From 0822517936d473f4889b07606e131e1dc3199644 Mon Sep 17 00:00:00 2001 From: Timothy Arceri Date: Wed, 24 Feb 2016 16:27:03 +1100 Subject: [PATCH] glsl: add helper to process xfb qualifiers during linking This function checks for any xfb_* qualifiers which will enable transform feedback mode and cause any API defined xfb varyings to be ignored. It also counts the number of varyings that have a xfb_offset qualifier and finally it calls the create_xfb_varying_names() helper to generate the names of varyings to be caputured. Reviewed-by: Dave Airlie --- src/compiler/glsl/link_varyings.cpp | 66 +++++++++++++++++++++++++++++ src/compiler/glsl/link_varyings.h | 5 +++ 2 files changed, 71 insertions(+) diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp index dae6fb216c7..b000012e429 100644 --- a/src/compiler/glsl/link_varyings.cpp +++ b/src/compiler/glsl/link_varyings.cpp @@ -106,6 +106,72 @@ create_xfb_varying_names(void *mem_ctx, const glsl_type *t, char **name, } } +bool +process_xfb_layout_qualifiers(void *mem_ctx, const gl_shader *sh, + unsigned *num_tfeedback_decls, + char ***varying_names) +{ + bool has_xfb_qualifiers = false; + + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *var = node->as_variable(); + if (!var || var->data.mode != ir_var_shader_out) + continue; + + /* From the ARB_enhanced_layouts spec: + * + * "Any shader making any static use (after preprocessing) of any of + * these *xfb_* qualifiers will cause the shader to be in a + * transform feedback capturing mode and hence responsible for + * describing the transform feedback setup. This mode will capture + * any output selected by *xfb_offset*, directly or indirectly, to + * a transform feedback buffer." + */ + if (var->data.explicit_xfb_buffer || var->data.explicit_xfb_stride) { + has_xfb_qualifiers = true; + } + + if (var->data.explicit_xfb_offset) { + *num_tfeedback_decls += var->type->varying_count(); + has_xfb_qualifiers = true; + } + } + + if (*num_tfeedback_decls == 0) + return has_xfb_qualifiers; + + unsigned i = 0; + *varying_names = ralloc_array(mem_ctx, char *, *num_tfeedback_decls); + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *var = node->as_variable(); + if (!var || var->data.mode != ir_var_shader_out) + continue; + + if (var->data.explicit_xfb_offset) { + char *name; + const glsl_type *type, *member_type; + + if (var->data.from_named_ifc_block) { + type = var->get_interface_type(); + /* Find the member type before it was altered by lowering */ + member_type = + type->fields.structure[type->field_index(var->name)].type; + name = ralloc_strdup(NULL, type->without_array()->name); + } else { + type = var->type; + member_type = NULL; + name = ralloc_strdup(NULL, var->name); + } + create_xfb_varying_names(mem_ctx, type, &name, strlen(name), &i, + var->name, member_type, varying_names); + ralloc_free(name); + } + } + + assert(i == *num_tfeedback_decls); + return has_xfb_qualifiers; +} + /** * Validate the types and qualifiers of an output from one stage against the * matching input to another stage. diff --git a/src/compiler/glsl/link_varyings.h b/src/compiler/glsl/link_varyings.h index b2812614ecc..8d504f6f0dc 100644 --- a/src/compiler/glsl/link_varyings.h +++ b/src/compiler/glsl/link_varyings.h @@ -268,6 +268,11 @@ parse_tfeedback_decls(struct gl_context *ctx, struct gl_shader_program *prog, const void *mem_ctx, unsigned num_names, char **varying_names, tfeedback_decl *decls); +bool +process_xfb_layout_qualifiers(void *mem_ctx, const gl_shader *sh, + unsigned *num_tfeedback_decls, + char ***varying_names); + void remove_unused_shader_inputs_and_outputs(bool is_separate_shader_object, gl_shader *sh, -- 2.30.2