nir/lower_io: Add a build_addr_for_var helper
[mesa.git] / src / compiler / nir / nir_lower_io.c
index b3595bb19d53da32f014b2c6cb9f3ff18c2ae7b1..22f9d667328551d8f1e6dcde9dd33a7892a0271c 100644 (file)
 #include "nir_builder.h"
 #include "nir_deref.h"
 
+#include "util/u_math.h"
+
 struct lower_io_state {
    void *dead_ctx;
    nir_builder builder;
-   int (*type_size)(const struct glsl_type *type);
+   int (*type_size)(const struct glsl_type *type, bool);
    nir_variable_mode modes;
    nir_lower_io_options options;
 };
 
+static nir_intrinsic_op
+ssbo_atomic_for_deref(nir_intrinsic_op deref_op)
+{
+   switch (deref_op) {
+#define OP(O) case nir_intrinsic_deref_##O: return nir_intrinsic_ssbo_##O;
+   OP(atomic_exchange)
+   OP(atomic_comp_swap)
+   OP(atomic_add)
+   OP(atomic_imin)
+   OP(atomic_umin)
+   OP(atomic_imax)
+   OP(atomic_umax)
+   OP(atomic_and)
+   OP(atomic_or)
+   OP(atomic_xor)
+   OP(atomic_fadd)
+   OP(atomic_fmin)
+   OP(atomic_fmax)
+   OP(atomic_fcomp_swap)
+#undef OP
+   default:
+      unreachable("Invalid SSBO atomic");
+   }
+}
+
+static nir_intrinsic_op
+global_atomic_for_deref(nir_intrinsic_op deref_op)
+{
+   switch (deref_op) {
+#define OP(O) case nir_intrinsic_deref_##O: return nir_intrinsic_global_##O;
+   OP(atomic_exchange)
+   OP(atomic_comp_swap)
+   OP(atomic_add)
+   OP(atomic_imin)
+   OP(atomic_umin)
+   OP(atomic_imax)
+   OP(atomic_umax)
+   OP(atomic_and)
+   OP(atomic_or)
+   OP(atomic_xor)
+   OP(atomic_fadd)
+   OP(atomic_fmin)
+   OP(atomic_fmax)
+   OP(atomic_fcomp_swap)
+#undef OP
+   default:
+      unreachable("Invalid SSBO atomic");
+   }
+}
+
+static nir_intrinsic_op
+shared_atomic_for_deref(nir_intrinsic_op deref_op)
+{
+   switch (deref_op) {
+#define OP(O) case nir_intrinsic_deref_##O: return nir_intrinsic_shared_##O;
+   OP(atomic_exchange)
+   OP(atomic_comp_swap)
+   OP(atomic_add)
+   OP(atomic_imin)
+   OP(atomic_umin)
+   OP(atomic_imax)
+   OP(atomic_umax)
+   OP(atomic_and)
+   OP(atomic_or)
+   OP(atomic_xor)
+   OP(atomic_fadd)
+   OP(atomic_fmin)
+   OP(atomic_fmax)
+   OP(atomic_fcomp_swap)
+#undef OP
+   default:
+      unreachable("Invalid shared atomic");
+   }
+}
+
 void
-nir_assign_var_locations(struct exec_list *var_list, unsigned *size,
-                         int (*type_size)(const struct glsl_type *))
+nir_assign_var_locations(nir_shader *shader, nir_variable_mode mode,
+                         unsigned *size,
+                         int (*type_size)(const struct glsl_type *, bool))
 {
    unsigned location = 0;
 
-   nir_foreach_variable(var, var_list) {
-      /*
-       * UBOs have their own address spaces, so don't count them towards the
-       * number of global uniforms
-       */
-      if ((var->data.mode == nir_var_uniform || var->data.mode == nir_var_shader_storage) &&
-          var->interface_type != NULL)
-         continue;
-
+   nir_foreach_variable_with_modes(var, shader, mode) {
       var->data.driver_location = location;
-      location += type_size(var->type);
+      bool bindless_type_size = var->data.mode == nir_var_shader_in ||
+                                var->data.mode == nir_var_shader_out ||
+                                var->data.bindless;
+      location += type_size(var->type, bindless_type_size);
    }
 
    *size = location;
@@ -86,11 +159,24 @@ nir_is_per_vertex_io(const nir_variable *var, gl_shader_stage stage)
    return false;
 }
 
+static unsigned get_number_of_slots(struct lower_io_state *state,
+                                    const nir_variable *var)
+{
+   const struct glsl_type *type = var->type;
+
+   if (nir_is_per_vertex_io(var, state->builder.shader->info.stage)) {
+      assert(glsl_type_is_array(type));
+      type = glsl_get_array_element(type);
+   }
+
+   return state->type_size(type, var->data.bindless);
+}
+
 static nir_ssa_def *
 get_io_offset(nir_builder *b, nir_deref_instr *deref,
               nir_ssa_def **vertex_index,
-              int (*type_size)(const struct glsl_type *),
-              unsigned *component)
+              int (*type_size)(const struct glsl_type *, bool),
+              unsigned *component, bool bts)
 {
    nir_deref_path path;
    nir_deref_path_init(&path, deref, NULL);
@@ -116,7 +202,7 @@ get_io_offset(nir_builder *b, nir_deref_instr *deref,
       const unsigned total_offset = *component + index;
       const unsigned slot_offset = total_offset / 4;
       *component = total_offset % 4;
-      return nir_imm_int(b, type_size(glsl_vec4_type()) * slot_offset);
+      return nir_imm_int(b, type_size(glsl_vec4_type(), bts) * slot_offset);
    }
 
    /* Just emit code and let constant-folding go to town */
@@ -124,11 +210,10 @@ get_io_offset(nir_builder *b, nir_deref_instr *deref,
 
    for (; *p; p++) {
       if ((*p)->deref_type == nir_deref_type_array) {
-         unsigned size = type_size((*p)->type);
+         unsigned size = type_size((*p)->type, bts);
 
          nir_ssa_def *mul =
-            nir_imul(b, nir_imm_int(b, size),
-                     nir_ssa_for_src(b, (*p)->arr.index, 1));
+            nir_amul_imm(b, nir_ssa_for_src(b, (*p)->arr.index, 1), size);
 
          offset = nir_iadd(b, offset, mul);
       } else if ((*p)->deref_type == nir_deref_type_struct) {
@@ -137,9 +222,9 @@ get_io_offset(nir_builder *b, nir_deref_instr *deref,
 
          unsigned field_offset = 0;
          for (unsigned i = 0; i < (*p)->strct.index; i++) {
-            field_offset += type_size(glsl_get_struct_field(parent->type, i));
+            field_offset += type_size(glsl_get_struct_field(parent->type, i), bts);
          }
-         offset = nir_iadd(b, offset, nir_imm_int(b, field_offset));
+         offset = nir_iadd_imm(b, offset, field_offset);
       } else {
          unreachable("Unsupported deref type");
       }
@@ -150,12 +235,14 @@ get_io_offset(nir_builder *b, nir_deref_instr *deref,
    return offset;
 }
 
-static nir_intrinsic_instr *
-lower_load(nir_intrinsic_instr *intrin, struct lower_io_state *state,
-           nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
-           unsigned component)
+static nir_ssa_def *
+emit_load(struct lower_io_state *state,
+          nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
+          unsigned component, unsigned num_components, unsigned bit_size,
+          nir_alu_type type)
 {
-   const nir_shader *nir = state->builder.shader;
+   nir_builder *b = &state->builder;
+   const nir_shader *nir = b->shader;
    nir_variable_mode mode = var->data.mode;
    nir_ssa_def *barycentric = NULL;
 
@@ -165,20 +252,25 @@ lower_load(nir_intrinsic_instr *intrin, struct lower_io_state *state,
       if (nir->info.stage == MESA_SHADER_FRAGMENT &&
           nir->options->use_interpolated_input_intrinsics &&
           var->data.interpolation != INTERP_MODE_FLAT) {
-         assert(vertex_index == NULL);
-
-         nir_intrinsic_op bary_op;
-         if (var->data.sample ||
-             (state->options & nir_lower_io_force_sample_interpolation))
-            bary_op = nir_intrinsic_load_barycentric_sample;
-         else if (var->data.centroid)
-            bary_op = nir_intrinsic_load_barycentric_centroid;
-         else
-            bary_op = nir_intrinsic_load_barycentric_pixel;
-
-         barycentric = nir_load_barycentric(&state->builder, bary_op,
-                                            var->data.interpolation);
-         op = nir_intrinsic_load_interpolated_input;
+         if (var->data.interpolation == INTERP_MODE_EXPLICIT) {
+            assert(vertex_index != NULL);
+            op = nir_intrinsic_load_input_vertex;
+         } else {
+            assert(vertex_index == NULL);
+
+            nir_intrinsic_op bary_op;
+            if (var->data.sample ||
+                (state->options & nir_lower_io_force_sample_interpolation))
+               bary_op = nir_intrinsic_load_barycentric_sample;
+            else if (var->data.centroid)
+               bary_op = nir_intrinsic_load_barycentric_centroid;
+            else
+               bary_op = nir_intrinsic_load_barycentric_pixel;
+
+            barycentric = nir_load_barycentric(&state->builder, bary_op,
+                                               var->data.interpolation);
+            op = nir_intrinsic_load_interpolated_input;
+         }
       } else {
          op = vertex_index ? nir_intrinsic_load_per_vertex_input :
                              nir_intrinsic_load_input;
@@ -191,23 +283,34 @@ lower_load(nir_intrinsic_instr *intrin, struct lower_io_state *state,
    case nir_var_uniform:
       op = nir_intrinsic_load_uniform;
       break;
-   case nir_var_shared:
-      op = nir_intrinsic_load_shared;
-      break;
    default:
       unreachable("Unknown variable mode");
    }
 
    nir_intrinsic_instr *load =
       nir_intrinsic_instr_create(state->builder.shader, op);
-   load->num_components = intrin->num_components;
+   load->num_components = num_components;
 
    nir_intrinsic_set_base(load, var->data.driver_location);
    if (mode == nir_var_shader_in || mode == nir_var_shader_out)
       nir_intrinsic_set_component(load, component);
 
    if (load->intrinsic == nir_intrinsic_load_uniform)
-      nir_intrinsic_set_range(load, state->type_size(var->type));
+      nir_intrinsic_set_range(load,
+                              state->type_size(var->type, var->data.bindless));
+
+   if (load->intrinsic == nir_intrinsic_load_input ||
+       load->intrinsic == nir_intrinsic_load_input_vertex ||
+       load->intrinsic == nir_intrinsic_load_uniform)
+      nir_intrinsic_set_type(load, type);
+
+   if (load->intrinsic != nir_intrinsic_load_uniform) {
+      nir_io_semantics semantics = {0};
+      semantics.location = var->data.location;
+      semantics.num_slots = get_number_of_slots(state, var);
+      semantics.fb_fetch_output = var->data.fb_fetch_output;
+      nir_intrinsic_set_io_semantics(load, semantics);
+   }
 
    if (vertex_index) {
       load->src[0] = nir_src_for_ssa(vertex_index);
@@ -219,98 +322,204 @@ lower_load(nir_intrinsic_instr *intrin, struct lower_io_state *state,
       load->src[0] = nir_src_for_ssa(offset);
    }
 
-   return load;
+   nir_ssa_dest_init(&load->instr, &load->dest,
+                     num_components, bit_size, NULL);
+   nir_builder_instr_insert(b, &load->instr);
+
+   return &load->dest.ssa;
 }
 
-static nir_intrinsic_instr *
-lower_store(nir_intrinsic_instr *intrin, struct lower_io_state *state,
-            nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
-            unsigned component)
+static nir_ssa_def *
+lower_load(nir_intrinsic_instr *intrin, struct lower_io_state *state,
+           nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
+           unsigned component, const struct glsl_type *type)
 {
-   nir_variable_mode mode = var->data.mode;
+   assert(intrin->dest.is_ssa);
+   if (intrin->dest.ssa.bit_size == 64 &&
+       (state->options & nir_lower_io_lower_64bit_to_32)) {
+      nir_builder *b = &state->builder;
+
+      const unsigned slot_size = state->type_size(glsl_dvec_type(2), false);
+
+      nir_ssa_def *comp64[4];
+      assert(component == 0 || component == 2);
+      unsigned dest_comp = 0;
+      while (dest_comp < intrin->dest.ssa.num_components) {
+         const unsigned num_comps =
+            MIN2(intrin->dest.ssa.num_components - dest_comp,
+                 (4 - component) / 2);
+
+         nir_ssa_def *data32 =
+            emit_load(state, vertex_index, var, offset, component,
+                      num_comps * 2, 32, nir_type_uint32);
+         for (unsigned i = 0; i < num_comps; i++) {
+            comp64[dest_comp + i] =
+               nir_pack_64_2x32(b, nir_channels(b, data32, 3 << (i * 2)));
+         }
 
-   nir_intrinsic_op op;
-   if (mode == nir_var_shared) {
-      op = nir_intrinsic_store_shared;
+         /* Only the first store has a component offset */
+         component = 0;
+         dest_comp += num_comps;
+         offset = nir_iadd_imm(b, offset, slot_size);
+      }
+
+      return nir_vec(b, comp64, intrin->dest.ssa.num_components);
+   } else if (intrin->dest.ssa.bit_size == 1) {
+      /* Booleans are 32-bit */
+      assert(glsl_type_is_boolean(type));
+      return nir_b2b1(&state->builder,
+                      emit_load(state, vertex_index, var, offset, component,
+                                intrin->dest.ssa.num_components, 32,
+                                nir_type_bool32));
    } else {
-      assert(mode == nir_var_shader_out);
-      op = vertex_index ? nir_intrinsic_store_per_vertex_output :
-                          nir_intrinsic_store_output;
+      return emit_load(state, vertex_index, var, offset, component,
+                       intrin->dest.ssa.num_components,
+                       intrin->dest.ssa.bit_size,
+                       nir_get_nir_type_for_glsl_type(type));
    }
+}
+
+static void
+emit_store(struct lower_io_state *state, nir_ssa_def *data,
+           nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
+           unsigned component, unsigned num_components,
+           nir_component_mask_t write_mask, nir_alu_type type)
+{
+   nir_builder *b = &state->builder;
+   nir_variable_mode mode = var->data.mode;
+
+   assert(mode == nir_var_shader_out);
+   nir_intrinsic_op op;
+   op = vertex_index ? nir_intrinsic_store_per_vertex_output :
+                       nir_intrinsic_store_output;
 
    nir_intrinsic_instr *store =
       nir_intrinsic_instr_create(state->builder.shader, op);
-   store->num_components = intrin->num_components;
+   store->num_components = num_components;
 
-   nir_src_copy(&store->src[0], &intrin->src[1], store);
+   store->src[0] = nir_src_for_ssa(data);
 
    nir_intrinsic_set_base(store, var->data.driver_location);
 
    if (mode == nir_var_shader_out)
       nir_intrinsic_set_component(store, component);
 
-   nir_intrinsic_set_write_mask(store, nir_intrinsic_write_mask(intrin));
+   if (store->intrinsic == nir_intrinsic_store_output)
+      nir_intrinsic_set_type(store, type);
+
+   nir_intrinsic_set_write_mask(store, write_mask);
 
    if (vertex_index)
       store->src[1] = nir_src_for_ssa(vertex_index);
 
    store->src[vertex_index ? 2 : 1] = nir_src_for_ssa(offset);
 
-   return store;
-}
-
-static nir_intrinsic_instr *
-lower_atomic(nir_intrinsic_instr *intrin, struct lower_io_state *state,
-             nir_variable *var, nir_ssa_def *offset)
-{
-   assert(var->data.mode == nir_var_shared);
-
-   nir_intrinsic_op op;
-   switch (intrin->intrinsic) {
-#define OP(O) case nir_intrinsic_deref_##O: op = nir_intrinsic_shared_##O; break;
-   OP(atomic_exchange)
-   OP(atomic_comp_swap)
-   OP(atomic_add)
-   OP(atomic_imin)
-   OP(atomic_umin)
-   OP(atomic_imax)
-   OP(atomic_umax)
-   OP(atomic_and)
-   OP(atomic_or)
-   OP(atomic_xor)
-   OP(atomic_fadd)
-   OP(atomic_fmin)
-   OP(atomic_fmax)
-   OP(atomic_fcomp_swap)
-#undef OP
-   default:
-      unreachable("Invalid atomic");
+   unsigned gs_streams = 0;
+   if (state->builder.shader->info.stage == MESA_SHADER_GEOMETRY) {
+      if (var->data.stream & NIR_STREAM_PACKED) {
+         gs_streams = var->data.stream & ~NIR_STREAM_PACKED;
+      } else {
+         assert(var->data.stream < 4);
+         gs_streams = 0;
+         for (unsigned i = 0; i < num_components; ++i)
+            gs_streams |= var->data.stream << (2 * i);
+      }
    }
 
-   nir_intrinsic_instr *atomic =
-      nir_intrinsic_instr_create(state->builder.shader, op);
+   nir_io_semantics semantics = {0};
+   semantics.location = var->data.location;
+   semantics.num_slots = get_number_of_slots(state, var);
+   semantics.dual_source_blend_index = var->data.index;
+   semantics.gs_streams = gs_streams;
+   nir_intrinsic_set_io_semantics(store, semantics);
 
-   nir_intrinsic_set_base(atomic, var->data.driver_location);
+   nir_builder_instr_insert(b, &store->instr);
+}
 
-   atomic->src[0] = nir_src_for_ssa(offset);
-   assert(nir_intrinsic_infos[intrin->intrinsic].num_srcs ==
-          nir_intrinsic_infos[op].num_srcs);
-   for (unsigned i = 1; i < nir_intrinsic_infos[op].num_srcs; i++) {
-      nir_src_copy(&atomic->src[i], &intrin->src[i], atomic);
-   }
+static void
+lower_store(nir_intrinsic_instr *intrin, struct lower_io_state *state,
+            nir_ssa_def *vertex_index, nir_variable *var, nir_ssa_def *offset,
+            unsigned component, const struct glsl_type *type)
+{
+   assert(intrin->src[1].is_ssa);
+   if (intrin->src[1].ssa->bit_size == 64 &&
+       (state->options & nir_lower_io_lower_64bit_to_32)) {
+      nir_builder *b = &state->builder;
+
+      const unsigned slot_size = state->type_size(glsl_dvec_type(2), false);
+
+      assert(component == 0 || component == 2);
+      unsigned src_comp = 0;
+      nir_component_mask_t write_mask = nir_intrinsic_write_mask(intrin);
+      while (src_comp < intrin->num_components) {
+         const unsigned num_comps =
+            MIN2(intrin->num_components - src_comp,
+                 (4 - component) / 2);
+
+         if (write_mask & BITFIELD_MASK(num_comps)) {
+            nir_ssa_def *data =
+               nir_channels(b, intrin->src[1].ssa,
+                            BITFIELD_RANGE(src_comp, num_comps));
+            nir_ssa_def *data32 = nir_bitcast_vector(b, data, 32);
+
+            nir_component_mask_t write_mask32 = 0;
+            for (unsigned i = 0; i < num_comps; i++) {
+               if (write_mask & BITFIELD_MASK(num_comps) & (1 << i))
+                  write_mask32 |= 3 << (i * 2);
+            }
+
+            emit_store(state, data32, vertex_index, var, offset,
+                       component, data32->num_components, write_mask32,
+                       nir_type_uint32);
+         }
 
-   return atomic;
+         /* Only the first store has a component offset */
+         component = 0;
+         src_comp += num_comps;
+         write_mask >>= num_comps;
+         offset = nir_iadd_imm(b, offset, slot_size);
+      }
+   } else if (intrin->dest.ssa.bit_size == 1) {
+      /* Booleans are 32-bit */
+      assert(glsl_type_is_boolean(type));
+      nir_ssa_def *b32_val = nir_b2b32(&state->builder, intrin->src[1].ssa);
+      emit_store(state, b32_val, vertex_index, var, offset,
+                 component, intrin->num_components,
+                 nir_intrinsic_write_mask(intrin),
+                 nir_type_bool32);
+   } else {
+      emit_store(state, intrin->src[1].ssa, vertex_index, var, offset,
+                 component, intrin->num_components,
+                 nir_intrinsic_write_mask(intrin),
+                 nir_get_nir_type_for_glsl_type(type));
+   }
 }
 
-static nir_intrinsic_instr *
+static nir_ssa_def *
 lower_interpolate_at(nir_intrinsic_instr *intrin, struct lower_io_state *state,
-                     nir_variable *var, nir_ssa_def *offset, unsigned component)
+                     nir_variable *var, nir_ssa_def *offset, unsigned component,
+                     const struct glsl_type *type)
 {
+   nir_builder *b = &state->builder;
    assert(var->data.mode == nir_var_shader_in);
 
-   /* Ignore interpolateAt() for flat variables - flat is flat. */
-   if (var->data.interpolation == INTERP_MODE_FLAT)
-      return lower_load(intrin, state, NULL, var, offset, component);
+   /* Ignore interpolateAt() for flat variables - flat is flat. Lower
+    * interpolateAtVertex() for explicit variables.
+    */
+   if (var->data.interpolation == INTERP_MODE_FLAT ||
+       var->data.interpolation == INTERP_MODE_EXPLICIT) {
+      nir_ssa_def *vertex_index = NULL;
+
+      if (var->data.interpolation == INTERP_MODE_EXPLICIT) {
+         assert(intrin->intrinsic == nir_intrinsic_interp_deref_at_vertex);
+         vertex_index = intrin->src[1].ssa;
+      }
+
+      return lower_load(intrin, state, vertex_index, var, offset, component, type);
+   }
+
+   /* None of the supported APIs allow interpolation on 64-bit things */
+   assert(intrin->dest.is_ssa && intrin->dest.ssa.bit_size <= 32);
 
    nir_intrinsic_op bary_op;
    switch (intrin->intrinsic) {
@@ -336,10 +545,11 @@ lower_interpolate_at(nir_intrinsic_instr *intrin, struct lower_io_state *state,
    nir_intrinsic_set_interp_mode(bary_setup, var->data.interpolation);
 
    if (intrin->intrinsic == nir_intrinsic_interp_deref_at_sample ||
-       intrin->intrinsic == nir_intrinsic_interp_deref_at_offset)
+       intrin->intrinsic == nir_intrinsic_interp_deref_at_offset ||
+       intrin->intrinsic == nir_intrinsic_interp_deref_at_vertex)
       nir_src_copy(&bary_setup->src[0], &intrin->src[1], bary_setup);
 
-   nir_builder_instr_insert(&state->builder, &bary_setup->instr);
+   nir_builder_instr_insert(b, &bary_setup->instr);
 
    nir_intrinsic_instr *load =
       nir_intrinsic_instr_create(state->builder.shader,
@@ -349,10 +559,21 @@ lower_interpolate_at(nir_intrinsic_instr *intrin, struct lower_io_state *state,
    nir_intrinsic_set_base(load, var->data.driver_location);
    nir_intrinsic_set_component(load, component);
 
+   nir_io_semantics semantics = {0};
+   semantics.location = var->data.location;
+   semantics.num_slots = get_number_of_slots(state, var);
+   nir_intrinsic_set_io_semantics(load, semantics);
+
    load->src[0] = nir_src_for_ssa(&bary_setup->dest.ssa);
    load->src[1] = nir_src_for_ssa(offset);
 
-   return load;
+   assert(intrin->dest.is_ssa);
+   nir_ssa_dest_init(&load->instr, &load->dest,
+                     intrin->dest.ssa.num_components,
+                     intrin->dest.ssa.bit_size, NULL);
+   nir_builder_instr_insert(b, &load->instr);
+
+   return &load->dest.ssa;
 }
 
 static bool
@@ -372,25 +593,12 @@ nir_lower_io_block(nir_block *block,
       switch (intrin->intrinsic) {
       case nir_intrinsic_load_deref:
       case nir_intrinsic_store_deref:
-      case nir_intrinsic_deref_atomic_add:
-      case nir_intrinsic_deref_atomic_imin:
-      case nir_intrinsic_deref_atomic_umin:
-      case nir_intrinsic_deref_atomic_imax:
-      case nir_intrinsic_deref_atomic_umax:
-      case nir_intrinsic_deref_atomic_and:
-      case nir_intrinsic_deref_atomic_or:
-      case nir_intrinsic_deref_atomic_xor:
-      case nir_intrinsic_deref_atomic_exchange:
-      case nir_intrinsic_deref_atomic_comp_swap:
-      case nir_intrinsic_deref_atomic_fadd:
-      case nir_intrinsic_deref_atomic_fmin:
-      case nir_intrinsic_deref_atomic_fmax:
-      case nir_intrinsic_deref_atomic_fcomp_swap:
          /* We can lower the io for this nir instrinsic */
          break;
       case nir_intrinsic_interp_deref_at_centroid:
       case nir_intrinsic_interp_deref_at_sample:
       case nir_intrinsic_interp_deref_at_offset:
+      case nir_intrinsic_interp_deref_at_vertex:
          /* We can optionally lower these to load_interpolated_input */
          if (options->use_interpolated_input_intrinsics)
             break;
@@ -401,17 +609,12 @@ nir_lower_io_block(nir_block *block,
 
       nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
 
-      nir_variable *var = nir_deref_instr_get_variable(deref);
-      nir_variable_mode mode = var->data.mode;
-
+      nir_variable_mode mode = deref->mode;
+      assert(util_is_power_of_two_nonzero(mode));
       if ((state->modes & mode) == 0)
          continue;
 
-      if (mode != nir_var_shader_in &&
-          mode != nir_var_shader_out &&
-          mode != nir_var_shared &&
-          mode != nir_var_uniform)
-         continue;
+      nir_variable *var = nir_deref_instr_get_variable(deref);
 
       b->cursor = nir_before_instr(instr);
 
@@ -420,66 +623,44 @@ nir_lower_io_block(nir_block *block,
       nir_ssa_def *offset;
       nir_ssa_def *vertex_index = NULL;
       unsigned component_offset = var->data.location_frac;
+      bool bindless_type_size = mode == nir_var_shader_in ||
+                                mode == nir_var_shader_out ||
+                                var->data.bindless;
 
       offset = get_io_offset(b, deref, per_vertex ? &vertex_index : NULL,
-                             state->type_size, &component_offset);
+                             state->type_size, &component_offset,
+                             bindless_type_size);
 
-      nir_intrinsic_instr *replacement;
+      nir_ssa_def *replacement = NULL;
 
       switch (intrin->intrinsic) {
       case nir_intrinsic_load_deref:
          replacement = lower_load(intrin, state, vertex_index, var, offset,
-                                  component_offset);
+                                  component_offset, deref->type);
          break;
 
       case nir_intrinsic_store_deref:
-         replacement = lower_store(intrin, state, vertex_index, var, offset,
-                                   component_offset);
-         break;
-
-      case nir_intrinsic_deref_atomic_add:
-      case nir_intrinsic_deref_atomic_imin:
-      case nir_intrinsic_deref_atomic_umin:
-      case nir_intrinsic_deref_atomic_imax:
-      case nir_intrinsic_deref_atomic_umax:
-      case nir_intrinsic_deref_atomic_and:
-      case nir_intrinsic_deref_atomic_or:
-      case nir_intrinsic_deref_atomic_xor:
-      case nir_intrinsic_deref_atomic_exchange:
-      case nir_intrinsic_deref_atomic_comp_swap:
-      case nir_intrinsic_deref_atomic_fadd:
-      case nir_intrinsic_deref_atomic_fmin:
-      case nir_intrinsic_deref_atomic_fmax:
-      case nir_intrinsic_deref_atomic_fcomp_swap:
-         assert(vertex_index == NULL);
-         replacement = lower_atomic(intrin, state, var, offset);
+         lower_store(intrin, state, vertex_index, var, offset,
+                     component_offset, deref->type);
          break;
 
       case nir_intrinsic_interp_deref_at_centroid:
       case nir_intrinsic_interp_deref_at_sample:
       case nir_intrinsic_interp_deref_at_offset:
+      case nir_intrinsic_interp_deref_at_vertex:
          assert(vertex_index == NULL);
          replacement = lower_interpolate_at(intrin, state, var, offset,
-                                            component_offset);
+                                            component_offset, deref->type);
          break;
 
       default:
          continue;
       }
 
-      if (nir_intrinsic_infos[intrin->intrinsic].has_dest) {
-         if (intrin->dest.is_ssa) {
-            nir_ssa_dest_init(&replacement->instr, &replacement->dest,
-                              intrin->dest.ssa.num_components,
-                              intrin->dest.ssa.bit_size, NULL);
-            nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
-                                     nir_src_for_ssa(&replacement->dest.ssa));
-         } else {
-            nir_dest_copy(&replacement->dest, &intrin->dest, &intrin->instr);
-         }
+      if (replacement) {
+         nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
+                                  nir_src_for_ssa(replacement));
       }
-
-      nir_instr_insert_before(&intrin->instr, &replacement->instr);
       nir_instr_remove(&intrin->instr);
       progress = true;
    }
@@ -490,7 +671,7 @@ nir_lower_io_block(nir_block *block,
 static bool
 nir_lower_io_impl(nir_function_impl *impl,
                   nir_variable_mode modes,
-                  int (*type_size)(const struct glsl_type *),
+                  int (*type_size)(const struct glsl_type *, bool),
                   nir_lower_io_options options)
 {
    struct lower_io_state state;
@@ -502,6 +683,10 @@ nir_lower_io_impl(nir_function_impl *impl,
    state.type_size = type_size;
    state.options = options;
 
+   ASSERTED nir_variable_mode supported_modes =
+      nir_var_shader_in | nir_var_shader_out | nir_var_uniform;
+   assert(!(modes & ~supported_modes));
+
    nir_foreach_block(block, impl) {
       progress |= nir_lower_io_block(block, &state);
    }
@@ -513,9 +698,18 @@ nir_lower_io_impl(nir_function_impl *impl,
    return progress;
 }
 
+/** Lower load/store_deref intrinsics on I/O variables to offset-based intrinsics
+ *
+ * This pass is intended to be used for cross-stage shader I/O and driver-
+ * managed uniforms to turn deref-based access into a simpler model using
+ * locations or offsets.  For fragment shader inputs, it can optionally turn
+ * load_deref into an explicit interpolation using barycentrics coming from
+ * one of the load_barycentric_* intrinsics.  This pass requires that all
+ * deref chains are complete and contain no casts.
+ */
 bool
 nir_lower_io(nir_shader *shader, nir_variable_mode modes,
-             int (*type_size)(const struct glsl_type *),
+             int (*type_size)(const struct glsl_type *, bool),
              nir_lower_io_options options)
 {
    bool progress = false;
@@ -530,45 +724,1209 @@ nir_lower_io(nir_shader *shader, nir_variable_mode modes,
    return progress;
 }
 
-/**
- * Return the offset source for a load/store intrinsic.
- */
-nir_src *
-nir_get_io_offset_src(nir_intrinsic_instr *instr)
+static unsigned
+type_scalar_size_bytes(const struct glsl_type *type)
 {
-   switch (instr->intrinsic) {
-   case nir_intrinsic_load_input:
-   case nir_intrinsic_load_output:
-   case nir_intrinsic_load_uniform:
-      return &instr->src[0];
-   case nir_intrinsic_load_ubo:
-   case nir_intrinsic_load_ssbo:
-   case nir_intrinsic_load_per_vertex_input:
-   case nir_intrinsic_load_per_vertex_output:
-   case nir_intrinsic_load_interpolated_input:
-   case nir_intrinsic_store_output:
-      return &instr->src[1];
-   case nir_intrinsic_store_ssbo:
-   case nir_intrinsic_store_per_vertex_output:
-      return &instr->src[2];
+   assert(glsl_type_is_vector_or_scalar(type) ||
+          glsl_type_is_matrix(type));
+   return glsl_type_is_boolean(type) ? 4 : glsl_get_bit_size(type) / 8;
+}
+
+static nir_ssa_def *
+build_addr_iadd(nir_builder *b, nir_ssa_def *addr,
+                nir_address_format addr_format, nir_ssa_def *offset)
+{
+   assert(offset->num_components == 1);
+
+   switch (addr_format) {
+   case nir_address_format_32bit_global:
+   case nir_address_format_64bit_global:
+   case nir_address_format_32bit_offset:
+      assert(addr->bit_size == offset->bit_size);
+      assert(addr->num_components == 1);
+      return nir_iadd(b, addr, offset);
+
+   case nir_address_format_32bit_offset_as_64bit:
+      assert(addr->num_components == 1);
+      assert(offset->bit_size == 32);
+      return nir_u2u64(b, nir_iadd(b, nir_u2u32(b, addr), offset));
+
+   case nir_address_format_64bit_bounded_global:
+      assert(addr->num_components == 4);
+      assert(addr->bit_size == offset->bit_size);
+      return nir_vec4(b, nir_channel(b, addr, 0),
+                         nir_channel(b, addr, 1),
+                         nir_channel(b, addr, 2),
+                         nir_iadd(b, nir_channel(b, addr, 3), offset));
+
+   case nir_address_format_32bit_index_offset:
+      assert(addr->num_components == 2);
+      assert(addr->bit_size == offset->bit_size);
+      return nir_vec2(b, nir_channel(b, addr, 0),
+                         nir_iadd(b, nir_channel(b, addr, 1), offset));
+
+   case nir_address_format_32bit_index_offset_pack64:
+      assert(addr->num_components == 1);
+      assert(offset->bit_size == 32);
+      return nir_pack_64_2x32_split(b,
+                                    nir_iadd(b, nir_unpack_64_2x32_split_x(b, addr), offset),
+                                    nir_unpack_64_2x32_split_y(b, addr));
+
+   case nir_address_format_vec2_index_32bit_offset:
+      assert(addr->num_components == 3);
+      assert(offset->bit_size == 32);
+      return nir_vec3(b, nir_channel(b, addr, 0), nir_channel(b, addr, 1),
+                         nir_iadd(b, nir_channel(b, addr, 2), offset));
+
+   case nir_address_format_logical:
+      unreachable("Unsupported address format");
+   }
+   unreachable("Invalid address format");
+}
+
+static unsigned
+addr_get_offset_bit_size(nir_ssa_def *addr, nir_address_format addr_format)
+{
+   if (addr_format == nir_address_format_32bit_offset_as_64bit ||
+       addr_format == nir_address_format_32bit_index_offset_pack64)
+      return 32;
+   return addr->bit_size;
+}
+
+static nir_ssa_def *
+build_addr_iadd_imm(nir_builder *b, nir_ssa_def *addr,
+                    nir_address_format addr_format, int64_t offset)
+{
+   return build_addr_iadd(b, addr, addr_format,
+                             nir_imm_intN_t(b, offset,
+                                            addr_get_offset_bit_size(addr, addr_format)));
+}
+
+static nir_ssa_def *
+build_addr_for_var(nir_builder *b, nir_variable *var,
+                   nir_address_format addr_format)
+{
+   assert(var->data.mode & (nir_var_uniform | nir_var_mem_shared |
+                            nir_var_shader_temp | nir_var_function_temp));
+
+   const unsigned num_comps = nir_address_format_num_components(addr_format);
+   const unsigned bit_size = nir_address_format_bit_size(addr_format);
+
+   switch (addr_format) {
+   case nir_address_format_32bit_global:
+   case nir_address_format_64bit_global: {
+      nir_ssa_def *base_addr;
+      switch (var->data.mode) {
+      case nir_var_shader_temp:
+         base_addr = nir_load_scratch_base_ptr(b, 0, num_comps, bit_size);
+         break;
+
+      case nir_var_function_temp:
+         base_addr = nir_load_scratch_base_ptr(b, 1, num_comps, bit_size);
+         break;
+
+      default:
+         unreachable("Unsupported variable mode");
+      }
+
+      return build_addr_iadd_imm(b, base_addr, addr_format,
+                                    var->data.driver_location);
+   }
+
+   case nir_address_format_32bit_offset:
+      assert(var->data.driver_location <= UINT32_MAX);
+      return nir_imm_int(b, var->data.driver_location);
+
+   case nir_address_format_32bit_offset_as_64bit:
+      assert(var->data.driver_location <= UINT32_MAX);
+      return nir_imm_int64(b, var->data.driver_location);
+
    default:
-      return NULL;
+      unreachable("Unsupported address format");
    }
 }
 
