v2: - ES version check (Tapani Pälli) v3/v4: - compare varying slot locations rather than names (Ilia Mirkin)
The conditions for which certain built-in special variables can be declared invariant were not being checked. GLSL ES 1.00 specification, Section "Invariance and linkage" says: For the built-in special variables, gl_FragCoord can only be declared invariant if and only if gl_Position is declared invariant. Similarly gl_PointCoord can only be declared invariant if and only if gl_PointSize is declared invariant. It is an error to declare gl_FrontFacing as invariant. This fixes the following piglit tests in spec/glsl-es-1.00/linker: glsl-fcoord-invariant glsl-fface-invariant glsl-pcoord-invariant Signed-off-by: Lars Hamre <cheme...@gmail.com> --- NOTE: Someone with access will need to commit this after the review process src/compiler/glsl/link_varyings.cpp | 39 +++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp index 34c8906..755000e 100644 --- a/src/compiler/glsl/link_varyings.cpp +++ b/src/compiler/glsl/link_varyings.cpp @@ -336,6 +336,9 @@ cross_validate_outputs_to_inputs(struct gl_shader_program *prog, ir_variable *explicit_locations[MAX_VARYINGS_INCL_PATCH][4] = { {NULL, NULL} }; + bool is_gl_position_invariant = false; + bool is_gl_point_size_invariant = false; + /* Find all shader outputs in the "producer" stage. */ foreach_in_list(ir_instruction, node, producer->ir) { @@ -344,6 +347,13 @@ cross_validate_outputs_to_inputs(struct gl_shader_program *prog, if (var == NULL || var->data.mode != ir_var_shader_out) continue; + if (prog->IsES && prog->Version < 300) { + if (var->data.location == VARYING_SLOT_POS) + is_gl_position_invariant = var->data.invariant; + if (var->data.location == VARYING_SLOT_PSIZ) + is_gl_point_size_invariant = var->data.invariant; + } + if (!var->data.explicit_location || var->data.location < VARYING_SLOT_VAR0) parameters.add_variable(var); @@ -430,6 +440,35 @@ cross_validate_outputs_to_inputs(struct gl_shader_program *prog, if (input == NULL || input->data.mode != ir_var_shader_in) continue; + /* + * GLSL ES 1.00 specification, Section "Invariance and linkage" says: + * + * "For the built-in special variables, gl_FragCoord can + * only be declared invariant if and only if gl_Position is + * declared invariant. Similarly gl_PointCoord can only be + * declared invariant if and only if gl_PointSize is declared + * invariant. It is an error to declare gl_FrontFacing as invariant." + */ + if (prog->IsES && prog->Version < 300 && input->data.invariant) { + if (input->data.location == VARYING_SLOT_FACE) { + linker_error(prog, + "gl_FrontFacing cannot be declared invariant"); + return; + } else if (!is_gl_position_invariant && + input->data.location == VARYING_SLOT_POS) { + linker_error(prog, + "gl_FragCoord cannot be declared invariant " + "unless gl_Position is also invariant"); + return; + } else if (!is_gl_point_size_invariant && + input->data.location == VARYING_SLOT_PNTC) { + linker_error(prog, + "gl_PointCoord cannot be declared invariant " + "unless gl_PointSize is also invariant"); + return; + } + } + if (strcmp(input->name, "gl_Color") == 0 && input->data.used) { const ir_variable *const front_color = parameters.get_variable("gl_FrontColor"); -- 2.5.5 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev