microsoft/compiler: Move kill-unused/undefined varying pass from spirv to common

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28535>

src/microsoft/compiler/dxil_nir.c

@@ -2842,3 +2842,140 @@ dxil_nir_lower_coherent_loads_and_stores(nir_shader *s)
                                      nir_metadata_block_index | nir_metadata_dominance | nir_metadata_loop_analysis,
                                      NULL);
 }
+
+static bool
+kill_undefined_varyings(struct nir_builder *b,
+                        nir_instr *instr,
+                        void *data)
+{
+   const nir_shader *prev_stage_nir = data;
+
+   if (instr->type != nir_instr_type_intrinsic)
+      return false;
+
+   nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
+
+   if (intr->intrinsic != nir_intrinsic_load_deref)
+      return false;
+
+   nir_variable *var = nir_intrinsic_get_var(intr, 0);
+   if (!var || var->data.mode != nir_var_shader_in)
+      return false;
+
+   /* Ignore most builtins for now, some of them get default values
+    * when not written from previous stages.
+    */
+   if (var->data.location < VARYING_SLOT_VAR0 &&
+       var->data.location != VARYING_SLOT_POS)
+      return false;
+
+   uint32_t loc = var->data.patch ?
+      var->data.location - VARYING_SLOT_PATCH0 : var->data.location;
+   uint64_t written = var->data.patch ?
+      prev_stage_nir->info.patch_outputs_written :
+      prev_stage_nir->info.outputs_written;
+   if (BITFIELD64_RANGE(loc, glsl_varying_count(var->type)) & written)
+      return false;
+
+   b->cursor = nir_after_instr(instr);
+   /* Note: zero is used instead of undef, because optimization is not run here, but is
+    * run later on. If we load an undef here, and that undef ends up being used to store
+    * to position later on, that can cause some or all of the components in that position
+    * write to be removed, which is problematic especially in the case of all components,
+    * since that would remove the store instruction, and would make it tricky to satisfy
+    * the DXIL requirements of writing all position components.
+    */
+   nir_def *zero = nir_imm_zero(b, intr->def.num_components,
+                                       intr->def.bit_size);
+   nir_def_rewrite_uses(&intr->def, zero);
+   nir_instr_remove(instr);
+   return true;
+}
+
+bool
+dxil_nir_kill_undefined_varyings(nir_shader *shader,
+                                 const nir_shader *prev_stage_shader)
+{
+   if (!nir_shader_instructions_pass(shader,
+                                     kill_undefined_varyings,
+                                     nir_metadata_dominance |
+                                     nir_metadata_block_index |
+                                     nir_metadata_loop_analysis,
+                                     (void *)prev_stage_shader))
+      return false;
+
+   nir_remove_dead_derefs(shader);
+   nir_remove_dead_variables(shader, nir_var_shader_in, NULL);
+   return true;
+}
+
+static bool
+kill_unused_outputs(struct nir_builder *b,
+                    nir_instr *instr,
+                    void *data)
+{
+   uint64_t kill_mask = *((uint64_t *)data);
+
+   if (instr->type != nir_instr_type_intrinsic)
+      return false;
+
+   nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
+
+   if (intr->intrinsic != nir_intrinsic_store_deref)
+      return false;
+
+   nir_variable *var = nir_intrinsic_get_var(intr, 0);
+   if (!var || var->data.mode != nir_var_shader_out)
+      return false;
+
+   unsigned loc = var->data.patch ?
+      var->data.location - VARYING_SLOT_PATCH0 :
+      var->data.location;
+   if (!(BITFIELD64_RANGE(loc, glsl_varying_count(var->type)) & kill_mask))
+      return false;
+
+   nir_instr_remove(instr);
+   return true;
+}
+
+bool
+dxil_nir_kill_unused_outputs(nir_shader *shader,
+                             const nir_shader *next_stage_shader)
+{
+   uint64_t kill_var_mask =
+      shader->info.outputs_written & ~next_stage_shader->info.inputs_read;
+   bool progress = false;
+
+   /* Don't kill buitin vars */
+   kill_var_mask &= BITFIELD64_MASK(MAX_VARYING) << VARYING_SLOT_VAR0;
+
+   if (nir_shader_instructions_pass(shader,
+                                    kill_unused_outputs,
+                                    nir_metadata_dominance |
+                                    nir_metadata_block_index |
+                                    nir_metadata_loop_analysis,
+                                    (void *)&kill_var_mask))
+      progress = true;
+
+   if (shader->info.stage == MESA_SHADER_TESS_CTRL) {
+      kill_var_mask =
+         (shader->info.patch_outputs_written |
+          shader->info.patch_outputs_read) &
+         ~next_stage_shader->info.patch_inputs_read;
+      if (nir_shader_instructions_pass(shader,
+                                       kill_unused_outputs,
+                                       nir_metadata_dominance |
+                                       nir_metadata_block_index |
+                                       nir_metadata_loop_analysis,
+                                       (void *)&kill_var_mask))
+         progress = true;
+   }
+
+   if (progress) {
+      nir_opt_dce(shader);
+      nir_remove_dead_derefs(shader);
+      nir_remove_dead_variables(shader, nir_var_shader_out, NULL);
+   }
+
+   return progress;
+}

