/* * Copyright © 2013 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ /** * \file brw_vec4_gs.c * * State atom for client-programmable geometry shaders, and support code. */ #include "brw_gs.h" #include "brw_context.h" #include "brw_vec4_gs_visitor.h" #include "brw_state.h" #include "brw_ff_gs.h" bool brw_codegen_gs_prog(struct brw_context *brw, struct gl_shader_program *prog, struct brw_geometry_program *gp, struct brw_gs_prog_key *key) { struct brw_stage_state *stage_state = &brw->gs.base; struct brw_gs_compile c; memset(&c, 0, sizeof(c)); c.key = *key; c.gp = gp; c.prog_data.include_primitive_id = (gp->program.Base.InputsRead & VARYING_BIT_PRIMITIVE_ID) != 0; c.prog_data.invocations = gp->program.Invocations; /* Allocate the references to the uniforms that will end up in the * prog_data associated with the compiled program, and which will be freed * by the state cache. * * Note: param_count needs to be num_uniform_components * 4, since we add * padding around uniform values below vec4 size, so the worst case is that * every uniform is a float which gets padded to the size of a vec4. */ struct gl_shader *gs = prog->_LinkedShaders[MESA_SHADER_GEOMETRY]; int param_count = gs->num_uniform_components * 4; param_count += gs->NumImages * BRW_IMAGE_PARAM_SIZE; c.prog_data.base.base.param = rzalloc_array(NULL, const gl_constant_value *, param_count); c.prog_data.base.base.pull_param = rzalloc_array(NULL, const gl_constant_value *, param_count); c.prog_data.base.base.image_param = rzalloc_array(NULL, struct brw_image_param, gs->NumImages); c.prog_data.base.base.nr_params = param_count; c.prog_data.base.base.nr_image_params = gs->NumImages; if (brw->gen >= 8) { c.prog_data.static_vertex_count = !gp->program.Base.nir ? -1 : nir_gs_count_vertices(gp->program.Base.nir); } if (brw->gen >= 7) { if (gp->program.OutputType == GL_POINTS) { /* When the output type is points, the geometry shader may output data * to multiple streams, and EndPrimitive() has no effect. So we * configure the hardware to interpret the control data as stream ID. */ c.prog_data.control_data_format = GEN7_GS_CONTROL_DATA_FORMAT_GSCTL_SID; /* We only have to emit control bits if we are using streams */ if (prog->Geom.UsesStreams) c.control_data_bits_per_vertex = 2; else c.control_data_bits_per_vertex = 0; } else { /* When the output type is triangle_strip or line_strip, EndPrimitive() * may be used to terminate the current strip and start a new one * (similar to primitive restart), and outputting data to multiple * streams is not supported. So we configure the hardware to interpret * the control data as EndPrimitive information (a.k.a. "cut bits"). */ c.prog_data.control_data_format = GEN7_GS_CONTROL_DATA_FORMAT_GSCTL_CUT; /* We only need to output control data if the shader actually calls * EndPrimitive(). */ c.control_data_bits_per_vertex = gp->program.UsesEndPrimitive ? 1 : 0; } } else { /* There are no control data bits in gen6. */ c.control_data_bits_per_vertex = 0; /* If it is using transform feedback, enable it */ if (prog->TransformFeedback.NumVarying) c.prog_data.gen6_xfb_enabled = true; else c.prog_data.gen6_xfb_enabled = false; } c.control_data_header_size_bits = gp->program.VerticesOut * c.control_data_bits_per_vertex; /* 1 HWORD = 32 bytes = 256 bits */ c.prog_data.control_data_header_size_hwords = ALIGN(c.control_data_header_size_bits, 256) / 256; GLbitfield64 outputs_written = gp->program.Base.OutputsWritten; brw_compute_vue_map(brw->intelScreen->devinfo, &c.prog_data.base.vue_map, outputs_written, prog ? prog->SeparateShader : false); /* Compute the output vertex size. * * From the Ivy Bridge PRM, Vol2 Part1 7.2.1.1 STATE_GS - Output Vertex * Size (p168): * * [0,62] indicating [1,63] 16B units * * Specifies the size of each vertex stored in the GS output entry * (following any Control Header data) as a number of 128-bit units * (minus one). * * Programming Restrictions: The vertex size must be programmed as a * multiple of 32B units with the following exception: Rendering is * disabled (as per SOL stage state) and the vertex size output by the * GS thread is 16B. * * If rendering is enabled (as per SOL state) the vertex size must be * programmed as a multiple of 32B units. In other words, the only time * software can program a vertex size with an odd number of 16B units * is when rendering is disabled. * * Note: B=bytes in the above text. * * It doesn't seem worth the extra trouble to optimize the case where the * vertex size is 16B (especially since this would require special-casing * the GEN assembly that writes to the URB). So we just set the vertex * size to a multiple of 32B (2 vec4's) in all cases. * * The maximum output vertex size is 62*16 = 992 bytes (31 hwords). We * budget that as follows: * * 512 bytes for varyings (a varying component is 4 bytes and * gl_MaxGeometryOutputComponents = 128) * 16 bytes overhead for VARYING_SLOT_PSIZ (each varying slot is 16 * bytes) * 16 bytes overhead for gl_Position (we allocate it a slot in the VUE * even if it's not used) * 32 bytes overhead for gl_ClipDistance (we allocate it 2 VUE slots * whenever clip planes are enabled, even if the shader doesn't * write to gl_ClipDistance) * 16 bytes overhead since the VUE size must be a multiple of 32 bytes * (see below)--this causes up to 1 VUE slot to be wasted * 400 bytes available for varying packing overhead * * Worst-case varying packing overhead is 3/4 of a varying slot (12 bytes) * per interpolation type, so this is plenty. * */ unsigned output_vertex_size_bytes = c.prog_data.base.vue_map.num_slots * 16; assert(brw->gen == 6 || output_vertex_size_bytes <= GEN7_MAX_GS_OUTPUT_VERTEX_SIZE_BYTES); c.prog_data.output_vertex_size_hwords = ALIGN(output_vertex_size_bytes, 32) / 32; /* Compute URB entry size. The maximum allowed URB entry size is 32k. * That divides up as follows: * * 64 bytes for the control data header (cut indices or StreamID bits) * 4096 bytes for varyings (a varying component is 4 bytes and * gl_MaxGeometryTotalOutputComponents = 1024) * 4096 bytes overhead for VARYING_SLOT_PSIZ (each varying slot is 16 * bytes/vertex and gl_MaxGeometryOutputVertices is 256) * 4096 bytes overhead for gl_Position (we allocate it a slot in the VUE * even if it's not used) * 8192 bytes overhead for gl_ClipDistance (we allocate it 2 VUE slots * whenever clip planes are enabled, even if the shader doesn't * write to gl_ClipDistance) * 4096 bytes overhead since the VUE size must be a multiple of 32 * bytes (see above)--this causes up to 1 VUE slot to be wasted * 8128 bytes available for varying packing overhead * * Worst-case varying packing overhead is 3/4 of a varying slot per * interpolation type, which works out to 3072 bytes, so this would allow * us to accommodate 2 interpolation types without any danger of running * out of URB space. * * In practice, the risk of running out of URB space is very small, since * the above figures are all worst-case, and most of them scale with the * number of output vertices. So we'll just calculate the amount of space * we need, and if it's too large, fail to compile. * * The above is for gen7+ where we have a single URB entry that will hold * all the output. In gen6, we will have to allocate URB entries for every * vertex we emit, so our URB entries only need to be large enough to hold * a single vertex. Also, gen6 does not have a control data header. */ unsigned output_size_bytes; if (brw->gen >= 7) { output_size_bytes = c.prog_data.output_vertex_size_hwords * 32 * gp->program.VerticesOut; output_size_bytes += 32 * c.prog_data.control_data_header_size_hwords; } else { output_size_bytes = c.prog_data.output_vertex_size_hwords * 32; } /* Broadwell stores "Vertex Count" as a full 8 DWord (32 byte) URB output, * which comes before the control header. */ if (brw->gen >= 8) output_size_bytes += 32; assert(output_size_bytes >= 1); int max_output_size_bytes = GEN7_MAX_GS_URB_ENTRY_SIZE_BYTES; if (brw->gen == 6) max_output_size_bytes = GEN6_MAX_GS_URB_ENTRY_SIZE_BYTES; if (output_size_bytes > max_output_size_bytes) return false; /* URB entry sizes are stored as a multiple of 64 bytes in gen7+ and * a multiple of 128 bytes in gen6. */ if (brw->gen >= 7) c.prog_data.base.urb_entry_size = ALIGN(output_size_bytes, 64) / 64; else c.prog_data.base.urb_entry_size = ALIGN(output_size_bytes, 128) / 128; c.prog_data.output_topology = get_hw_prim_for_gl_prim(gp->program.OutputType); /* The GLSL linker will have already matched up GS inputs and the outputs * of prior stages. The driver does extend VS outputs in some cases, but * only for legacy OpenGL or Gen4-5 hardware, neither