<div dir="ltr">On 27 October 2013 14:59, Ian Romanick <<a href="mailto:idr@freedesktop.org" target="_blank">idr@freedesktop.org</a>> wrote: <div class="gmail_extra"><div class="gmail_quote"> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">From: Ian Romanick <<a href="mailto:ian.d.romanick@intel.com">ian.d.romanick@intel.com</a>> Future patches will add some extra code to this path, and some of that code will want to exit from the explicit location code early. Signed-off-by: Ian Romanick <<a href="mailto:ian.d.romanick@intel.com">ian.d.romanick@intel.com</a>> --- src/glsl/ast_to_hir.cpp | 159 +++++++++++++++++++++++++----------------------- 1 file changed, 84 insertions(+), 75 deletions(-) diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp index 561d942..05539b8 100644 --- a/src/glsl/ast_to_hir.cpp +++ b/src/glsl/ast_to_hir.cpp @@ -2043,6 +2043,89 @@ interpret_interpolation_qualifier(const struct ast_type_qualifier *qual, static void +validate_explicit_location(const struct ast_type_qualifier *qual, + ir_variable *var, + struct _mesa_glsl_parse_state *state, + YYLTYPE *loc) +{ + const bool global_scope = (state->current_function == NULL); + bool fail = false; + const char *string = ""; + + /* In the vertex shader only shader inputs can be given explicit + * locations. + * + * In the fragment shader only shader outputs can be given explicit + * locations. + */ + switch (state->target) { + case vertex_shader: + if (!global_scope || (var->mode != ir_var_shader_in)) { + fail = true; + string = "input"; + } + break; + + case geometry_shader: + _mesa_glsl_error(loc, state, + "geometry shader variables cannot be given " + "explicit locations"); + break; </blockquote><div> </div><div>While you're at it (either in this patch or a separate patch) you might want to change this "break;" to a "return;". That way we won't end up trying to apply a bogus geometry shader location qualifier (which could might cause cascading errors). </div><div>Either way, though, this patch is: Reviewed-by: Paul Berry <<a href="mailto:stereotype441@gmail.com">stereotype441@gmail.com</a>> </div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> + + case fragment_shader: + if (!global_scope || (var->mode != ir_var_shader_out)) { + fail = true; + string = "output"; + } + break; + }; + + if (fail) { + _mesa_glsl_error(loc, state, + "only %s shader %s variables can be given an " + "explicit location", + _mesa_glsl_shader_target_name(state->target), + string); + } else { + var->explicit_location = true; + + /* This bit of silliness is needed because invalid explicit locations + * are supposed to be flagged during linking. Small negative values + * biased by VERT_ATTRIB_GENERIC0 or FRAG_RESULT_DATA0 could alias + * built-in values (e.g., -16+VERT_ATTRIB_GENERIC0 = VERT_ATTRIB_POS). + * The linker needs to be able to differentiate these cases. This + * ensures that negative values stay negative. + */ + if (qual->location >= 0) { + var->location = (state->target == vertex_shader) + ? (qual->location + VERT_ATTRIB_GENERIC0) + : (qual->location + FRAG_RESULT_DATA0); + } else { + var->location = qual->location; + } + + if (qual->flags.q.explicit_index) { + /* From the GLSL 4.30 specification, section 4.4.2 (Output + * Layout Qualifiers): + * + * "It is also a compile-time error if a fragment shader + * sets a layout index to less than 0 or greater than 1." + * + * Older specifications don't mandate a behavior; we take + * this as a clarification and always generate the error. + */ + if (qual->index < 0 || qual->index > 1) { + _mesa_glsl_error(loc, state, + "explicit index may only be 0 or 1"); + } else { + var->explicit_index = true; + var->index = qual->index; + } + } + } +} + +static void apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual, ir_variable *var, struct _mesa_glsl_parse_state *state, @@ -2194,81 +2277,7 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual, } if (qual->flags.q.explicit_location) { - const bool global_scope = (state->current_function == NULL); - bool fail = false; - const char *string = ""; - - /* In the vertex shader only shader inputs can be given explicit - * locations. - * - * In the fragment shader only shader outputs can be given explicit - * locations. - */ - switch (state->target) { - case vertex_shader: - if (!global_scope || (var->mode != ir_var_shader_in)) { - fail = true; - string = "input"; - } - break; - - case geometry_shader: - _mesa_glsl_error(loc, state, - "geometry shader variables cannot be given " - "explicit locations"); - break; - - case fragment_shader: - if (!global_scope || (var->mode != ir_var_shader_out)) { - fail = true; - string = "output"; - } - break; - }; - - if (fail) { - _mesa_glsl_error(loc, state, - "only %s shader %s variables can be given an " - "explicit location", - _mesa_glsl_shader_target_name(state->target), - string); - } else { - var->explicit_location = true; - - /* This bit of silliness is needed because invalid explicit locations - * are supposed to be flagged during linking. Small negative values - * biased by VERT_ATTRIB_GENERIC0 or FRAG_RESULT_DATA0 could alias - * built-in values (e.g., -16+VERT_ATTRIB_GENERIC0 = VERT_ATTRIB_POS). - * The linker needs to be able to differentiate these cases. This - * ensures that negative values stay negative. - */ - if (qual->location >= 0) { - var->location = (state->target == vertex_shader) - ? (qual->location + VERT_ATTRIB_GENERIC0) - : (qual->location + FRAG_RESULT_DATA0); - } else { - var->location = qual->location; - } - - if (qual->flags.q.explicit_index) { - /* From the GLSL 4.30 specification, section 4.4.2 (Output - * Layout Qualifiers): - * - * "It is also a compile-time error if a fragment shader - * sets a layout index to less than 0 or greater than 1." - * - * Older specifications don't mandate a behavior; we take - * this as a clarification and always generate the error. - */ - if (qual->index < 0 || qual->index > 1) { - _mesa_glsl_error(loc, state, - "explicit index may only be 0 or 1"); - } else { - var->explicit_index = true; - var->index = qual->index; - } - } - } + validate_explicit_location(qual, var, state, loc); } else if (qual->flags.q.explicit_index) { _mesa_glsl_error(loc, state, "explicit index requires explicit location"); -- 1.8.1.4 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/mesa-dev" target="_blank">http://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div> </div></div>