[Mesa-dev] [PATCH] glsl: fix shader_storage_blocks_write_access for SSBO block arrays (v2)

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

This fixes KHR-GL45.compute_shader.resources-max on radeonsi.

Fixes: 4e1e8f684bf "glsl: remember which SSBOs are not read-only and pass it to gallium"

v2: use is_interface_array, protect again assertion failures in u_bit_consecutive
---
 src/compiler/glsl/link_uniforms.cpp | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/compiler/glsl/link_uniforms.cpp b/src/compiler/glsl/link_uniforms.cpp
index ef124111991..aa96227a7e1 100644
--- a/src/compiler/glsl/link_uniforms.cpp
+++ b/src/compiler/glsl/link_uniforms.cpp
@@ -515,44 +515,60 @@ public:
       this->record_next_bindless_sampler = new string_to_uint_map;
       this->record_next_image = new string_to_uint_map;
       this->record_next_bindless_image = new string_to_uint_map;
 
       buffer_block_index = -1;
       if (var->is_in_buffer_block()) {
          struct gl_uniform_block *blks = var->is_in_shader_storage_block() ?
             prog->data->ShaderStorageBlocks : prog->data->UniformBlocks;
          unsigned num_blks = var->is_in_shader_storage_block() ?
             prog->data->NumShaderStorageBlocks : prog->data->NumUniformBlocks;
+         bool is_interface_array =
+            var->is_interface_instance() && var->type->is_array();
 
-         if (var->is_interface_instance() && var->type->is_array()) {
+         if (is_interface_array) {
             unsigned l = strlen(var->get_interface_type()->name);
 
             for (unsigned i = 0; i < num_blks; i++) {
                if (strncmp(var->get_interface_type()->name, blks[i].Name, l)
                    == 0 && blks[i].Name[l] == '[') {
                   buffer_block_index = i;
                   break;
                }
             }
          } else {
             for (unsigned i = 0; i < num_blks; i++) {
                if (strcmp(var->get_interface_type()->name, blks[i].Name) == 0) {
                   buffer_block_index = i;
                   break;
                }
             }
          }
          assert(buffer_block_index != -1);
 
          if (var->is_in_shader_storage_block() &&
-             !var->data.memory_read_only)
-            shader_storage_blocks_write_access |= 1 << buffer_block_index;
+             !var->data.memory_read_only) {
+            unsigned array_size = is_interface_array ?
+                                     var->type->array_size() : 1;
+
+            STATIC_ASSERT(MAX_SHADER_STORAGE_BUFFERS <= 32);
+
+            /* Shaders that use too many SSBOs will fail to compile, which
+             * we don't care about.
+             *
+             * This is true for shaders that do not use too many SSBOs:
+             */
+            if (buffer_block_index + array_size <= 32) {
+               shader_storage_blocks_write_access |=
+                  u_bit_consecutive(buffer_block_index, array_size);
+            }
+         }
 
          /* Uniform blocks that were specified with an instance name must be
           * handled a little bit differently.  The name of the variable is the
           * name used to reference the uniform block instead of being the name
           * of a variable within the block.  Therefore, searching for the name
           * within the block will fail.
           */
          if (var->is_interface_instance()) {
             ubo_byte_offset = 0;
             process(var->get_interface_type(),
-- 
2.17.1