[Mesa-dev] [RFC 2/2] mesa: Add {Num}UniformBlocks and {Num}ShaderStorageBlocks to gl_shader_program

[Iago Toral Quiroga]

These arrays provide backends with separate index spaces for UBOS and SSBOs.
---
 src/glsl/linker.cpp                 | 35 +++++++++++++++++++++++++++++++++++
 src/glsl/standalone_scaffolding.cpp |  9 +++++++++
 src/mesa/main/mtypes.h              |  6 ++++++
 3 files changed, 50 insertions(+)

diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index e6eba94..3da773d 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -4107,6 +4107,41 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
       }
    }
 
+   /* Split prog->BufferInterfaceBlocks into prog->UniformBlocks and
+    * prog->ShaderStorageBlocks, so that drivers that need separate index
+    * spaces for each set can have that.
+    */
+   unsigned num_ubo_blocks;
+   unsigned num_ssbo_blocks;
+   num_ubo_blocks = 0;
+   num_ssbo_blocks = 0;
+   for (unsigned i = 0; i < prog->NumBufferInterfaceBlocks; i++) {
+      if (prog->BufferInterfaceBlocks[i].IsShaderStorage)
+         num_ssbo_blocks++;
+      else
+         num_ubo_blocks++;
+   }
+
+   prog->UniformBlocks =
+      ralloc_array(mem_ctx, gl_uniform_block *, num_ubo_blocks);
+   prog->NumUniformBlocks = 0;
+
+   prog->ShaderStorageBlocks =
+      ralloc_array(mem_ctx, gl_uniform_block *, num_ssbo_blocks);
+   prog->NumShaderStorageBlocks = 0;
+
+   for (unsigned i = 0; i < prog->NumBufferInterfaceBlocks; i++) {
+      if (prog->BufferInterfaceBlocks[i].IsShaderStorage)
+         prog->ShaderStorageBlocks[prog->NumShaderStorageBlocks++] =
+            &prog->BufferInterfaceBlocks[i];
+      else
+         prog->UniformBlocks[prog->NumUniformBlocks++] =
+            &prog->BufferInterfaceBlocks[i];
+   }
+
+   assert(prog->NumUniformBlocks + prog->NumShaderStorageBlocks ==
+          prog->NumBufferInterfaceBlocks);
+
    /* FINISHME: Assign fragment shader output locations. */
 
 done:
diff --git a/src/glsl/standalone_scaffolding.cpp b/src/glsl/standalone_scaffolding.cpp
index 0c53589..658245f 100644
--- a/src/glsl/standalone_scaffolding.cpp
+++ b/src/glsl/standalone_scaffolding.cpp
@@ -102,6 +102,15 @@ _mesa_clear_shader_program_data(struct gl_shader_program *shProg)
    ralloc_free(shProg->BufferInterfaceBlocks);
    shProg->BufferInterfaceBlocks = NULL;
    shProg->NumBufferInterfaceBlocks = 0;
+
+   ralloc_free(shProg->UniformBlocks);
+   shProg->UniformBlocks = NULL;
+   shProg->NumUniformBlocks = 0;
+
+   ralloc_free(shProg->ShaderStorageBlocks);
+   shProg->ShaderStorageBlocks = NULL;
+   shProg->NumShaderStorageBlocks = 0;
+
    for (i = 0; i < MESA_SHADER_STAGES; i++) {
       ralloc_free(shProg->UniformBlockStageIndex[i]);
       shProg->UniformBlockStageIndex[i] = NULL;
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 347da14..2362f54 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2692,6 +2692,12 @@ struct gl_shader_program
    unsigned NumBufferInterfaceBlocks;
    struct gl_uniform_block *BufferInterfaceBlocks;
 
+   unsigned NumUniformBlocks;
+   struct gl_uniform_block **UniformBlocks;
+
+   unsigned NumShaderStorageBlocks;
+   struct gl_uniform_block **ShaderStorageBlocks;
+
    /**
     * Indices into the _LinkedShaders's UniformBlocks[] array for each stage
     * they're used in, or -1.
-- 
1.9.1