On Monday, October 12, 2015 02:55:32 PM Kenneth Graunke wrote:
> +void
> +fs_visitor::emit_gs_input_load(const fs_reg &dst,
> + const nir_src &vertex_src,
> + unsigned input_offset,
> + unsigned num_components)
> +{
> + const brw_vue_prog_data *vue_prog_data = (const brw_vue_prog_data *)
> prog_data;
> + const unsigned vertex = nir_src_as_const_value(vertex_src)->u[0];
> +
> + const unsigned array_stride = vue_prog_data->urb_read_length * 8;
> +
> + const bool pushed = 4 * input_offset < array_stride;
> +
> + if (input_offset == 0) {
> + /* This is the VUE header, containing VARYING_SLOT_LAYER [.y],
> + * VARYING_SLOT_VIEWPORT [.z], and VARYING_SLOT_PSIZ [.w].
> + * Only gl_PointSize is available as a GS input, so they must
> + * be asking for that input.
> + */
> + if (pushed) {
> + bld.MOV(dst, fs_reg(ATTR, array_stride * vertex + 3, dst.type));
> + } else {
> + fs_reg tmp = bld.vgrf(dst.type, 4);
> + fs_inst *inst = bld.emit(SHADER_OPCODE_URB_READ_SIMD8, tmp,
> + fs_reg(vertex), fs_reg(0));
> + inst->regs_written = 4;
> + bld.MOV(dst, offset(tmp, bld, 3));
> + }
> + } else {
> + if (pushed) {
> + int index = vertex * array_stride + 4 * input_offset;
> + for (unsigned i = 0; i < num_components; i++) {
> + bld.MOV(offset(dst, bld, i), fs_reg(ATTR, index + i, dst.type));
> + }
> + } else {
> + fs_inst *inst = bld.emit(SHADER_OPCODE_URB_READ_SIMD8, dst,
> + fs_reg(vertex), fs_reg(input_offset));
> + inst->regs_written = num_components;
> + }
> + }
> +}
> +Kristian pointed out that for instanced geometry shaders, the input VUE handles are packed into a single register, rather than in 6 separate registers. So, this will probably not work out for ARB_gpu_shader5 GS instancing. I don't remember failing any Piglit tests in that area, but I should make sure this works. It doesn't necessarily need to block this landing, as this support is still hidden behind an environment variable and most of it is still good. --Ken
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