src/microsoft/compiler/dxil_nir.h

@@ -89,6 +89,9 @@ bool dxil_nir_analyze_io_dependencies(struct dxil_module *mod, nir_shader *s);
 bool dxil_nir_guess_image_formats(nir_shader *s);
 bool dxil_nir_lower_coherent_loads_and_stores(nir_shader *s);
 
+bool dxil_nir_kill_undefined_varyings(nir_shader *shader, const nir_shader *prev_stage_shader);
+bool dxil_nir_kill_unused_outputs(nir_shader *shader, const nir_shader *next_stage_shader);
+
 #ifdef __cplusplus
 }
 #endif

src/microsoft/spirv_to_dxil/dxil_spirv_nir.c

@@ -551,143 +551,6 @@ dxil_spirv_nir_discard_point_size_var(nir_shader *shader)
    return true;
 }
 
-static bool
-kill_undefined_varyings(struct nir_builder *b,
-                        nir_instr *instr,
-                        void *data)
-{
-   const nir_shader *prev_stage_nir = data;
-
-   if (instr->type != nir_instr_type_intrinsic)
-      return false;
-
-   nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
-
-   if (intr->intrinsic != nir_intrinsic_load_deref)
-      return false;
-
-   nir_variable *var = nir_intrinsic_get_var(intr, 0);
-   if (!var || var->data.mode != nir_var_shader_in)
-      return false;
-
-   /* Ignore most builtins for now, some of them get default values
-    * when not written from previous stages.
-    */
-   if (var->data.location < VARYING_SLOT_VAR0 &&
-       var->data.location != VARYING_SLOT_POS)
-      return false;
-
-   uint32_t loc = var->data.patch ?
-                  var->data.location - VARYING_SLOT_PATCH0 : var->data.location;
-   uint64_t written = var->data.patch ?
-                      prev_stage_nir->info.patch_outputs_written :
-                      prev_stage_nir->info.outputs_written;
-   if (BITFIELD64_RANGE(loc, glsl_varying_count(var->type)) & written)
-      return false;
-
-   b->cursor = nir_after_instr(instr);
-   /* Note: zero is used instead of undef, because optimization is not run here, but is
-    * run later on. If we load an undef here, and that undef ends up being used to store
-    * to position later on, that can cause some or all of the components in that position
-    * write to be removed, which is problematic especially in the case of all components,
-    * since that would remove the store instruction, and would make it tricky to satisfy
-    * the DXIL requirements of writing all position components.
-    */
-   nir_def *zero = nir_imm_zero(b, intr->def.num_components,
-                                       intr->def.bit_size);
-   nir_def_rewrite_uses(&intr->def, zero);
-   nir_instr_remove(instr);
-   return true;
-}
-
-static bool
-dxil_spirv_nir_kill_undefined_varyings(nir_shader *shader,
-                                       const nir_shader *prev_stage_shader)
-{
-   if (!nir_shader_instructions_pass(shader,
-                                     kill_undefined_varyings,
-                                     nir_metadata_dominance |
-                                     nir_metadata_block_index |
-                                     nir_metadata_loop_analysis,
-                                     (void *)prev_stage_shader))
-      return false;
-
-   nir_remove_dead_derefs(shader);
-   nir_remove_dead_variables(shader, nir_var_shader_in, NULL);
-   return true;
-}
-
-static bool
-kill_unused_outputs(struct nir_builder *b,
-                    nir_instr *instr,
-                    void *data)
-{
-   uint64_t kill_mask = *((uint64_t *)data);
-
-   if (instr->type != nir_instr_type_intrinsic)
-      return false;
-
-   nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
-
-   if (intr->intrinsic != nir_intrinsic_store_deref)
-      return false;
-
-   nir_variable *var = nir_intrinsic_get_var(intr, 0);
-   if (!var || var->data.mode != nir_var_shader_out)
-      return false;
-
-   unsigned loc = var->data.patch ?
-                  var->data.location - VARYING_SLOT_PATCH0 :
-                  var->data.location;
-   if (!(BITFIELD64_RANGE(loc, glsl_varying_count(var->type)) & kill_mask))
-      return false;
-
-   nir_instr_remove(instr);
-   return true;
-}
-
-static bool
-dxil_spirv_nir_kill_unused_outputs(nir_shader *shader,
-                                   nir_shader *next_stage_shader)
-{
-   uint64_t kill_var_mask =
-      shader->info.outputs_written & ~next_stage_shader->info.inputs_read;
-   bool progress = false;
-
-   /* Don't kill buitin vars */
-   kill_var_mask &= BITFIELD64_MASK(MAX_VARYING) << VARYING_SLOT_VAR0;
-
-   if (nir_shader_instructions_pass(shader,
-                                    kill_unused_outputs,
-                                    nir_metadata_dominance |
-                                    nir_metadata_block_index |
-                                    nir_metadata_loop_analysis,
-                                    (void *)&kill_var_mask))
-      progress = true;
-
-   if (shader->info.stage == MESA_SHADER_TESS_CTRL) {
-      kill_var_mask =
-         (shader->info.patch_outputs_written |
-          shader->info.patch_outputs_read) &
-         ~next_stage_shader->info.patch_inputs_read;
-      if (nir_shader_instructions_pass(shader,
-                                       kill_unused_outputs,
-                                       nir_metadata_dominance |
-                                       nir_metadata_block_index |
-                                       nir_metadata_loop_analysis,
-                                       (void *)&kill_var_mask))
-         progress = true;
-   }
-
-   if (progress) {
-      nir_opt_dce(shader);
-      nir_remove_dead_derefs(shader);
-      nir_remove_dead_variables(shader, nir_var_shader_out, NULL);
-   }
-
-   return progress;
-}
-
 struct lower_pntc_data {
    const struct dxil_spirv_runtime_conf *conf;
    nir_variable *pntc;
@@ -906,8 +769,8 @@ dxil_spirv_nir_link(nir_shader *nir, nir_shader *prev_stage_nir,
          }
       }
 
-      NIR_PASS_V(nir, dxil_spirv_nir_kill_undefined_varyings, prev_stage_nir);
-      NIR_PASS_V(prev_stage_nir, dxil_spirv_nir_kill_unused_outputs, nir);
+      NIR_PASS_V(nir, dxil_nir_kill_undefined_varyings, prev_stage_nir);
+      NIR_PASS_V(prev_stage_nir, dxil_nir_kill_unused_outputs, nir);
 
       nir->info.inputs_read =
          dxil_reassign_driver_locations(nir, nir_var_shader_in,