/* * Copyright © 2010 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_fs_visitor.cpp * * This file supports generating the FS LIR from the GLSL IR. The LIR * makes it easier to do backend-specific optimizations than doing so * in the GLSL IR or in the native code. */ #include "brw_fs.h" #include "compiler/glsl_types.h" using namespace brw; /* Sample from the MCS surface attached to this multisample texture. */ fs_reg fs_visitor::emit_mcs_fetch(const fs_reg &coordinate, unsigned components, const fs_reg &texture, const fs_reg &texture_handle) { const fs_reg dest = vgrf(glsl_type::uvec4_type); fs_reg srcs[TEX_LOGICAL_NUM_SRCS]; srcs[TEX_LOGICAL_SRC_COORDINATE] = coordinate; srcs[TEX_LOGICAL_SRC_SURFACE] = texture; srcs[TEX_LOGICAL_SRC_SAMPLER] = brw_imm_ud(0); srcs[TEX_LOGICAL_SRC_SURFACE_HANDLE] = texture_handle; srcs[TEX_LOGICAL_SRC_COORD_COMPONENTS] = brw_imm_d(components); srcs[TEX_LOGICAL_SRC_GRAD_COMPONENTS] = brw_imm_d(0); fs_inst *inst = bld.emit(SHADER_OPCODE_TXF_MCS_LOGICAL, dest, srcs, ARRAY_SIZE(srcs)); /* We only care about one or two regs of response, but the sampler always * writes 4/8. */ inst->size_written = 4 * dest.component_size(inst->exec_size); return dest; } /** * Apply workarounds for Gen6 gather with UINT/SINT */ void fs_visitor::emit_gen6_gather_wa(uint8_t wa, fs_reg dst) { if (!wa) return; int width = (wa & WA_8BIT) ? 8 : 16; for (int i = 0; i < 4; i++) { fs_reg dst_f = retype(dst, BRW_REGISTER_TYPE_F); /* Convert from UNORM to UINT */ bld.MUL(dst_f, dst_f, brw_imm_f((1 << width) - 1)); bld.MOV(dst, dst_f); if (wa & WA_SIGN) { /* Reinterpret the UINT value as a signed INT value by * shifting the sign bit into place, then shifting back * preserving sign. */ bld.SHL(dst, dst, brw_imm_d(32 - width)); bld.ASR(dst, dst, brw_imm_d(32 - width)); } dst = offset(dst, bld, 1); } } /** Emits a dummy fragment shader consisting of magenta for bringup purposes. */ void fs_visitor::emit_dummy_fs() { int reg_width = dispatch_width / 8; /* Everyone's favorite color. */ const float color[4] = { 1.0, 0.0, 1.0, 0.0 }; for (int i = 0; i < 4; i++) { bld.MOV(fs_reg(MRF, 2 + i * reg_width, BRW_REGISTER_TYPE_F), brw_imm_f(color[i])); } fs_inst *write; write = bld.emit(FS_OPCODE_FB_WRITE); write->eot = true; write->last_rt = true; if (devinfo->gen >= 6) { write->base_mrf = 2; write->mlen = 4 * reg_width; } else { write->header_size = 2; write->base_mrf = 0; write->mlen = 2 + 4 * reg_width; } /* Tell the SF we don't have any inputs. Gen4-5 require at least one * varying to avoid GPU hangs, so set that. */ struct brw_wm_prog_data *wm_prog_data = brw_wm_prog_data(this->prog_data); wm_prog_data->num_varying_inputs = devinfo->gen < 6 ? 1 : 0; memset(wm_prog_data->urb_setup, -1, sizeof(wm_prog_data->urb_setup[0]) * VARYING_SLOT_MAX); brw_compute_urb_setup_index(wm_prog_data); /* We don't have any uniforms. */ stage_prog_data->nr_params = 0; stage_prog_data->nr_pull_params = 0; stage_prog_data->curb_read_length = 0; stage_prog_data->dispatch_grf_start_reg = 2; wm_prog_data->dispatch_grf_start_reg_16 = 2; wm_prog_data->dispatch_grf_start_reg_32 = 2; grf_used = 1; /* Gen4-5 don't allow zero GRF blocks */ calculate_cfg(); } /* The register location here is relative to the start of the URB * data. It will get adjusted to be a real location before * generate_code() time. */ fs_reg fs_visitor::interp_reg(int location, int channel) { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *prog_data = brw_wm_prog_data(this->prog_data); int regnr = prog_data->urb_setup[location] * 4 + channel; assert(prog_data->urb_setup[location] != -1); return