/* * Copyright © 2011 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 * * This file computes the "VUE map" for a (non-fragment) shader stage, which * describes the layout of its output varyings. The VUE map is used to match * outputs from one stage with the inputs of the next. * * Largely, varyings can be placed however we like - producers/consumers simply * have to agree on the layout. However, there is also a "VUE Header" that * prescribes a fixed-layout for items that interact with fixed function * hardware, such as the clipper and rasterizer. * * Authors: * Paul Berry * Chris Forbes * Eric Anholt */ #include "brw_compiler.h" #include "dev/intel_debug.h" #include "brw_nir.h" static unsigned get_var_slots(gl_shader_stage stage, const nir_variable *var) { const struct glsl_type *type = var->type; if (nir_is_arrayed_io(var, stage)) { assert(glsl_type_is_array(type)); type = glsl_get_array_element(type); } /* EXT_mesh_shader: PRIMITIVE_INDICES is a flat array, not a proper arrayed * output, as opposed to D3D-style mesh shaders where it's addressed by the * primitive index. Prevent assigning several slots to primitive indices, * to avoid some issues. */ if (stage == MESA_SHADER_MESH && var->data.location == VARYING_SLOT_PRIMITIVE_INDICES && !nir_is_arrayed_io(var, stage)) return 1; return glsl_count_vec4_slots(type, false, var->data.bindless); } void brw_compute_per_primitive_map(int *out_per_primitive_map, uint32_t *out_per_primitive_stride, uint32_t *out_first_offset, uint32_t base_offset, nir_shader *nir, uint32_t variables_mode, uint64_t slots_valid, bool separate_shader) { memset(out_per_primitive_map, -1, sizeof(*out_per_primitive_map) * VARYING_SLOT_MAX); *out_per_primitive_stride = base_offset; *out_first_offset = UINT32_MAX; const uint64_t count_indices_bits = VARYING_BIT_PRIMITIVE_COUNT | VARYING_BIT_PRIMITIVE_INDICES; const uint64_t per_primitive_header_bits = VARYING_BIT_PRIMITIVE_SHADING_RATE | VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT | VARYING_BIT_CULL_PRIMITIVE; const uint64_t per_primitive_outputs_written = slots_valid & ~(count_indices_bits | per_primitive_header_bits); *out_first_offset = base_offset; /* We put each variable in its own 16B slot. Technically we could do a lot * better by allocating the space needed for the variable since the data is * constant and not interpolated for the fragment shader. Unfortunately the * backend treats those values similarly to vertex attributes and making * that change would require a pretty large change in the backend. Let's do * this later. */ /* Lay out builtins first */ const uint64_t builtins = per_primitive_outputs_written & BITFIELD64_MASK(VARYING_SLOT_VAR0); u_foreach_bit64(location, builtins) { assert(out_per_primitive_map[location] == -1); out_per_primitive_map[location] = *out_per_primitive_stride; *out_per_primitive_stride += 16; } uint32_t generics_offset = *out_per_primitive_stride; /* Lay out generics */ const uint64_t generics = per_primitive_outputs_written & ~BITFIELD64_MASK(VARYING_SLOT_VAR0); const int first_generic_output = ffsll(generics) - 1; u_foreach_bit64(location, generics) { assert(out_per_primitive_map[location] == -1); if (!separate_shader) { /* Just append the location at the back */ out_per_primitive_map[location] = *out_per_primitive_stride; } else { assert(location >= VARYING_SLOT_VAR0); /* Each location has its fixed spot */ out_per_primitive_map[location] = generics_offset + 16 * (location - first_generic_output); } *out_per_primitive_stride = MAX2(out_per_primitive_map[location] + 16, *out_per_primitive_stride); *out_first_offset = MIN2(out_per_primitive_map[location], *out_first_offset); } *out_first_offset = *out_first_offset == UINT32_MAX ? 0 : ROUND_DOWN_TO(*out_first_offset, 32); } static inline void assign_vue_slot(struct intel_vue_map *vue_map, int varying, int slot) { /* Make sure this varying hasn't been assigned a slot already */ assert (vue_map->varying_to_slot[varying] == -1); vue_map->varying_to_slot[varying] = slot; vue_map->slot_to_varying[slot] = varying; } /** * Compute the VUE map for a shader stage. */ void brw_compute_vue_map(const struct intel_device_info *devinfo, struct intel_vue_map *vue_map, uint64_t slots_valid, enum intel_vue_layout layout, uint32_t pos_slots) { vue_map->slots_valid = slots_valid; vue_map->layout = layout; if (layout != INTEL_VUE_LAYOUT_FIXED) { /* In SSO mode, we don't know whether the adjacent stage will * read/write gl_ClipDistance, which has a fixed slot location. * We have to assume the worst and reserve a slot for it, or else * the rest of our varyings will be off by a slot. * * Note that we don't have to worry about COL/BFC, as those built-in * variables only exist in legacy GL, which only supports VS and FS. */ slots_valid |= VARYING_BIT_CLIP_DIST0; slots_valid |= VARYING_BIT_CLIP_DIST1; } /* gl_Layer, gl_ViewportIndex & gl_PrimitiveShadingRateEXT don't get their * own varying slots -- they are stored in the first VUE slot * (VARYING_SLOT_PSIZ). */ slots_valid &= ~(VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT | VARYING_BIT_PRIMITIVE_SHADING_RATE); /* gl_FrontFace is provided somewhere else in the FS thread payload, it's * never in the VUE. */ slots_valid &= ~VARYING_BIT_FACE; /* Make sure that the values we store in vue_map->varying_to_slot and * vue_map->slot_to_varying won't overflow the signed chars that are used * to store them. Note that since vue_map->slot_to_varying sometimes holds * values equal to BRW_VARYING_SLOT_COUNT, we need to ensure that * BRW_VARYING_SLOT_COUNT is <= 127, not 128. */ STATIC_ASSERT(BRW_VARYING_SLOT_COUNT <= 127); for (int i = 0; i < BRW_VARYING_SLOT_COUNT; ++i) { vue_map->varying_to_slot[i] = -1; vue_map->slot_to_varying[i] = BRW_VARYING_SLOT_PAD; } int slot = 0; /* VUE header: format depends on chip generation and whether clipping is * enabled. * * See the Sandybridge PRM, Volume 2 Part 1, section 1.5.1 (page 30), * "Vertex URB Entry (VUE) Formats" which describes the VUE header layout. * * There are 8 or 16 DWs (D0-D15) in VUE header on Sandybridge: * dword 0-3 of the header is shading rate, indices, point width, clip flags. * dword 4-7 is the 4D space position * dword 8-15 of the vertex header is the user clip distance if * enabled. * dword 8-11 or 16-19 is the first vertex element data we fill. */ assign_vue_slot(vue_map, VARYING_SLOT_PSIZ, slot++); assign_vue_slot(vue_map, VARYING_SLOT_POS, slot++); /* When using Primitive Replication, multiple slots are used for storing * positions for each view. */ assert(pos_slots >= 1); if (pos_slots > 1) { for (int i = 1; i < pos_slots; i++) { vue_map->slot_to_varying[slot++] = VARYING_SLOT_POS; } } if (slots_valid & VARYING_BIT_CLIP_DIST0) assign_vue_slot(vue_map, VARYING_SLOT_CLIP_DIST0, slot++); if (slots_valid & VARYING_BIT_CLIP_DIST1) assign_vue_slot(vue_map, VARYING_SLOT_CLIP_DIST1, slot++); /* Vertex URB Formats table says: "Vertex Header shall be padded at the * end so that the header ends on a 32-byte boundary". */ slot += slot % 2; /* front and back colors need to be consecutive so that we can use * ATTRIBUTE_SWIZZLE_INPUTATTR_FACING to swizzle them when doing * two-sided color. */ if (slots_valid & VARYING_BIT_COL0) assign_vue_slot(vue_map, VARYING_SLOT_COL0, slot++); if (slots_valid & VARYING_BIT_BFC0) assign_vue_slot(vue_map, VARYING_SLOT_BFC0, slot++); if (slots_valid & VARYING_BIT_COL1) assign_vue_slot(vue_map, VARYING_SLOT_COL1, slot++); if (slots_valid & VARYING_BIT_BFC1) assign_vue_slot(vue_map, VARYING_SLOT_BFC1, slot++); /* The hardware doesn't care about the rest of the vertex outputs, so we * can assign them however we like. For normal programs, we simply assign * them contiguously. * * We generally don't need to assign a slot for VARYING_SLOT_CLIP_VERTEX, * since it's encoded as the clip distances by emit_clip_distances(). * However, it may be output by transform feedback, and we'd rather not * recompute state when TF changes, so we just always include it. */ if (layout != INTEL_VUE_LAYOUT_SEPARATE_MESH) { const uint64_t builtins = slots_valid & BITFIELD64_MASK(VARYING_SLOT_VAR0); u_foreach_bit64(varying, builtins) { /* Already assigned above? */ if (vue_map->varying_to_slot[varying] != -1) continue; assign_vue_slot(vue_map, varying, slot++); } } const int first_generic_slot = slot; const uint64_t generics = slots_valid & ~BITFIELD64_MASK(VARYING_SLOT_VAR0); u_foreach_bit64(varying, generics) { if (layout != INTEL_VUE_LAYOUT_FIXED) { slot = first_generic_slot + varying - VARYING_SLOT_VAR0; } assign_vue_slot(vue_map, varying, slot++); } if (layout == INTEL_VUE_LAYOUT_SEPARATE_MESH) { const uint64_t builtins = slots_valid & BITFIELD64_MASK(VARYING_SLOT_VAR0); u_foreach_bit64(varying, builtins) { /* Already assigned above? */ if (vue_map->varying_to_slot[varying] != -1) continue; assign_vue_slot(vue_map, varying, slot++); } } vue_map->num_slots = slot; vue_map->num_pos_slots = pos_slots; vue_map->num_per_vertex_slots = 0; vue_map->num_per_patch_slots = 0; } /** * Compute the VUE map for tessellation control shader outputs and * tessellation evaluation shader inputs. */ void brw_compute_tess_vue_map(struct intel_vue_map *vue_map, uint64_t vertex_slots, uint32_t patch_slots) { /* I don't think anything actually uses this... */ vue_map->slots_valid = vertex_slots; /* separate isn't really meaningful, we always compiled tessellation * shaders together, so use a fixed layout. */ vue_map->layout = INTEL_VUE_LAYOUT_FIXED; vertex_slots &= ~(VARYING_BIT_TESS_LEVEL_OUTER | VARYING_BIT_TESS_LEVEL_INNER); /* Make sure that the values we store in vue_map->varying_to_slot and * vue_map->slot_to_varying won't overflow the signed chars that are used * to store them. Note that since vue_map->slot_to_varying sometimes holds * values equal to VARYING_SLOT_TESS_MAX , we need to ensure that * VARYING_SLOT_TESS_MAX is <= 127, not 128. */ STATIC_ASSERT(VARYING_SLOT_TESS_MAX <= 127); for (int i = 0; i < VARYING_SLOT_TESS_MAX ; ++i) { vue_map->varying_to_slot[i] = -1; vue_map->slot_to_varying[i] = BRW_VARYING_SLOT_PAD; } int slot = 0; /* The first 8 DWords are reserved for the "Patch Header". * * VARYING_SLOT_TESS_LEVEL_OUTER / INNER live here, but the exact layout * depends on the domain type. They might not be in slots 0 and 1 as * described here, but pretending they're separate allows us to uniquely * identify them by distinct slot locations. */ assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_INNER, slot++); assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_OUTER, slot++); /* first assign per-patch varyings */ while (patch_slots != 0) { const int varying = ffsll(patch_slots) - 1; if (vue_map->varying_to_slot[varying + VARYING_SLOT_PATCH0] == -1) { assign_vue_slot(vue_map, varying + VARYING_SLOT_PATCH0, slot++); } patch_slots &= ~BITFIELD64_BIT(varying); } /* apparently, including the patch header... */ vue_map->num_per_patch_slots = slot; /* then assign per-vertex varyings for each vertex in our patch */ while (vertex_slots != 0) { const int varying = ffsll(vertex_slots) - 1; if (vue_map->varying_to_slot[varying] == -1) { assign_vue_slot(vue_map, varying, slot++); } vertex_slots &= ~BITFIELD64_BIT(varying); } vue_map->num_per_vertex_slots = slot - vue_map->num_per_patch_slots; vue_map->num_pos_slots = 0; vue_map->num_slots = slot; } static const char * varying_name(brw_varying_slot slot, gl_shader_stage stage) { assume(slot < BRW_VARYING_SLOT_COUNT); if (slot < VARYING_SLOT_MAX) return gl_varying_slot_name_for_stage((gl_varying_slot)slot, stage); static const char *brw_names[] = { [BRW_VARYING_SLOT_PAD - VARYING_SLOT_MAX] = "BRW_VARYING_SLOT_PAD", }; return brw_names[slot - VARYING_SLOT_MAX]; } void brw_print_vue_map(FILE *fp, const struct intel_vue_map *vue_map, gl_shader_stage stage) { const char *layout_name = vue_map->layout == INTEL_VUE_LAYOUT_FIXED ? "fixed" : vue_map->layout == INTEL_VUE_LAYOUT_SEPARATE ? "separate" : "separate-mesh"; if (vue_map->num_per_vertex_slots > 0 || vue_map->num_per_patch_slots > 0) { fprintf(fp, "PUE map (%d slots, %d/patch, %d/vertex, %s)\n", vue_map->num_slots, vue_map->num_per_patch_slots, vue_map->num_per_vertex_slots, layout_name); for (int i = 0; i < vue_map->num_slots; i++) { if (vue_map->slot_to_varying[i] >= VARYING_SLOT_PATCH0) { fprintf(fp, " [%02d] VARYING_SLOT_PATCH%d\n", i, vue_map->slot_to_varying[i] - VARYING_SLOT_PATCH0); } else { fprintf(fp, " [%02d] %s\n", i, varying_name(vue_map->slot_to_varying[i], stage)); } } } else { fprintf(fp, "%s VUE map (%d slots, %s)\n", gl_shader_stage_name(stage), vue_map->num_slots, layout_name); for (int i = 0; i < vue_map->num_slots; i++) { fprintf(fp, " [%02d] %s\n", i, varying_name(vue_map->slot_to_varying[i], stage)); } } fprintf(fp, "\n"); }