-/**
- * Return the vertex index source for a load/store per_vertex intrinsic.
- */
-nir_src *
-nir_get_io_vertex_index_src(nir_intrinsic_instr *instr)
+static nir_ssa_def *
+addr_to_index(nir_builder *b, nir_ssa_def *addr,
+              nir_address_format addr_format)
 {
-   switch (instr->intrinsic) {
-   case nir_intrinsic_load_per_vertex_input:
-   case nir_intrinsic_load_per_vertex_output:
-      return &instr->src[0];
-   case nir_intrinsic_store_per_vertex_output:
-      return &instr->src[1];
+   switch (addr_format) {
+   case nir_address_format_32bit_index_offset:
+      assert(addr->num_components == 2);
+      return nir_channel(b, addr, 0);
+   case nir_address_format_32bit_index_offset_pack64:
+      return nir_unpack_64_2x32_split_y(b, addr);
+   case nir_address_format_vec2_index_32bit_offset:
+      assert(addr->num_components == 3);
+      return nir_channels(b, addr, 0x3);
+   default: unreachable("Invalid address format");
+   }
+}
+
+static nir_ssa_def *
+addr_to_offset(nir_builder *b, nir_ssa_def *addr,
+               nir_address_format addr_format)
+{
+   switch (addr_format) {
+   case nir_address_format_32bit_index_offset:
+      assert(addr->num_components == 2);
+      return nir_channel(b, addr, 1);
+   case nir_address_format_32bit_index_offset_pack64:
+      return nir_unpack_64_2x32_split_x(b, addr);
+   case nir_address_format_vec2_index_32bit_offset:
+      assert(addr->num_components == 3);
+      return nir_channel(b, addr, 2);
+   case nir_address_format_32bit_offset:
+      return addr;
+   case nir_address_format_32bit_offset_as_64bit:
+      return nir_u2u32(b, addr);
    default:
-      return NULL;
+      unreachable("Invalid address format");
+   }
+}
+
+/** Returns true if the given address format resolves to a global address */
+static bool
+addr_format_is_global(nir_address_format addr_format)
+{
+   return addr_format == nir_address_format_32bit_global ||
+          addr_format == nir_address_format_64bit_global ||
+          addr_format == nir_address_format_64bit_bounded_global;
+}
+
+static bool
+addr_format_is_offset(nir_address_format addr_format)
+{
+   return addr_format == nir_address_format_32bit_offset ||
+          addr_format == nir_address_format_32bit_offset_as_64bit;
+}
+
+static nir_ssa_def *
+addr_to_global(nir_builder *b, nir_ssa_def *addr,
+               nir_address_format addr_format)
+{
+   switch (addr_format) {
+   case nir_address_format_32bit_global:
+   case nir_address_format_64bit_global:
+      assert(addr->num_components == 1);
+      return addr;
+
+   case nir_address_format_64bit_bounded_global:
+      assert(addr->num_components == 4);
+      return nir_iadd(b, nir_pack_64_2x32(b, nir_channels(b, addr, 0x3)),
+                         nir_u2u64(b, nir_channel(b, addr, 3)));
+
+   case nir_address_format_32bit_index_offset:
+   case nir_address_format_32bit_index_offset_pack64:
+   case nir_address_format_vec2_index_32bit_offset:
+   case nir_address_format_32bit_offset:
+   case nir_address_format_32bit_offset_as_64bit:
+   case nir_address_format_logical:
+      unreachable("Cannot get a 64-bit address with this address format");
    }
+
+   unreachable("Invalid address format");
+}
+
+static bool
+addr_format_needs_bounds_check(nir_address_format addr_format)
+{
+   return addr_format == nir_address_format_64bit_bounded_global;
+}
+
+static nir_ssa_def *
+addr_is_in_bounds(nir_builder *b, nir_ssa_def *addr,
+                  nir_address_format addr_format, unsigned size)
+{
+   assert(addr_format == nir_address_format_64bit_bounded_global);
+   assert(addr->num_components == 4);
+   return nir_ige(b, nir_channel(b, addr, 2),
+                     nir_iadd_imm(b, nir_channel(b, addr, 3), size));
 }
+
+static nir_ssa_def *
+build_explicit_io_load(nir_builder *b, nir_intrinsic_instr *intrin,
+                       nir_ssa_def *addr, nir_address_format addr_format,
+                       unsigned num_components)
+{
+   nir_variable_mode mode = nir_src_as_deref(intrin->src[0])->mode;
+
+   nir_intrinsic_op op;
+   switch (mode) {
+   case nir_var_mem_ubo:
+      op = nir_intrinsic_load_ubo;
+      break;
+   case nir_var_mem_ssbo:
+      if (addr_format_is_global(addr_format))
+         op = nir_intrinsic_load_global;
+      else
+         op = nir_intrinsic_load_ssbo;
+      break;
+   case nir_var_mem_global:
+      assert(addr_format_is_global(addr_format));
+      op = nir_intrinsic_load_global;
+      break;
+   case nir_var_uniform:
+      assert(addr_format_is_offset(addr_format));
+      assert(b->shader->info.stage == MESA_SHADER_KERNEL);
+      op = nir_intrinsic_load_kernel_input;
+      break;
+   case nir_var_mem_shared:
+      assert(addr_format_is_offset(addr_format));
+      op = nir_intrinsic_load_shared;
+      break;
+   case nir_var_shader_temp:
+   case nir_var_function_temp:
+      if (addr_format_is_offset(addr_format)) {
+         op = nir_intrinsic_load_scratch;
+      } else {
+         assert(addr_format_is_global(addr_format));
+         op = nir_intrinsic_load_global;
+      }
+      break;
+   default:
+      unreachable("Unsupported explicit IO variable mode");
+   }
+
+   nir_intrinsic_instr *load = nir_intrinsic_instr_create(b->shader, op);
+
+   if (addr_format_is_global(addr_format)) {
+      load->src[0] = nir_src_for_ssa(addr_to_global(b, addr, addr_format));
+   } else if (addr_format_is_offset(addr_format)) {
+      assert(addr->num_components == 1);
+      load->src[0] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   } else {
+      load->src[0] = nir_src_for_ssa(addr_to_index(b, addr, addr_format));
+      load->src[1] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   }
+
+   if (nir_intrinsic_has_access(load))
+      nir_intrinsic_set_access(load, nir_intrinsic_access(intrin));
+
+   unsigned bit_size = intrin->dest.ssa.bit_size;
+   if (bit_size == 1) {
+      /* TODO: Make the native bool bit_size an option. */
+      bit_size = 32;
+   }
+
+   /* TODO: We should try and provide a better alignment.  For OpenCL, we need
+    * to plumb the alignment through from SPIR-V when we have one.
+    */
+   nir_intrinsic_set_align(load, bit_size / 8, 0);
+
+   assert(intrin->dest.is_ssa);
+   load->num_components = num_components;
+   nir_ssa_dest_init(&load->instr, &load->dest, num_components,
+                     bit_size, intrin->dest.ssa.name);
+
+   assert(bit_size % 8 == 0);
+
+   nir_ssa_def *result;
+   if (addr_format_needs_bounds_check(addr_format)) {
+      /* The Vulkan spec for robustBufferAccess gives us quite a few options
+       * as to what we can do with an OOB read.  Unfortunately, returning
+       * undefined values isn't one of them so we return an actual zero.
+       */
+      nir_ssa_def *zero = nir_imm_zero(b, load->num_components, bit_size);
+
+      const unsigned load_size = (bit_size / 8) * load->num_components;
+      nir_push_if(b, addr_is_in_bounds(b, addr, addr_format, load_size));
+
+      nir_builder_instr_insert(b, &load->instr);
+
+      nir_pop_if(b, NULL);
+
+      result = nir_if_phi(b, &load->dest.ssa, zero);
+   } else {
+      nir_builder_instr_insert(b, &load->instr);
+      result = &load->dest.ssa;
+   }
+
+   if (intrin->dest.ssa.bit_size == 1) {
+      /* For shared, we can go ahead and use NIR's and/or the back-end's
+       * standard encoding for booleans rather than forcing a 0/1 boolean.
+       * This should save an instruction or two.
+       */
+      if (mode == nir_var_mem_shared ||
+          mode == nir_var_shader_temp ||
+          mode == nir_var_function_temp)
+         result = nir_b2b1(b, result);
+      else
+         result = nir_i2b(b, result);
+   }
+
+   return result;
+}
+
+static void
+build_explicit_io_store(nir_builder *b, nir_intrinsic_instr *intrin,
+                        nir_ssa_def *addr, nir_address_format addr_format,
+                        nir_ssa_def *value, nir_component_mask_t write_mask)
+{
+   nir_variable_mode mode = nir_src_as_deref(intrin->src[0])->mode;
+
+   nir_intrinsic_op op;
+   switch (mode) {
+   case nir_var_mem_ssbo:
+      if (addr_format_is_global(addr_format))
+         op = nir_intrinsic_store_global;
+      else
+         op = nir_intrinsic_store_ssbo;
+      break;
+   case nir_var_mem_global:
+      assert(addr_format_is_global(addr_format));
+      op = nir_intrinsic_store_global;
+      break;
+   case nir_var_mem_shared:
+      assert(addr_format_is_offset(addr_format));
+      op = nir_intrinsic_store_shared;
+      break;
+   case nir_var_shader_temp:
+   case nir_var_function_temp:
+      if (addr_format_is_offset(addr_format)) {
+         op = nir_intrinsic_store_scratch;
+      } else {
+         assert(addr_format_is_global(addr_format));
+         op = nir_intrinsic_store_global;
+      }
+      break;
+   default:
+      unreachable("Unsupported explicit IO variable mode");
+   }
+
+   nir_intrinsic_instr *store = nir_intrinsic_instr_create(b->shader, op);
+
+   if (value->bit_size == 1) {
+      /* For shared, we can go ahead and use NIR's and/or the back-end's
+       * standard encoding for booleans rather than forcing a 0/1 boolean.
+       * This should save an instruction or two.
+       *
+       * TODO: Make the native bool bit_size an option.
+       */
+      if (mode == nir_var_mem_shared ||
+          mode == nir_var_shader_temp ||
+          mode == nir_var_function_temp)
+         value = nir_b2b32(b, value);
+      else
+         value = nir_b2i(b, value, 32);
+   }
+
+   store->src[0] = nir_src_for_ssa(value);
+   if (addr_format_is_global(addr_format)) {
+      store->src[1] = nir_src_for_ssa(addr_to_global(b, addr, addr_format));
+   } else if (addr_format_is_offset(addr_format)) {
+      assert(addr->num_components == 1);
+      store->src[1] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   } else {
+      store->src[1] = nir_src_for_ssa(addr_to_index(b, addr, addr_format));
+      store->src[2] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   }
+
+   nir_intrinsic_set_write_mask(store, write_mask);
+
+   if (nir_intrinsic_has_access(store))
+      nir_intrinsic_set_access(store, nir_intrinsic_access(intrin));
+
+   /* TODO: We should try and provide a better alignment.  For OpenCL, we need
+    * to plumb the alignment through from SPIR-V when we have one.
+    */
+   nir_intrinsic_set_align(store, value->bit_size / 8, 0);
+
+   assert(value->num_components == 1 ||
+          value->num_components == intrin->num_components);
+   store->num_components = value->num_components;
+
+   assert(value->bit_size % 8 == 0);
+
+   if (addr_format_needs_bounds_check(addr_format)) {
+      const unsigned store_size = (value->bit_size / 8) * store->num_components;
+      nir_push_if(b, addr_is_in_bounds(b, addr, addr_format, store_size));
+
+      nir_builder_instr_insert(b, &store->instr);
+
+      nir_pop_if(b, NULL);
+   } else {
+      nir_builder_instr_insert(b, &store->instr);
+   }
+}
+
+static nir_ssa_def *
+build_explicit_io_atomic(nir_builder *b, nir_intrinsic_instr *intrin,
+                         nir_ssa_def *addr, nir_address_format addr_format)
+{
+   nir_variable_mode mode = nir_src_as_deref(intrin->src[0])->mode;
+   const unsigned num_data_srcs =
+      nir_intrinsic_infos[intrin->intrinsic].num_srcs - 1;
+
+   nir_intrinsic_op op;
+   switch (mode) {
+   case nir_var_mem_ssbo:
+      if (addr_format_is_global(addr_format))
+         op = global_atomic_for_deref(intrin->intrinsic);
+      else
+         op = ssbo_atomic_for_deref(intrin->intrinsic);
+      break;
+   case nir_var_mem_global:
+      assert(addr_format_is_global(addr_format));
+      op = global_atomic_for_deref(intrin->intrinsic);
+      break;
+   case nir_var_mem_shared:
+      assert(addr_format_is_offset(addr_format));
+      op = shared_atomic_for_deref(intrin->intrinsic);
+      break;
+   default:
+      unreachable("Unsupported explicit IO variable mode");
+   }
+
+   nir_intrinsic_instr *atomic = nir_intrinsic_instr_create(b->shader, op);
+
+   unsigned src = 0;
+   if (addr_format_is_global(addr_format)) {
+      atomic->src[src++] = nir_src_for_ssa(addr_to_global(b, addr, addr_format));
+   } else if (addr_format_is_offset(addr_format)) {
+      assert(addr->num_components == 1);
+      atomic->src[src++] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   } else {
+      atomic->src[src++] = nir_src_for_ssa(addr_to_index(b, addr, addr_format));
+      atomic->src[src++] = nir_src_for_ssa(addr_to_offset(b, addr, addr_format));
+   }
+   for (unsigned i = 0; i < num_data_srcs; i++) {
+      atomic->src[src++] = nir_src_for_ssa(intrin->src[1 + i].ssa);
+   }
+
+   /* Global atomics don't have access flags because they assume that the
+    * address may be non-uniform.
+    */
+   if (nir_intrinsic_has_access(atomic))
+      nir_intrinsic_set_access(atomic, nir_intrinsic_access(intrin));
+
+   assert(intrin->dest.ssa.num_components == 1);
+   nir_ssa_dest_init(&atomic->instr, &atomic->dest,
+                     1, intrin->dest.ssa.bit_size, intrin->dest.ssa.name);
+
+   assert(atomic->dest.ssa.bit_size % 8 == 0);
+
+   if (addr_format_needs_bounds_check(addr_format)) {
+      const unsigned atomic_size = atomic->dest.ssa.bit_size / 8;
+      nir_push_if(b, addr_is_in_bounds(b, addr, addr_format, atomic_size));
+
+      nir_builder_instr_insert(b, &atomic->instr);
+
+      nir_pop_if(b, NULL);
+      return nir_if_phi(b, &atomic->dest.ssa,
+                           nir_ssa_undef(b, 1, atomic->dest.ssa.bit_size));
+   } else {
+      nir_builder_instr_insert(b, &atomic->instr);
+      return &atomic->dest.ssa;
+   }
+}
+
+nir_ssa_def *
+nir_explicit_io_address_from_deref(nir_builder *b, nir_deref_instr *deref,
+                                   nir_ssa_def *base_addr,
+                                   nir_address_format addr_format)
+{
+   assert(deref->dest.is_ssa);
+   switch (deref->deref_type) {
+   case nir_deref_type_var:
+      return build_addr_for_var(b, deref->var, addr_format);
+
+   case nir_deref_type_array: {
+      nir_deref_instr *parent = nir_deref_instr_parent(deref);
+
+      unsigned stride = glsl_get_explicit_stride(parent->type);
+      if ((glsl_type_is_matrix(parent->type) &&
+           glsl_matrix_type_is_row_major(parent->type)) ||
+          (glsl_type_is_vector(parent->type) && stride == 0))
+         stride = type_scalar_size_bytes(parent->type);
+
+      assert(stride > 0);
+
+      nir_ssa_def *index = nir_ssa_for_src(b, deref->arr.index, 1);
+      index = nir_i2i(b, index, addr_get_offset_bit_size(base_addr, addr_format));
+      return build_addr_iadd(b, base_addr, addr_format,
+                                nir_amul_imm(b, index, stride));
+   }
+
+   case nir_deref_type_ptr_as_array: {
+      nir_ssa_def *index = nir_ssa_for_src(b, deref->arr.index, 1);
+      index = nir_i2i(b, index, addr_get_offset_bit_size(base_addr, addr_format));
+      unsigned stride = nir_deref_instr_ptr_as_array_stride(deref);
+      return build_addr_iadd(b, base_addr, addr_format,
+                                nir_amul_imm(b, index, stride));
+   }
+
+   case nir_deref_type_array_wildcard:
+      unreachable("Wildcards should be lowered by now");
+      break;
+
+   case nir_deref_type_struct: {
+      nir_deref_instr *parent = nir_deref_instr_parent(deref);
+      int offset = glsl_get_struct_field_offset(parent->type,
+                                                deref->strct.index);
+      assert(offset >= 0);
+      return build_addr_iadd_imm(b, base_addr, addr_format, offset);
+   }
+
+   case nir_deref_type_cast:
+      /* Nothing to do here */
+      return base_addr;
+   }
+
+   unreachable("Invalid NIR deref type");
+}
+
+void
+nir_lower_explicit_io_instr(nir_builder *b,
+                            nir_intrinsic_instr *intrin,
+                            nir_ssa_def *addr,
+                            nir_address_format addr_format)
+{
+   b->cursor = nir_after_instr(&intrin->instr);
+
+   nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+   unsigned vec_stride = glsl_get_explicit_stride(deref->type);
+   unsigned scalar_size = type_scalar_size_bytes(deref->type);
+   assert(vec_stride == 0 || glsl_type_is_vector(deref->type));
+   assert(vec_stride == 0 || vec_stride >= scalar_size);
+
+   if (intrin->intrinsic == nir_intrinsic_load_deref) {
+      nir_ssa_def *value;
+      if (vec_stride > scalar_size) {
+         nir_ssa_def *comps[4] = { NULL, };
+         for (unsigned i = 0; i < intrin->num_components; i++) {
+            nir_ssa_def *comp_addr = build_addr_iadd_imm(b, addr, addr_format,
+                                                         vec_stride * i);
+            comps[i] = build_explicit_io_load(b, intrin, comp_addr,
+                                              addr_format, 1);
+         }
+         value = nir_vec(b, comps, intrin->num_components);
+      } else {
+         value = build_explicit_io_load(b, intrin, addr, addr_format,
+                                        intrin->num_components);
+      }
+      nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(value));
+   } else if (intrin->intrinsic == nir_intrinsic_store_deref) {
+      assert(intrin->src[1].is_ssa);
+      nir_ssa_def *value = intrin->src[1].ssa;
+      nir_component_mask_t write_mask = nir_intrinsic_write_mask(intrin);
+      if (vec_stride > scalar_size) {
+         for (unsigned i = 0; i < intrin->num_components; i++) {
+            if (!(write_mask & (1 << i)))
+               continue;
+
+            nir_ssa_def *comp_addr = build_addr_iadd_imm(b, addr, addr_format,
+                                                         vec_stride * i);
+            build_explicit_io_store(b, intrin, comp_addr, addr_format,
+                                    nir_channel(b, value, i), 1);
+         }
+      } else {
+         build_explicit_io_store(b, intrin, addr, addr_format,
+                                 value, write_mask);
+      }
+   } else {
+      nir_ssa_def *value =
+         build_explicit_io_atomic(b, intrin, addr, addr_format);
+      nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(value));
+   }
+
+   nir_instr_remove(&intrin->instr);
+}
+
+static void
+lower_explicit_io_deref(nir_builder *b, nir_deref_instr *deref,
+                        nir_address_format addr_format)
+{
+   /* Just delete the deref if it's not used.  We can't use
+    * nir_deref_instr_remove_if_unused here because it may remove more than
+    * one deref which could break our list walking since we walk the list
+    * backwards.
+    */
+   assert(list_is_empty(&deref->dest.ssa.if_uses));
+   if (list_is_empty(&deref->dest.ssa.uses)) {
+      nir_instr_remove(&deref->instr);
+      return;
+   }
+
+   b->cursor = nir_after_instr(&deref->instr);
+
+   nir_ssa_def *base_addr = NULL;
+   if (deref->deref_type != nir_deref_type_var) {
+      assert(deref->parent.is_ssa);
+      base_addr = deref->parent.ssa;
+   }
+
+   nir_ssa_def *addr = nir_explicit_io_address_from_deref(b, deref, base_addr,
+                                                          addr_format);
+
+   nir_instr_remove(&deref->instr);
+   nir_ssa_def_rewrite_uses(&deref->dest.ssa, nir_src_for_ssa(addr));
+}
+
+static void
+lower_explicit_io_access(nir_builder *b, nir_intrinsic_instr *intrin,
+                         nir_address_format addr_format)
+{
+   assert(intrin->src[0].is_ssa);
+   nir_lower_explicit_io_instr(b, intrin, intrin->src[0].ssa, addr_format);
+}
+
+static void
+lower_explicit_io_array_length(nir_builder *b, nir_intrinsic_instr *intrin,
+                               nir_address_format addr_format)
+{
+   b->cursor = nir_after_instr(&intrin->instr);
+
+   nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+
+   assert(glsl_type_is_array(deref->type));
+   assert(glsl_get_length(deref->type) == 0);
+   unsigned stride = glsl_get_explicit_stride(deref->type);
+   assert(stride > 0);
+
+   nir_ssa_def *addr = &deref->dest.ssa;
+   nir_ssa_def *index = addr_to_index(b, addr, addr_format);
+   nir_ssa_def *offset = addr_to_offset(b, addr, addr_format);
+
+   nir_intrinsic_instr *bsize =
+      nir_intrinsic_instr_create(b->shader, nir_intrinsic_get_buffer_size);
+   bsize->src[0] = nir_src_for_ssa(index);
+   nir_ssa_dest_init(&bsize->instr, &bsize->dest, 1, 32, NULL);
+   nir_builder_instr_insert(b, &bsize->instr);
+
+   nir_ssa_def *arr_size =
+      nir_idiv(b, nir_isub(b, &bsize->dest.ssa, offset),
+                  nir_imm_int(b, stride));
+
+   nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(arr_size));
+   nir_instr_remove(&intrin->instr);
+}
+
+static bool
+nir_lower_explicit_io_impl(nir_function_impl *impl, nir_variable_mode modes,
+                           nir_address_format addr_format)
+{
+   bool progress = false;
+
+   nir_builder b;
+   nir_builder_init(&b, impl);
+
+   /* Walk in reverse order so that we can see the full deref chain when we
+    * lower the access operations.  We lower them assuming that the derefs
+    * will be turned into address calculations later.
+    */
+   nir_foreach_block_reverse(block, impl) {
+      nir_foreach_instr_reverse_safe(instr, block) {
+         switch (instr->type) {
+         case nir_instr_type_deref: {
+            nir_deref_instr *deref = nir_instr_as_deref(instr);
+            if (deref->mode & modes) {
+               lower_explicit_io_deref(&b, deref, addr_format);
+               progress = true;
+            }
+            break;
+         }
+
+         case nir_instr_type_intrinsic: {
+            nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+            switch (intrin->intrinsic) {
+            case nir_intrinsic_load_deref:
+            case nir_intrinsic_store_deref:
+            case nir_intrinsic_deref_atomic_add:
+            case nir_intrinsic_deref_atomic_imin:
+            case nir_intrinsic_deref_atomic_umin:
+            case nir_intrinsic_deref_atomic_imax:
+            case nir_intrinsic_deref_atomic_umax:
+            case nir_intrinsic_deref_atomic_and:
+            case nir_intrinsic_deref_atomic_or:
+            case nir_intrinsic_deref_atomic_xor:
+            case nir_intrinsic_deref_atomic_exchange:
+            case nir_intrinsic_deref_atomic_comp_swap:
+            case nir_intrinsic_deref_atomic_fadd:
+            case nir_intrinsic_deref_atomic_fmin:
+            case nir_intrinsic_deref_atomic_fmax:
+            case nir_intrinsic_deref_atomic_fcomp_swap: {
+               nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+               if (deref->mode & modes) {
+                  lower_explicit_io_access(&b, intrin, addr_format);
+                  progress = true;
+               }
+               break;
+            }
+
+            case nir_intrinsic_deref_buffer_array_length: {
+               nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
+               if (deref->mode & modes) {
+                  lower_explicit_io_array_length(&b, intrin, addr_format);
+                  progress = true;
+               }
+               break;
+            }
+
+            default:
+               break;
+            }
+            break;
+         }
+
+         default:
+            /* Nothing to do */
+            break;
+         }
+      }
+   }
+
+   if (progress) {
+      nir_metadata_preserve(impl, nir_metadata_block_index |
+                                  nir_metadata_dominance);
+   }
+
+   return progress;
+}
+
+/** Lower explicitly laid out I/O access to byte offset/address intrinsics
+ *
+ * This pass is intended to be used for any I/O which touches memory external
+ * to the shader or which is directly visible to the client.  It requires that
+ * all data types in the given modes have a explicit stride/offset decorations
+ * to tell it exactly how to calculate the offset/address for the given load,
+ * store, or atomic operation.  If the offset/stride information does not come
+ * from the client explicitly (as with shared variables in GL or Vulkan),
+ * nir_lower_vars_to_explicit_types() can be used to add them.
+ *
+ * Unlike nir_lower_io, this pass is fully capable of handling incomplete
+ * pointer chains which may contain cast derefs.  It does so by walking the
+ * deref chain backwards and simply replacing each deref, one at a time, with
+ * the appropriate address calculation.  The pass takes a nir_address_format
+ * parameter which describes how the offset or address is to be represented
+ * during calculations.  By ensuring that the address is always in a
+ * consistent format, pointers can safely be conjured from thin air by the
+ * driver, stored to variables, passed through phis, etc.
+ *
+ * The one exception to the simple algorithm described above is for handling
+ * row-major matrices in which case we may look down one additional level of
+ * the deref chain.
+ */
+bool
+nir_lower_explicit_io(nir_shader *shader, nir_variable_mode modes,
+                      nir_address_format addr_format)
+{
+   bool progress = false;
+
+   nir_foreach_function(function, shader) {
+      if (function->impl &&
+          nir_lower_explicit_io_impl(function->impl, modes, addr_format))
+         progress = true;
+   }
+
+   return progress;
+}
+
+static bool
+nir_lower_vars_to_explicit_types_impl(nir_function_impl *impl,
+                                      nir_variable_mode modes,
+                                      glsl_type_size_align_func type_info)
+{
+   bool progress = false;
+
+   nir_foreach_block(block, impl) {
+      nir_foreach_instr(instr, block) {
+         if (instr->type != nir_instr_type_deref)
+            continue;
+
+         nir_deref_instr *deref = nir_instr_as_deref(instr);
+         if (!(deref->mode & modes))
+            continue;
+
+         unsigned size, alignment;
+         const struct glsl_type *new_type =
+            glsl_get_explicit_type_for_size_align(deref->type, type_info, &size, &alignment);
+         if (new_type != deref->type) {
+            progress = true;
+            deref->type = new_type;
+         }
+         if (deref->deref_type == nir_deref_type_cast) {
+            /* See also glsl_type::get_explicit_type_for_size_align() */
+            unsigned new_stride = align(size, alignment);
+            if (new_stride != deref->cast.ptr_stride) {
+               deref->cast.ptr_stride = new_stride;
+               progress = true;
+            }
+         }
+      }
+   }
+
+   if (progress) {
+      nir_metadata_preserve(impl, nir_metadata_block_index |
+                                  nir_metadata_dominance |
+                                  nir_metadata_live_ssa_defs |
+                                  nir_metadata_loop_analysis);
+   }
+
+   return progress;
+}
+
+static bool
+lower_vars_to_explicit(nir_shader *shader,
+                       struct exec_list *vars, nir_variable_mode mode,
+                       glsl_type_size_align_func type_info)
+{
+   bool progress = false;
+   unsigned offset;
+   switch (mode) {
+   case nir_var_function_temp:
+   case nir_var_shader_temp:
+      offset = shader->scratch_size;
+      break;
+   case nir_var_mem_shared:
+      offset = 0;
+      break;
+   default:
+      unreachable("Unsupported mode");
+   }
+   nir_foreach_variable_in_list(var, vars) {
+      if (var->data.mode != mode)
+         continue;
+
+      unsigned size, align;
+      const struct glsl_type *explicit_type =
+         glsl_get_explicit_type_for_size_align(var->type, type_info, &size, &align);
+
+      if (explicit_type != var->type) {
+         progress = true;
+         var->type = explicit_type;
+      }
+
+      var->data.driver_location = ALIGN_POT(offset, align);
+      offset = var->data.driver_location + size;
+   }
+
+   switch (mode) {
+   case nir_var_shader_temp:
+   case nir_var_function_temp:
+      shader->scratch_size = offset;
+      break;
+   case nir_var_mem_shared:
+      shader->info.cs.shared_size = offset;
+      shader->shared_size = offset;
+      break;
+   default:
+      unreachable("Unsupported mode");
+   }
+
+   return progress;
+}
+
+bool
+nir_lower_vars_to_explicit_types(nir_shader *shader,
+                                 nir_variable_mode modes,
+                                 glsl_type_size_align_func type_info)
+{
+   /* TODO: Situations which need to be handled to support more modes:
+    * - row-major matrices
+    * - compact shader inputs/outputs
+    * - interface types
+    */
+   ASSERTED nir_variable_mode supported = nir_var_mem_shared |
+      nir_var_shader_temp | nir_var_function_temp;
+   assert(!(modes & ~supported) && "unsupported");
+
+   bool progress = false;
+
+   if (modes & nir_var_mem_shared)
+      progress |= lower_vars_to_explicit(shader, &shader->variables, nir_var_mem_shared, type_info);
+   if (modes & nir_var_shader_temp)
+      progress |= lower_vars_to_explicit(shader, &shader->variables, nir_var_shader_temp, type_info);
+
+   nir_foreach_function(function, shader) {
+      if (function->impl) {
+         if (modes & nir_var_function_temp)
+            progress |= lower_vars_to_explicit(shader, &function->impl->locals, nir_var_function_temp, type_info);
+
+         progress |= nir_lower_vars_to_explicit_types_impl(function->impl, modes, type_info);
+      }
+   }
+
+   return progress;
+}
+
+/**
+ * Return the offset source for a load/store intrinsic.
+ */
+nir_src *
+nir_get_io_offset_src(nir_intrinsic_instr *instr)
+{
+   switch (instr->intrinsic) {
+   case nir_intrinsic_load_input:
+   case nir_intrinsic_load_output:
+   case nir_intrinsic_load_shared:
+   case nir_intrinsic_load_uniform:
+   case nir_intrinsic_load_global:
+   case nir_intrinsic_load_global_constant:
+   case nir_intrinsic_load_scratch:
+   case nir_intrinsic_load_fs_input_interp_deltas:
+   case nir_intrinsic_shared_atomic_add:
+   case nir_intrinsic_shared_atomic_and:
+   case nir_intrinsic_shared_atomic_comp_swap:
+   case nir_intrinsic_shared_atomic_exchange:
+   case nir_intrinsic_shared_atomic_fadd:
+   case nir_intrinsic_shared_atomic_fcomp_swap:
+   case nir_intrinsic_shared_atomic_fmax:
+   case nir_intrinsic_shared_atomic_fmin:
+   case nir_intrinsic_shared_atomic_imax:
+   case nir_intrinsic_shared_atomic_imin:
+   case nir_intrinsic_shared_atomic_or:
+   case nir_intrinsic_shared_atomic_umax:
+   case nir_intrinsic_shared_atomic_umin:
+   case nir_intrinsic_shared_atomic_xor:
+   case nir_intrinsic_global_atomic_add:
+   case nir_intrinsic_global_atomic_and:
+   case nir_intrinsic_global_atomic_comp_swap:
+   case nir_intrinsic_global_atomic_exchange:
+   case nir_intrinsic_global_atomic_fadd:
+   case nir_intrinsic_global_atomic_fcomp_swap:
+   case nir_intrinsic_global_atomic_fmax:
+   case nir_intrinsic_global_atomic_fmin:
+   case nir_intrinsic_global_atomic_imax:
+   case nir_intrinsic_global_atomic_imin:
+   case nir_intrinsic_global_atomic_or:
+   case nir_intrinsic_global_atomic_umax:
+   case nir_intrinsic_global_atomic_umin:
+   case nir_intrinsic_global_atomic_xor:
+      return &instr->src[0];
+   case nir_intrinsic_load_ubo:
+   case nir_intrinsic_load_ssbo:
+   case nir_intrinsic_load_input_vertex:
+   case nir_intrinsic_load_per_vertex_input:
+   case nir_intrinsic_load_per_vertex_output:
+   case nir_intrinsic_load_interpolated_input:
+   case nir_intrinsic_store_output:
+   case nir_intrinsic_store_shared:
+   case nir_intrinsic_store_global:
+   case nir_intrinsic_store_scratch:
+   case nir_intrinsic_ssbo_atomic_add:
+   case nir_intrinsic_ssbo_atomic_imin:
+   case nir_intrinsic_ssbo_atomic_umin:
+   case nir_intrinsic_ssbo_atomic_imax:
+   case nir_intrinsic_ssbo_atomic_umax:
+   case nir_intrinsic_ssbo_atomic_and:
+   case nir_intrinsic_ssbo_atomic_or:
+   case nir_intrinsic_ssbo_atomic_xor:
+   case nir_intrinsic_ssbo_atomic_exchange:
+   case nir_intrinsic_ssbo_atomic_comp_swap:
+   case nir_intrinsic_ssbo_atomic_fadd:
+   case nir_intrinsic_ssbo_atomic_fmin:
+   case nir_intrinsic_ssbo_atomic_fmax:
+   case nir_intrinsic_ssbo_atomic_fcomp_swap:
+      return &instr->src[1];
+   case nir_intrinsic_store_ssbo:
+   case nir_intrinsic_store_per_vertex_output:
+      return &instr->src[2];
+   default:
+      return NULL;
+   }
+}
+
+/**
+ * Return the vertex index source for a load/store per_vertex intrinsic.
+ */
+nir_src *
+nir_get_io_vertex_index_src(nir_intrinsic_instr *instr)
+{
+   switch (instr->intrinsic) {
+   case nir_intrinsic_load_per_vertex_input:
+   case nir_intrinsic_load_per_vertex_output:
+      return &instr->src[0];
+   case nir_intrinsic_store_per_vertex_output:
+      return &instr->src[1];
+   default:
+      return NULL;
+   }
+}
+
+/**
+ * Return the numeric constant that identify a NULL pointer for each address
+ * format.
+ */
+const nir_const_value *
+nir_address_format_null_value(nir_address_format addr_format)
+{
+   const static nir_const_value null_values[][NIR_MAX_VEC_COMPONENTS] = {
+      [nir_address_format_32bit_global] = {{0}},
+      [nir_address_format_64bit_global] = {{0}},
+      [nir_address_format_64bit_bounded_global] = {{0}},
+      [nir_address_format_32bit_index_offset] = {{.u32 = ~0}, {.u32 = ~0}},
+      [nir_address_format_32bit_index_offset_pack64] = {{.u64 = ~0ull}},
+      [nir_address_format_vec2_index_32bit_offset] = {{.u32 = ~0}, {.u32 = ~0}, {.u32 = ~0}},
+      [nir_address_format_32bit_offset] = {{.u32 = ~0}},
+      [nir_address_format_32bit_offset_as_64bit] = {{.u64 = ~0ull}},
+      [nir_address_format_logical] = {{.u32 = ~0}},
+   };
+
+   assert(addr_format < ARRAY_SIZE(null_values));
+   return null_values[addr_format];
+}
+
+nir_ssa_def *
+nir_build_addr_ieq(nir_builder *b, nir_ssa_def *addr0, nir_ssa_def *addr1,
+                   nir_address_format addr_format)
+{
+   switch (addr_format) {
+   case nir_address_format_32bit_global:
+   case nir_address_format_64bit_global:
+   case nir_address_format_64bit_bounded_global:
+   case nir_address_format_32bit_index_offset:
+   case nir_address_format_vec2_index_32bit_offset:
+   case nir_address_format_32bit_offset:
+      return nir_ball_iequal(b, addr0, addr1);
+
+   case nir_address_format_32bit_offset_as_64bit:
+      assert(addr0->num_components == 1 && addr1->num_components == 1);
+      return nir_ieq(b, nir_u2u32(b, addr0), nir_u2u32(b, addr1));
+
+   case nir_address_format_32bit_index_offset_pack64:
+      assert(addr0->num_components == 1 && addr1->num_components == 1);
+      return nir_ball_iequal(b, nir_unpack_64_2x32(b, addr0), nir_unpack_64_2x32(b, addr1));
+
+   case nir_address_format_logical:
+      unreachable("Unsupported address format");
+   }
+
+   unreachable("Invalid address format");
+}
+
+nir_ssa_def *
+nir_build_addr_isub(nir_builder *b, nir_ssa_def *addr0, nir_ssa_def *addr1,
+                    nir_address_format addr_format)
+{
+   switch (addr_format) {
+   case nir_address_format_32bit_global:
+   case nir_address_format_64bit_global:
+   case nir_address_format_32bit_offset:
+   case nir_address_format_32bit_index_offset_pack64:
+      assert(addr0->num_components == 1);
+      assert(addr1->num_components == 1);
+      return nir_isub(b, addr0, addr1);
+
+   case nir_address_format_32bit_offset_as_64bit:
+      assert(addr0->num_components == 1);
+      assert(addr1->num_components == 1);
+      return nir_u2u64(b, nir_isub(b, nir_u2u32(b, addr0), nir_u2u32(b, addr1)));
+
+   case nir_address_format_64bit_bounded_global:
+      return nir_isub(b, addr_to_global(b, addr0, addr_format),
+                         addr_to_global(b, addr1, addr_format));
+
+   case nir_address_format_32bit_index_offset:
+      assert(addr0->num_components == 2);
+      assert(addr1->num_components == 2);
+      /* Assume the same buffer index. */
+      return nir_isub(b, nir_channel(b, addr0, 1), nir_channel(b, addr1, 1));
+
+   case nir_address_format_vec2_index_32bit_offset:
+      assert(addr0->num_components == 3);
+      assert(addr1->num_components == 3);
+      /* Assume the same buffer index. */
+      return nir_isub(b, nir_channel(b, addr0, 2), nir_channel(b, addr1, 2));
+
+   case nir_address_format_logical:
+      unreachable("Unsupported address format");
+   }
+
+   unreachable("Invalid address format");
+}
+
+static bool
+is_input(nir_intrinsic_instr *intrin)
+{
+   return intrin->intrinsic == nir_intrinsic_load_input ||
+          intrin->intrinsic == nir_intrinsic_load_per_vertex_input ||
+          intrin->intrinsic == nir_intrinsic_load_interpolated_input ||
+          intrin->intrinsic == nir_intrinsic_load_fs_input_interp_deltas;
+}
+
+static bool
+is_output(nir_intrinsic_instr *intrin)
+{
+   return intrin->intrinsic == nir_intrinsic_load_output ||
+          intrin->intrinsic == nir_intrinsic_load_per_vertex_output ||
+          intrin->intrinsic == nir_intrinsic_store_output ||
+          intrin->intrinsic == nir_intrinsic_store_per_vertex_output;
+}
+
+static bool is_dual_slot(nir_intrinsic_instr *intrin)
+{
+   if (intrin->intrinsic == nir_intrinsic_store_output ||
+       intrin->intrinsic == nir_intrinsic_store_per_vertex_output) {
+      return nir_src_bit_size(intrin->src[0]) == 64 &&
+             nir_src_num_components(intrin->src[0]) >= 3;
+   }
+
+   return nir_dest_bit_size(intrin->dest) &&
+          nir_dest_num_components(intrin->dest) >= 3;
+}
+
+/**
+ * This pass adds constant offsets to instr->const_index[0] for input/output
+ * intrinsics, and resets the offset source to 0.  Non-constant offsets remain
+ * unchanged - since we don't know what part of a compound variable is
+ * accessed, we allocate storage for the entire thing. For drivers that use
+ * nir_lower_io_to_temporaries() before nir_lower_io(), this guarantees that
+ * the offset source will be 0, so that they don't have to add it in manually.
+ */
+
+static bool
+add_const_offset_to_base_block(nir_block *block, nir_builder *b,
+                               nir_variable_mode mode)
+{
+   bool progress = false;
+   nir_foreach_instr_safe(instr, block) {
+      if (instr->type != nir_instr_type_intrinsic)
+         continue;
+
+      nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
+
+      if ((mode == nir_var_shader_in && is_input(intrin)) ||
+          (mode == nir_var_shader_out && is_output(intrin))) {
+         nir_src *offset = nir_get_io_offset_src(intrin);
+
+         if (nir_src_is_const(*offset)) {
+            unsigned off = nir_src_as_uint(*offset);
+
+            nir_intrinsic_set_base(intrin, nir_intrinsic_base(intrin) + off);
+
+            nir_io_semantics sem = nir_intrinsic_io_semantics(intrin);
+            sem.location += off;
+            /* non-indirect indexing should reduce num_slots */
+            sem.num_slots = is_dual_slot(intrin) ? 2 : 1;
+            nir_intrinsic_set_io_semantics(intrin, sem);
+
+            b->cursor = nir_before_instr(&intrin->instr);
+            nir_instr_rewrite_src(&intrin->instr, offset,
+                                  nir_src_for_ssa(nir_imm_int(b, 0)));
+            progress = true;
+         }
+      }
+   }
+
+   return progress;
+}
+
+bool
+nir_io_add_const_offset_to_base(nir_shader *nir, nir_variable_mode mode)
+{
+   bool progress = false;
+
+   nir_foreach_function(f, nir) {
+      if (f->impl) {
+         nir_builder b;
+         nir_builder_init(&b, f->impl);
+         nir_foreach_block(block, f->impl) {
+            progress |= add_const_offset_to_base_block(block, &b, mode);
+         }
+      }
+   }
+
+   return progress;
+}
+