fs_reg(ATTR, regnr, BRW_REGISTER_TYPE_F); } /** Emits the interpolation for the varying inputs. */ void fs_visitor::emit_interpolation_setup_gen4() { struct brw_reg g1_uw = retype(brw_vec1_grf(1, 0), BRW_REGISTER_TYPE_UW); fs_builder abld = bld.annotate("compute pixel centers"); this->pixel_x = vgrf(glsl_type::uint_type); this->pixel_y = vgrf(glsl_type::uint_type); this->pixel_x.type = BRW_REGISTER_TYPE_UW; this->pixel_y.type = BRW_REGISTER_TYPE_UW; abld.ADD(this->pixel_x, fs_reg(stride(suboffset(g1_uw, 4), 2, 4, 0)), fs_reg(brw_imm_v(0x10101010))); abld.ADD(this->pixel_y, fs_reg(stride(suboffset(g1_uw, 5), 2, 4, 0)), fs_reg(brw_imm_v(0x11001100))); abld = bld.annotate("compute pixel deltas from v0"); this->delta_xy[BRW_BARYCENTRIC_PERSPECTIVE_PIXEL] = vgrf(glsl_type::vec2_type); const fs_reg &delta_xy = this->delta_xy[BRW_BARYCENTRIC_PERSPECTIVE_PIXEL]; const fs_reg xstart(negate(brw_vec1_grf(1, 0))); const fs_reg ystart(negate(brw_vec1_grf(1, 1))); if (devinfo->has_pln) { for (unsigned i = 0; i < dispatch_width / 8; i++) { abld.quarter(i).ADD(quarter(offset(delta_xy, abld, 0), i), quarter(this->pixel_x, i), xstart); abld.quarter(i).ADD(quarter(offset(delta_xy, abld, 1), i), quarter(this->pixel_y, i), ystart); } } else { abld.ADD(offset(delta_xy, abld, 0), this->pixel_x, xstart); abld.ADD(offset(delta_xy, abld, 1), this->pixel_y, ystart); } abld = bld.annotate("compute pos.w and 1/pos.w"); /* Compute wpos.w. It's always in our setup, since it's needed to * interpolate the other attributes. */ this->wpos_w = vgrf(glsl_type::float_type); abld.emit(FS_OPCODE_LINTERP, wpos_w, delta_xy, component(interp_reg(VARYING_SLOT_POS, 3), 0)); /* Compute the pixel 1/W value from wpos.w. */ this->pixel_w = vgrf(glsl_type::float_type); abld.emit(SHADER_OPCODE_RCP, this->pixel_w, wpos_w); } static unsigned brw_rnd_mode_from_nir(unsigned mode, unsigned *mask) { unsigned brw_mode = 0; *mask = 0; if ((FLOAT_CONTROLS_ROUNDING_MODE_RTZ_FP16 | FLOAT_CONTROLS_ROUNDING_MODE_RTZ_FP32 | FLOAT_CONTROLS_ROUNDING_MODE_RTZ_FP64) & mode) { brw_mode |= BRW_RND_MODE_RTZ << BRW_CR0_RND_MODE_SHIFT; *mask |= BRW_CR0_RND_MODE_MASK; } if ((FLOAT_CONTROLS_ROUNDING_MODE_RTE_FP16 | FLOAT_CONTROLS_ROUNDING_MODE_RTE_FP32 | FLOAT_CONTROLS_ROUNDING_MODE_RTE_FP64) & mode) { brw_mode |= BRW_RND_MODE_RTNE << BRW_CR0_RND_MODE_SHIFT; *mask |= BRW_CR0_RND_MODE_MASK; } if (mode & FLOAT_CONTROLS_DENORM_PRESERVE_FP16) { brw_mode |= BRW_CR0_FP16_DENORM_PRESERVE; *mask |= BRW_CR0_FP16_DENORM_PRESERVE; } if (mode & FLOAT_CONTROLS_DENORM_PRESERVE_FP32) { brw_mode |= BRW_CR0_FP32_DENORM_PRESERVE; *mask |= BRW_CR0_FP32_DENORM_PRESERVE; } if (mode & FLOAT_CONTROLS_DENORM_PRESERVE_FP64) { brw_mode |= BRW_CR0_FP64_DENORM_PRESERVE; *mask |= BRW_CR0_FP64_DENORM_PRESERVE; } if (mode & FLOAT_CONTROLS_DENORM_FLUSH_TO_ZERO_FP16) *mask |= BRW_CR0_FP16_DENORM_PRESERVE; if (mode & FLOAT_CONTROLS_DENORM_FLUSH_TO_ZERO_FP32) *mask |= BRW_CR0_FP32_DENORM_PRESERVE; if (mode & FLOAT_CONTROLS_DENORM_FLUSH_TO_ZERO_FP64) *mask |= BRW_CR0_FP64_DENORM_PRESERVE; if (mode == FLOAT_CONTROLS_DEFAULT_FLOAT_CONTROL_MODE) *mask |= BRW_CR0_FP_MODE_MASK; return brw_mode; } void fs_visitor::emit_shader_float_controls_execution_mode() { unsigned execution_mode = this->nir->info.float_controls_execution_mode; if (execution_mode == FLOAT_CONTROLS_DEFAULT_FLOAT_CONTROL_MODE) return; fs_builder abld = bld.annotate("shader floats control execution mode"); unsigned mask = 0; unsigned mode = brw_rnd_mode_from_nir(execution_mode, &mask); abld.emit(SHADER_OPCODE_FLOAT_CONTROL_MODE, bld.null_reg_ud(), brw_imm_d(mode), brw_imm_d(mask)); } /** Emits the interpolation for the varying inputs. */ void fs_visitor::emit_interpolation_setup_gen6() { fs_builder abld = bld.annotate("compute pixel centers"); this->pixel_x = vgrf(glsl_type::float_type); this->pixel_y = vgrf(glsl_type::float_type); for (unsigned i = 0; i < DIV_ROUND_UP(dispatch_width, 16); i++) { const fs_builder hbld = abld.group(MIN2(16, dispatch_width), i); struct brw_reg gi_uw = retype(brw_vec1_grf(1 + i, 0), BRW_REGISTER_TYPE_UW); if (devinfo->gen >= 8 || dispatch_width == 8) { /* The "Register Region Restrictions" page says for BDW (and newer, * presumably): * * "When destination spans two registers, the source may be one or * two registers. The destination elements must be evenly split * between the two registers." * * Thus we can do a single add(16) in SIMD8 or an add(32) in SIMD16 * to compute our pixel centers. */ const fs_builder dbld = abld.exec_all().group(hbld.dispatch_width() * 2, 0); fs_reg int_pixel_xy = dbld.vgrf(BRW_REGISTER_TYPE_UW); dbld.ADD(int_pixel_xy, fs_reg(stride(suboffset(gi_uw, 4), 1, 4, 0)), fs_reg(brw_imm_v(0x11001010))); hbld.emit(FS_OPCODE_PIXEL_X, offset(pixel_x, hbld, i), int_pixel_xy); hbld.emit(FS_OPCODE_PIXEL_Y, offset(pixel_y, hbld, i), int_pixel_xy); } else { /* The "Register Region Restrictions" page says for SNB, IVB, HSW: * * "When destination spans two registers, the source MUST span * two registers." * * Since the GRF source of the ADD will only read a single register, * we must do two separate ADDs in SIMD16. */ const fs_reg int_pixel_x = hbld.vgrf(BRW_REGISTER_TYPE_UW); const fs_reg int_pixel_y = hbld.vgrf(BRW_REGISTER_TYPE_UW); hbld.ADD(int_pixel_x, fs_reg(stride(suboffset(gi_uw, 4), 2, 4, 0)), fs_reg(brw_imm_v(0x10101010))); hbld.ADD(int_pixel_y, fs_reg(stride(suboffset(gi_uw, 5), 2, 4, 0)), fs_reg(brw_imm_v(0x11001100))); /* As of gen6, we can no longer mix float and int sources. We have * to turn the integer pixel centers into floats for their actual * use. */ hbld.MOV(offset(pixel_x, hbld, i), int_pixel_x); hbld.MOV(offset(pixel_y, hbld, i), int_pixel_y); } } abld = bld.annotate("compute pos.w"); this->pixel_w = fetch_payload_reg(abld, payload.source_w_reg); this->wpos_w = vgrf(glsl_type::float_type); abld.emit(SHADER_OPCODE_RCP, this->wpos_w, this->pixel_w); struct brw_wm_prog_data *wm_prog_data = brw_wm_prog_data(prog_data); for (int i = 0; i < BRW_BARYCENTRIC_MODE_COUNT; ++i) { this->delta_xy[i] = fetch_barycentric_reg( bld, payload.barycentric_coord_reg[i]); } uint32_t centroid_modes = wm_prog_data->barycentric_interp_modes & (1 << BRW_BARYCENTRIC_PERSPECTIVE_CENTROID | 1 << BRW_BARYCENTRIC_NONPERSPECTIVE_CENTROID); if (devinfo->needs_unlit_centroid_workaround && centroid_modes) { /* Get the pixel/sample mask into f0 so that we know which * pixels are lit. Then, for each channel that is unlit, * replace the centroid data with non-centroid data. */ for (unsigned i = 0; i < DIV_ROUND_UP(dispatch_width, 16); i++) { bld.exec_all().group(1, 0) .MOV(retype(brw_flag_reg(0, i), BRW_REGISTER_TYPE_UW), retype(brw_vec1_grf(1 + i, 7), BRW_REGISTER_TYPE_UW)); } for (int i = 0; i < BRW_BARYCENTRIC_MODE_COUNT; ++i) { if (!(centroid_modes & (1 << i))) continue; const fs_reg centroid_delta_xy = delta_xy[i]; const fs_reg &pixel_delta_xy = delta_xy[i - 1]; delta_xy[i] = bld.vgrf(BRW_REGISTER_TYPE_F, 2); for (unsigned c = 0; c < 2; c++) { for (unsigned q = 0; q < dispatch_width / 8; q++) { set_predicate(BRW_PREDICATE_NORMAL, bld.quarter(q).SEL( quarter(offset(delta_xy[i], bld, c), q), quarter(offset(centroid_delta_xy, bld, c), q), quarter(offset(pixel_delta_xy, bld, c), q))); } } } } } static enum brw_conditional_mod cond_for_alpha_func(GLenum func) { switch(func) { case GL_GREATER: return BRW_CONDITIONAL_G; case GL_GEQUAL: return BRW_CONDITIONAL_GE; case GL_LESS: return BRW_CONDITIONAL_L; case GL_LEQUAL: return BRW_CONDITIONAL_LE; case GL_EQUAL: return BRW_CONDITIONAL_EQ; case GL_NOTEQUAL: return BRW_CONDITIONAL_NEQ; default: unreachable("Not reached"); } } /** * Alpha test support for when we compile it into the shader instead * of using the normal fixed-function alpha test. */ void fs_visitor::emit_alpha_test() { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; const fs_builder abld = bld.annotate("Alpha test"); fs_inst *cmp; if (key->alpha_test_func == GL_ALWAYS) return; if (key->alpha_test_func == GL_NEVER) { /* f0.1 = 0 */ fs_reg some_reg = fs_reg(retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UW)); cmp = abld.CMP(bld.null_reg_f(), some_reg, some_reg, BRW_CONDITIONAL_NEQ); } else { /* RT0 alpha */ fs_reg color = offset(outputs[0], bld, 3); /* f0.1 &= func(color, ref) */ cmp = abld.CMP(bld.null_reg_f(), color, brw_imm_f(key->alpha_test_ref), cond_for_alpha_func(key->alpha_test_func)); } cmp->predicate = BRW_PREDICATE_NORMAL; cmp->flag_subreg = 1; } fs_inst * fs_visitor::emit_single_fb_write(const fs_builder &bld, fs_reg color0, fs_reg color1, fs_reg src0_alpha, unsigned components) { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *prog_data = brw_wm_prog_data(this->prog_data); /* Hand over gl_FragDepth or the payload depth. */ const fs_reg dst_depth = fetch_payload_reg(bld, payload.dest_depth_reg); fs_reg src_depth, src_stencil; if (source_depth_to_render_target) { if (nir->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) src_depth = frag_depth; else src_depth = fetch_payload_reg(bld, payload.source_depth_reg); } if (nir->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_STENCIL)) src_stencil = frag_stencil; const fs_reg sources[] = { color0, color1, src0_alpha, src_depth, dst_depth, src_stencil, (prog_data->uses_omask ? sample_mask : fs_reg()), brw_imm_ud(components) }; assert(ARRAY_SIZE(sources) - 1 == FB_WRITE_LOGICAL_SRC_COMPONENTS); fs_inst *write = bld.emit(FS_OPCODE_FB_WRITE_LOGICAL, fs_reg(), sources, ARRAY_SIZE(sources)); if (prog_data->uses_kill) { write->predicate = BRW_PREDICATE_NORMAL; write->flag_subreg = sample_mask_flag_subreg(this); } return write; } void fs_visitor::emit_fb_writes() { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *prog_data = brw_wm_prog_data(this->prog_data); brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; fs_inst *inst = NULL; if (source_depth_to_render_target && devinfo->gen == 6) { /* For outputting oDepth on gen6, SIMD8 writes have to be used. This * would require SIMD8 moves of each half to message regs, e.g. by using * the SIMD lowering pass. Unfortunately this is more difficult than it * sounds because the SIMD8 single-source message lacks channel selects * for the second and third subspans. */ limit_dispatch_width(8, "Depth writes unsupported in SIMD16+ mode.\n"); } if (nir->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_STENCIL)) { /* From the 'Render Target Write message' section of the docs: * "Output Stencil is not supported with SIMD16 Render Target Write * Messages." */ limit_dispatch_width(8, "gl_FragStencilRefARB unsupported " "in SIMD16+ mode.\n"); } /* ANV doesn't know about sample mask output during the wm key creation * so we compute if we need replicate alpha and emit alpha to coverage * workaround here. */ const bool replicate_alpha = key->alpha_test_replicate_alpha || (key->nr_color_regions > 1 && key->alpha_to_coverage && (sample_mask.file == BAD_FILE || devinfo->gen == 6)); for (int target = 0; target < key->nr_color_regions; target++) { /* Skip over outputs that weren't written. */ if (this->outputs[target].file == BAD_FILE) continue; const fs_builder abld = bld.annotate( ralloc_asprintf(this->mem_ctx, "FB write target %d", target)); fs_reg src0_alpha; if (devinfo->gen >= 6 && replicate_alpha && target != 0) src0_alpha = offset(outputs[0], bld, 3); inst = emit_single_fb_write(abld, this->outputs[target], this->dual_src_output, src0_alpha, 4); inst->target = target; } prog_data->dual_src_blend = (this->dual_src_output.file != BAD_FILE && this->outputs[0].file != BAD_FILE); assert(!prog_data->dual_src_blend || key->nr_color_regions == 1); if (inst == NULL) { /* Even if there's no color buffers enabled, we still need to send * alpha out the pipeline to our null renderbuffer to support * alpha-testing, alpha-to-coverage, and so on. */ /* FINISHME: Factor out this frequently recurring pattern into a * helper function. */ const fs_reg srcs[] = { reg_undef, reg_undef, reg_undef, offset(this->outputs[0], bld, 3) }; const fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_UD, 4); bld.LOAD_PAYLOAD(tmp, srcs, 4, 0); inst = emit_single_fb_write(bld, tmp, reg_undef, reg_undef, 4); inst->target = 0; } inst->last_rt = true; inst->eot = true; if (devinfo->gen >= 11 && devinfo->gen <= 12 && prog_data->dual_src_blend) { /* The dual-source RT write messages fail to release the thread * dependency on ICL and TGL with SIMD32 dispatch, leading to hangs. * * XXX - Emit an extra single-source NULL RT-write marked LastRT in * order to release the thread dependency without disabling * SIMD32. * * The dual-source RT write messages may lead to hangs with SIMD16 * dispatch on ICL due some unknown reasons, see * https://gitlab.freedesktop.org/mesa/mesa/-/issues/2183 */ limit_dispatch_width(8, "Dual source blending unsupported " "in SIMD16 and SIMD32 modes.\n"); } } void fs_visitor::emit_urb_writes(const fs_reg &gs_vertex_count) { int slot, urb_offset, length; int starting_urb_offset = 0; const struct brw_vue_prog_data *vue_prog_data = brw_vue_prog_data(this->prog_data); const struct brw_vs_prog_key *vs_key = (const struct brw_vs_prog_key *) this->key; const GLbitfield64 psiz_mask = VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT | VARYING_BIT_PSIZ; const struct brw_vue_map *vue_map = &vue_prog_data->vue_map; bool flush; fs_reg sources[8]; fs_reg urb_handle; if (stage == MESA_SHADER_TESS_EVAL) urb_handle = fs_reg(retype(brw_vec8_grf(4, 0), BRW_REGISTER_TYPE_UD)); else urb_handle = fs_reg(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD)); opcode opcode = SHADER_OPCODE_URB_WRITE_SIMD8; int header_size = 1; fs_reg per_slot_offsets; if (stage == MESA_SHADER_GEOMETRY) { const struct brw_gs_prog_data *gs_prog_data = brw_gs_prog_data(this->prog_data); /* We need to increment the Global Offset to skip over the control data * header and the extra "Vertex Count" field (1 HWord) at the beginning * of the VUE. We're counting in OWords, so the units are doubled. */ starting_urb_offset = 2 * gs_prog_data->control_data_header_size_hwords; if (gs_prog_data->static_vertex_count == -1) starting_urb_offset += 2; /* We also need to use per-slot offsets. The per-slot offset is the * Vertex Count. SIMD8 mode processes 8 different primitives at a * time; each may output a different number of vertices. */ opcode = SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT; header_size++; /* The URB offset is in 128-bit units, so we need to multiply by 2 */ const int output_vertex_size_owords = gs_prog_data->output_vertex_size_hwords * 2; if (gs_vertex_count.file == IMM) { per_slot_offsets = brw_imm_ud(output_vertex_size_owords * gs_vertex_count.ud); } else { per_slot_offsets = vgrf(glsl_type::uint_type); bld.MUL(per_slot_offsets, gs_vertex_count, brw_imm_ud(output_vertex_size_owords)); } } length = 0; urb_offset = starting_urb_offset; flush = false; /* SSO shaders can have VUE slots allocated which are never actually * written to, so ignore them when looking for the last (written) slot. */ int last_slot = vue_map->num_slots - 1; while (last_slot > 0 && (vue_map->slot_to_varying[last_slot] == BRW_VARYING_SLOT_PAD || outputs[vue_map->slot_to_varying[last_slot]].file == BAD_FILE)) { last_slot--; } bool urb_written = false; for (slot = 0; slot < vue_map->num_slots; slot++) { int varying = vue_map->slot_to_varying[slot]; switch (varying) { case VARYING_SLOT_PSIZ: { /* The point size varying slot is the vue header and is always in the * vue map. But often none of the special varyings that live there * are written and in that case we can skip writing to the vue * header, provided the corresponding state properly clamps the * values further down the pipeline. */ if ((vue_map->slots_valid & psiz_mask) == 0) { assert(length == 0); urb_offset++; break; } fs_reg zero(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); bld.MOV(zero, brw_imm_ud(0u)); sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_LAYER) sources[length++] = this->outputs[VARYING_SLOT_LAYER]; else sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_VIEWPORT) sources[length++] = this->outputs[VARYING_SLOT_VIEWPORT]; else sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_PSIZ) sources[length++] = this->outputs[VARYING_SLOT_PSIZ]; else sources[length++] = zero; break; } case BRW_VARYING_SLOT_NDC: case VARYING_SLOT_EDGE: unreachable("unexpected scalar vs output"); break; default: /* gl_Position is always in the vue map, but isn't always written by * the shader. Other varyings (clip distances) get added to the vue * map but don't always get written. In those cases, the * corresponding this->output[] slot will be invalid we and can skip * the urb write for the varying. If we've already queued up a vue * slot for writing we flush a mlen 5 urb write, otherwise we just * advance the urb_offset. */ if (varying == BRW_VARYING_SLOT_PAD || this->outputs[varying].file == BAD_FILE) { if (length > 0) flush = true; else urb_offset++; break; } if (stage == MESA_SHADER_VERTEX && vs_key->clamp_vertex_color && (varying == VARYING_SLOT_COL0 || varying == VARYING_SLOT_COL1 || varying == VARYING_SLOT_BFC0 || varying == VARYING_SLOT_BFC1)) { /* We need to clamp these guys, so do a saturating MOV into a * temp register and use that for the payload. */ for (int i = 0; i < 4; i++) { fs_reg reg = fs_reg(VGRF, alloc.allocate(1), outputs[varying].type); fs_reg src = offset(this->outputs[varying], bld, i); set_saturate(true, bld.MOV(reg, src)); sources[length++] = reg; } } else { int slot_offset = 0; /* When using Primitive Replication, there may be multiple slots * assigned to POS. */ if (varying == VARYING_SLOT_POS) slot_offset = slot - vue_map->varying_to_slot[VARYING_SLOT_POS]; for (unsigned i = 0; i < 4; i++) { sources[length++] = offset(this->outputs[varying], bld, i + (slot_offset * 4)); } } break; } const fs_builder abld = bld.annotate("URB write"); /* If we've queued up 8 registers of payload (2 VUE slots), if this is * the last slot or if we need to flush (see BAD_FILE varying case * above), emit a URB write send now to flush out the data. */ if (length == 8 || (length > 0 && slot == last_slot)) flush = true; if (flush) { fs_reg *payload_sources = ralloc_array(mem_ctx, fs_reg, length + header_size); fs_reg payload = fs_reg(VGRF, alloc.allocate(length + header_size), BRW_REGISTER_TYPE_F); payload_sources[0] = urb_handle; if (opcode == SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT) payload_sources[1] = per_slot_offsets; memcpy(&payload_sources[header_size], sources, length * sizeof sources[0]); abld.LOAD_PAYLOAD(payload, payload_sources, length + header_size, header_size); fs_inst *inst = abld.emit(opcode, reg_undef, payload); /* For ICL WA 1805992985 one needs additional write in the end. */ if (devinfo->gen == 11 && stage == MESA_SHADER_TESS_EVAL) inst->eot = false; else inst->eot = slot == last_slot && stage != MESA_SHADER_GEOMETRY; inst->mlen = length + header_size; inst->offset = urb_offset; urb_offset = starting_urb_offset + slot + 1; length = 0; flush = false; urb_written = true; } } /* If we don't have any valid slots to write, just do a minimal urb write * send to terminate the shader. This includes 1 slot of undefined data, * because it's invalid to write 0 data: * * From the Broadwell PRM, Volume 7: 3D Media GPGPU, Shared Functions - * Unified Return Buffer (URB) > URB_SIMD8_Write and URB_SIMD8_Read > * Write Data Payload: * * "The write data payload can be between 1 and 8 message phases long." */ if (!urb_written) { /* For GS, just turn EmitVertex() into a no-op. We don't want it to * end the thread, and emit_gs_thread_end() already emits a SEND with * EOT at the end of the program for us. */ if (stage == MESA_SHADER_GEOMETRY) return; fs_reg payload = fs_reg(VGRF, alloc.allocate(2), BRW_REGISTER_TYPE_UD); bld.exec_all().MOV(payload, urb_handle); fs_inst *inst = bld.emit(SHADER_OPCODE_URB_WRITE_SIMD8, reg_undef, payload); inst->eot = true; inst->mlen = 2; inst->offset = 1; return; } /* ICL WA 1805992985: * * ICLLP GPU hangs on one of tessellation vkcts tests with DS not done. The * send cycle, which is a urb write with an eot must be 4 phases long and * all 8 lanes must valid. */ if (devinfo->gen == 11 && stage == MESA_SHADER_TESS_EVAL) { fs_reg payload = fs_reg(VGRF, alloc.allocate(6), BRW_REGISTER_TYPE_UD); /* Workaround requires all 8 channels (lanes) to be valid. This is * understood to mean they all need to be alive. First trick is to find * a live channel and copy its urb handle for all the other channels to * make sure all handles are valid. */ bld.exec_all().MOV(payload, bld.emit_uniformize(urb_handle)); /* Second trick is to use masked URB write where one can tell the HW to * actually write data only for selected channels even though all are * active. * Third trick is to take advantage of the must-be-zero (MBZ) area in * the very beginning of the URB. * * One masks data to be written only for the first channel and uses * offset zero explicitly to land data to the MBZ area avoiding trashing * any other part of the URB. * * Since the WA says that the write needs to be 4 phases long one uses * 4 slots data. All are explicitly zeros in order to to keep the MBZ * area written as zeros. */ bld.exec_all().MOV(offset(payload, bld, 1), brw_imm_ud(0x10000u)); bld.exec_all().MOV(offset(payload, bld, 2), brw_imm_ud(0u)); bld.exec_all().MOV(offset(payload, bld, 3), brw_imm_ud(0u)); bld.exec_all().MOV(offset(payload, bld, 4), brw_imm_ud(0u)); bld.exec_all().MOV(offset(payload, bld, 5), brw_imm_ud(0u)); fs_inst *inst = bld.exec_all().emit(SHADER_OPCODE_URB_WRITE_SIMD8_MASKED, reg_undef, payload); inst->eot = true; inst->mlen = 6; inst->offset = 0; } } void fs_visitor::emit_cs_terminate() { assert(devinfo->gen >= 7); /* We are getting the thread ID from the compute shader header */ assert(stage == MESA_SHADER_COMPUTE); /* We can't directly send from g0, since sends with EOT have to use * g112-127. So, copy it to a virtual register, The register allocator will * make sure it uses the appropriate register range. */ struct brw_reg g0 = retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD); fs_reg payload = fs_reg(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); bld.group(8, 0).exec_all().MOV(payload, g0); /* Send a message to the thread spawner to terminate the thread. */ fs_inst *inst = bld.exec_all() .emit(CS_OPCODE_CS_TERMINATE, reg_undef, payload); inst->eot = true; } void fs_visitor::emit_barrier() { uint32_t barrier_id_mask; switch (devinfo->gen) { case 7: case 8: barrier_id_mask = 0x0f000000u; break; case 9: case 10: barrier_id_mask = 0x8f000000u; break; case 11: case 12: barrier_id_mask = 0x7f000000u; break; default: unreachable("barrier is only available on gen >= 7"); } /* We are getting the barrier ID from the compute shader header */ assert(stage == MESA_SHADER_COMPUTE); fs_reg payload = fs_reg(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* Clear the message payload */ bld.exec_all().group(8, 0).MOV(payload, brw_imm_ud(0u)); /* Copy the barrier id from r0.2 to the message payload reg.2 */ fs_reg r0_2 = fs_reg(retype(brw_vec1_grf(0, 2), BRW_REGISTER_TYPE_UD)); bld.exec_all().group(1, 0).AND(component(payload, 2), r0_2, brw_imm_ud(barrier_id_mask)); /* Emit a gateway "barrier" message using the payload we set up, followed * by a wait instruction. */ bld.exec_all().emit(SHADER_OPCODE_BARRIER, reg_undef, payload); } fs_visitor::fs_visitor(const struct brw_compiler *compiler, void *log_data, void *mem_ctx, const brw_base_prog_key *key, struct brw_stage_prog_data *prog_data, const nir_shader *shader, unsigned dispatch_width, int shader_time_index, const struct brw_vue_map *input_vue_map) : backend_shader(compiler, log_data, mem_ctx, shader, prog_data), key(key), gs_compile(NULL), prog_data(prog_data), input_vue_map(input_vue_map), live_analysis(this), regpressure_analysis(this), performance_analysis(this), dispatch_width(dispatch_width), shader_time_index(shader_time_index), bld(fs_builder(this, dispatch_width).at_end()) { init(); } fs_visitor::fs_visitor(const struct brw_compiler *compiler, void *log_data, void *mem_ctx, struct brw_gs_compile *c, struct brw_gs_prog_data *prog_data, const nir_shader *shader, int shader_time_index) : backend_shader(compiler, log_data, mem_ctx, shader, &prog_data->base.base), key(&c->key.base), gs_compile(c), prog_data(&prog_data->base.base), live_analysis(this), regpressure_analysis(this), performance_analysis(this), dispatch_width(8), shader_time_index(shader_time_index), bld(fs_builder(this, dispatch_width).at_end()) { init(); } void fs_visitor::init() { if (key) this->key_tex = &key->tex; else this->key_tex = NULL; this->max_dispatch_width = 32; this->prog_data = this->stage_prog_data; this->failed = false; this->nir_locals = NULL; this->nir_ssa_values = NULL; memset(&this->payload, 0, sizeof(this->payload)); this->source_depth_to_render_target = false; this->runtime_check_aads_emit = false; this->first_non_payload_grf = 0; this->max_grf = devinfo->gen >= 7 ? GEN7_MRF_HACK_START : BRW_MAX_GRF; this->uniforms = 0; this->last_scratch = 0; this->pull_constant_loc = NULL; this->push_constant_loc = NULL; this->shader_stats.scheduler_mode = NULL; this->shader_stats.promoted_constants = 0, this->grf_used = 0; this->spilled_any_registers = false; } fs_visitor::~fs_visitor() { }