of which offer * geometry shader support. So we can safely ignore that. * * For SSO pipelines, we use a fixed VUE map layout based on variable * locations, so we can rely on rendezvous-by-location making this work. * * However, we need to ignore VARYING_SLOT_PRIMITIVE_ID, as it's not * written by previous stages and shows up via payload magic. */ GLbitfield64 inputs_read = gp->program.Base.InputsRead & ~VARYING_BIT_PRIMITIVE_ID; brw_compute_vue_map(brw->intelScreen->devinfo, &c.input_vue_map, inputs_read, prog->SeparateShader); /* GS inputs are read from the VUE 256 bits (2 vec4's) at a time, so we * need to program a URB read length of ceiling(num_slots / 2). */ c.prog_data.base.urb_read_length = (c.input_vue_map.num_slots + 1) / 2; void *mem_ctx = ralloc_context(NULL); unsigned program_size; const unsigned *program = brw_gs_emit(brw, prog, &c, mem_ctx, &program_size); if (program == NULL) { ralloc_free(mem_ctx); return false; } /* Scratch space is used for register spilling */ if (c.prog_data.base.base.total_scratch) { brw_get_scratch_bo(brw, &stage_state->scratch_bo, c.prog_data.base.base.total_scratch * brw->max_gs_threads); } brw_upload_cache(&brw->cache, BRW_CACHE_GS_PROG, &c.key, sizeof(c.key), program, program_size, &c.prog_data, sizeof(c.prog_data), &stage_state->prog_offset, &brw->gs.prog_data); ralloc_free(mem_ctx); return true; } static bool brw_gs_state_dirty(struct brw_context *brw) { return brw_state_dirty(brw, _NEW_TEXTURE, BRW_NEW_GEOMETRY_PROGRAM | BRW_NEW_TRANSFORM_FEEDBACK); } static void brw_gs_populate_key(struct brw_context *brw, struct brw_gs_prog_key *key) { struct gl_context *ctx = &brw->ctx; struct brw_stage_state *stage_state = &brw->gs.base; struct brw_geometry_program *gp = (struct brw_geometry_program *) brw->geometry_program; struct gl_program *prog = &gp->program.Base; memset(key, 0, sizeof(*key)); key->program_string_id = gp->id; /* _NEW_TEXTURE */ brw_populate_sampler_prog_key_data(ctx, prog, stage_state->sampler_count, &key->tex); } void brw_upload_gs_prog(struct brw_context *brw) { struct gl_context *ctx = &brw->ctx; struct gl_shader_program **current = ctx->_Shader->CurrentProgram; struct brw_stage_state *stage_state = &brw->gs.base; struct brw_gs_prog_key key; /* BRW_NEW_GEOMETRY_PROGRAM */ struct brw_geometry_program *gp = (struct brw_geometry_program *) brw->geometry_program; if (!brw_gs_state_dirty(brw)) return; if (gp == NULL) { /* No geometry shader. Vertex data just passes straight through. */ if (brw->gen == 6 && (brw->ctx.NewDriverState & BRW_NEW_TRANSFORM_FEEDBACK)) { gen6_brw_upload_ff_gs_prog(brw); return; } /* Other state atoms had better not try to access prog_data, since * there's no GS program. */ brw->gs.prog_data = NULL; brw->gs.base.prog_data = NULL; return; } brw_gs_populate_key(brw, &key); if (!brw_search_cache(&brw->cache, BRW_CACHE_GS_PROG, &key, sizeof(key), &stage_state->prog_offset, &brw->gs.prog_data)) { bool success = brw_codegen_gs_prog(brw, current[MESA_SHADER_GEOMETRY], gp, &key); assert(success); (void)success; } brw->gs.base.prog_data = &brw->gs.prog_data->base.base; } bool brw_gs_precompile(struct gl_context *ctx, struct gl_shader_program *shader_prog, struct gl_program *prog) { struct brw_context *brw = brw_context(ctx); struct brw_gs_prog_key key; uint32_t old_prog_offset = brw->gs.base.prog_offset; struct brw_gs_prog_data *old_prog_data = brw->gs.prog_data; bool success; struct gl_geometry_program *gp = (struct gl_geometry_program *) prog; struct brw_geometry_program *bgp = brw_geometry_program(gp); memset(&key, 0, sizeof(key)); brw_setup_tex_for_precompile(brw, &key.tex, prog); key.program_string_id = bgp->id; success = brw_codegen_gs_prog(brw, shader_prog, bgp, &key); brw->gs.base.prog_offset = old_prog_offset; brw->gs.prog_data = old_prog_data; return success; } bool brw_gs_prog_data_compare(const void *in_a, const void *in_b) { const struct brw_gs_prog_data *a = in_a; const struct brw_gs_prog_data *b = in_b; /* Compare the base structure. */ if (!brw_stage_prog_data_compare(&a->base.base, &b->base.base)) return false; /* Compare the rest of the struct. */ const unsigned offset = sizeof(struct brw_stage_prog_data); if (memcmp(((char *) a) + offset, ((char *) b) + offset, sizeof(struct brw_gs_prog_data) - offset)) { return false; } return true; }