssa);
+   nir_ssa_def *old_index = intrin->src[0].ssa;
+   nir_ssa_def *offset = intrin->src[1].ssa;
+
+   nir_ssa_def *new_index =
+      nir_vec2(b, nir_iadd(b, nir_channel(b, old_index, 0), offset),
+                  nir_channel(b, old_index, 1));
 
    assert(intrin->dest.is_ssa);
    nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(new_index));
@@ -196,13 +203,32 @@ lower_load_vulkan_descriptor(nir_intrinsic_instr *intrin,
 
    /* We follow the nir_address_format_vk_index_offset model */
    assert(intrin->src[0].is_ssa);
-   nir_ssa_def *vec2 = nir_vec2(b, intrin->src[0].ssa, nir_imm_int(b, 0));
+   nir_ssa_def *index = intrin->src[0].ssa;
 
    assert(intrin->dest.is_ssa);
-   nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(vec2));
+   nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(index));
    nir_instr_remove(&intrin->instr);
 }
 
+static void
+lower_get_buffer_size(nir_intrinsic_instr *intrin,
+                      struct apply_pipeline_layout_state *state)
+{
+   nir_builder *b = &state->builder;
+
+   b->cursor = nir_before_instr(&intrin->instr);
+
+   assert(intrin->src[0].is_ssa);
+   nir_ssa_def *index = intrin->src[0].ssa;
+
+   /* We're following the nir_address_format_vk_index_offset model so the
+    * binding table index is the first component of the address.  The
+    * back-end wants a scalar binding table index source.
+    */
+   nir_instr_rewrite_src(&intrin->instr, &intrin->src[0],
+                         nir_src_for_ssa(nir_channel(b, index, 0)));
+}
+
 static void
 lower_image_intrinsic(nir_intrinsic_instr *intrin,
                       struct apply_pipeline_layout_state *state)
@@ -402,6 +428,9 @@ apply_pipeline_layout_block(nir_block *block,
          case nir_intrinsic_load_vulkan_descriptor:
             lower_load_vulkan_descriptor(intrin, state);
             break;
+         case nir_intrinsic_get_buffer_size:
+            lower_get_buffer_size(intrin, state);
+            break;
          case nir_intrinsic_image_deref_load:
          case nir_intrinsic_image_deref_store:
          case nir_intrinsic_image_deref_atomic_add: