GLSL 1.50 spec says: "If gl_FragCoord is redeclared in any fragment shader in a program, it must be redeclared in all the fragment shaders in that program that have a static use gl_FragCoord. All redeclarations of gl_FragCoord in all fragment shaders in a single program must have the same set of qualifiers."
This patch makes the glsl compiler to generate an error if we have a fragment shader defined with conflicting layout qualifier declarations for gl_FragCoord. For example: layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord; layout(pixel_center_integer) in vec4 gl_FragCoord; void main() { } V2: Some code refactoring for better readability. Add compiler error conditions for redeclarations like: layout(origin_upper_left) in vec4 gl_FragCoord; layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord; and in vec4 gl_FragCoord; layout(origin_upper_left, pixel_center_integer) in vec4 gl_FragCoord; Signed-off-by: Anuj Phogat <anuj.pho...@gmail.com> Cc: <mesa-sta...@lists.freedesktop.org> --- This series is also available at: https://github.com/aphogat/mesa.git, branch='review' src/glsl/ast_to_hir.cpp | 60 +++++++++++++++++++++++++++++++++++++++++ src/glsl/glsl_parser_extras.cpp | 5 ++++ src/glsl/glsl_parser_extras.h | 12 +++++++++ 3 files changed, 77 insertions(+) diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp index f06baeb..9fe3095 100644 --- a/src/glsl/ast_to_hir.cpp +++ b/src/glsl/ast_to_hir.cpp @@ -2295,6 +2295,36 @@ apply_image_qualifier_to_variable(const struct ast_type_qualifier *qual, } } +static inline const char* +get_layout_qualifier_string(bool origin_upper_left, bool pixel_center_integer) +{ + if (origin_upper_left && pixel_center_integer) + return "origin_upper_left, pixel_center_integer"; + else if (origin_upper_left) + return "origin_upper_left"; + else if (pixel_center_integer) + return "pixel_center_integer"; + else + return " "; +} + +static inline bool +is_conflicting_fragcoord_redeclaration(struct _mesa_glsl_parse_state *state, + const struct ast_type_qualifier *qual) +{ + bool conflicting_origin_upper_left = + (state->fs_origin_upper_left && !qual->flags.q.origin_upper_left) || + (!state->fs_origin_upper_left && qual->flags.q.origin_upper_left && + state->fs_redeclares_gl_fragcoord); + + bool conflicting_pixel_center_integer = + (state->fs_pixel_center_integer && !qual->flags.q.pixel_center_integer) || + (!state->fs_pixel_center_integer && qual->flags.q.pixel_center_integer && + state->fs_redeclares_gl_fragcoord); + + return (conflicting_origin_upper_left || conflicting_pixel_center_integer); +} + static void apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual, ir_variable *var, @@ -2459,6 +2489,36 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual, qual_string); } + if (strcmp(var->name, "gl_FragCoord") == 0) { + + /* Make sure all gl_FragCoord redeclarations specify the same layout + * qualifiers. + */ + if (is_conflicting_fragcoord_redeclaration(state, qual)) { + const char *const qual_string = + get_layout_qualifier_string(qual->flags.q.origin_upper_left, + qual->flags.q.pixel_center_integer); + + const char *const state_string = + get_layout_qualifier_string(state->fs_origin_upper_left, + state->fs_pixel_center_integer); + + _mesa_glsl_error(loc, state, + "gl_FragCoord redeclared with different layout " + "qualifiers (%s) and (%s) ", + state_string, + qual_string); + } + state->fs_origin_upper_left = qual->flags.q.origin_upper_left; + state->fs_pixel_center_integer = qual->flags.q.pixel_center_integer; + state->fs_redeclares_gl_fragcoord_with_no_layout_qualifiers = + !qual->flags.q.origin_upper_left && !qual->flags.q.pixel_center_integer; + state->fs_redeclares_gl_fragcoord = + state->fs_origin_upper_left || + state->fs_pixel_center_integer || + state->fs_redeclares_gl_fragcoord_with_no_layout_qualifiers; + } + if (qual->flags.q.explicit_location) { validate_explicit_location(qual, var, state, loc); } else if (qual->flags.q.explicit_index) { diff --git a/src/glsl/glsl_parser_extras.cpp b/src/glsl/glsl_parser_extras.cpp index d7f5202..fcbbf44 100644 --- a/src/glsl/glsl_parser_extras.cpp +++ b/src/glsl/glsl_parser_extras.cpp @@ -201,6 +201,11 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx, this->default_uniform_qualifier->flags.q.shared = 1; this->default_uniform_qualifier->flags.q.column_major = 1; + this->fs_redeclares_gl_fragcoord = false; + this->fs_origin_upper_left = false; + this->fs_pixel_center_integer = false; + this->fs_redeclares_gl_fragcoord_with_no_layout_qualifiers = false; + this->gs_input_prim_type_specified = false; this->gs_input_size = 0; this->in_qualifier = new(this) ast_type_qualifier(); diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h index 300d900..2017913 100644 --- a/src/glsl/glsl_parser_extras.h +++ b/src/glsl/glsl_parser_extras.h @@ -204,6 +204,18 @@ struct _mesa_glsl_parse_state { struct ast_type_qualifier *default_uniform_qualifier; /** + * Variables to track different cases if a fragment shader redeclares + * built-in variable gl_FragCoord. + * + * Note: These values are computed at ast_to_hir time rather than at parse + * time. + */ + bool fs_redeclares_gl_fragcoord; + bool fs_origin_upper_left; + bool fs_pixel_center_integer; + bool fs_redeclares_gl_fragcoord_with_no_layout_qualifiers; + + /** * True if a geometry shader input primitive type was specified using a * layout directive. * -- 1.8.3.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev