/* * 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.cpp * * This file drives the GLSL IR -> LIR translation, contains the * optimizations on the LIR, and drives the generation of native code * from the LIR. */ #include "main/macros.h" #include "brw_eu.h" #include "brw_fs.h" #include "brw_nir.h" #include "brw_vec4_gs_visitor.h" #include "brw_cfg.h" #include "brw_dead_control_flow.h" #include "common/gen_debug.h" #include "compiler/glsl_types.h" #include "compiler/nir/nir_builder.h" #include "program/prog_parameter.h" using namespace brw; static unsigned get_lowered_simd_width(const struct gen_device_info *devinfo, const fs_inst *inst); void fs_inst::init(enum opcode opcode, uint8_t exec_size, const fs_reg &dst, const fs_reg *src, unsigned sources) { memset(this, 0, sizeof(*this)); this->src = new fs_reg[MAX2(sources, 3)]; for (unsigned i = 0; i < sources; i++) this->src[i] = src[i]; this->opcode = opcode; this->dst = dst; this->sources = sources; this->exec_size = exec_size; this->base_mrf = -1; assert(dst.file != IMM && dst.file != UNIFORM); assert(this->exec_size != 0); this->conditional_mod = BRW_CONDITIONAL_NONE; /* This will be the case for almost all instructions. */ switch (dst.file) { case VGRF: case ARF: case FIXED_GRF: case MRF: case ATTR: this->size_written = dst.component_size(exec_size); break; case BAD_FILE: this->size_written = 0; break; case IMM: case UNIFORM: unreachable("Invalid destination register file"); } this->writes_accumulator = false; } fs_inst::fs_inst() { init(BRW_OPCODE_NOP, 8, dst, NULL, 0); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size) { init(opcode, exec_size, reg_undef, NULL, 0); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst) { init(opcode, exec_size, dst, NULL, 0); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst, const fs_reg &src0) { const fs_reg src[1] = { src0 }; init(opcode, exec_size, dst, src, 1); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst, const fs_reg &src0, const fs_reg &src1) { const fs_reg src[2] = { src0, src1 }; init(opcode, exec_size, dst, src, 2); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_size, const fs_reg &dst, const fs_reg &src0, const fs_reg &src1, const fs_reg &src2) { const fs_reg src[3] = { src0, src1, src2 }; init(opcode, exec_size, dst, src, 3); } fs_inst::fs_inst(enum opcode opcode, uint8_t exec_width, const fs_reg &dst, const fs_reg src[], unsigned sources) { init(opcode, exec_width, dst, src, sources); } fs_inst::fs_inst(const fs_inst &that) { memcpy(this, &that, sizeof(that)); this->src = new fs_reg[MAX2(that.sources, 3)]; for (unsigned i = 0; i < that.sources; i++) this->src[i] = that.src[i]; } fs_inst::~fs_inst() { delete[] this->src; } void fs_inst::resize_sources(uint8_t num_sources) { if (this->sources != num_sources) { fs_reg *src = new fs_reg[MAX2(num_sources, 3)]; for (unsigned i = 0; i < MIN2(this->sources, num_sources); ++i) src[i] = this->src[i]; delete[] this->src; this->src = src; this->sources = num_sources; } } void fs_visitor::VARYING_PULL_CONSTANT_LOAD(const fs_builder &bld, const fs_reg &dst, const fs_reg &surf_index, const fs_reg &varying_offset, uint32_t const_offset) { /* We have our constant surface use a pitch of 4 bytes, so our index can * be any component of a vector, and then we load 4 contiguous * components starting from that. * * We break down the const_offset to a portion added to the variable offset * and a portion done using fs_reg::offset, which means that if you have * GLSL using something like "uniform vec4 a[20]; gl_FragColor = a[i]", * we'll temporarily generate 4 vec4 loads from offset i * 4, and CSE can * later notice that those loads are all the same and eliminate the * redundant ones. */ fs_reg vec4_offset = vgrf(glsl_type::uint_type); bld.ADD(vec4_offset, varying_offset, brw_imm_ud(const_offset & ~0xf)); /* The pull load message will load a vec4 (16 bytes). If we are loading * a double this means we are only loading 2 elements worth of data. * We also want to use a 32-bit data type for the dst of the load operation * so other parts of the driver don't get confused about the size of the * result. */ fs_reg vec4_result = bld.vgrf(BRW_REGISTER_TYPE_F, 4); fs_inst *inst = bld.emit(FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_LOGICAL, vec4_result, surf_index, vec4_offset); inst->size_written = 4 * vec4_result.component_size(inst->exec_size); if (type_sz(dst.type) == 8) { shuffle_32bit_load_result_to_64bit_data( bld, retype(vec4_result, dst.type), vec4_result, 2); } vec4_result.type = dst.type; bld.MOV(dst, offset(vec4_result, bld, (const_offset & 0xf) / type_sz(vec4_result.type))); } /** * A helper for MOV generation for fixing up broken hardware SEND dependency * handling. */ void fs_visitor::DEP_RESOLVE_MOV(const fs_builder &bld, int grf) { /* The caller always wants uncompressed to emit the minimal extra * dependencies, and to avoid having to deal with aligning its regs to 2. */ const fs_builder ubld = bld.annotate("send dependency resolve") .half(0); ubld.MOV(ubld.null_reg_f(), fs_reg(VGRF, grf, BRW_REGISTER_TYPE_F)); } bool fs_inst::equals(fs_inst *inst) const { return (opcode == inst->opcode && dst.equals(inst->dst) && src[0].equals(inst->src[0]) && src[1].equals(inst->src[1]) && src[2].equals(inst->src[2]) && saturate == inst->saturate && predicate == inst->predicate && conditional_mod == inst->conditional_mod && mlen == inst->mlen && base_mrf == inst->base_mrf && target == inst->target && eot == inst->eot && header_size == inst->header_size && shadow_compare == inst->shadow_compare && exec_size == inst->exec_size && offset == inst->offset); } bool fs_inst::is_send_from_grf() const { switch (opcode) { case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7: case SHADER_OPCODE_SHADER_TIME_ADD: case FS_OPCODE_INTERPOLATE_AT_SAMPLE: case FS_OPCODE_INTERPOLATE_AT_SHARED_OFFSET: case FS_OPCODE_INTERPOLATE_AT_PER_SLOT_OFFSET: case SHADER_OPCODE_UNTYPED_ATOMIC: case SHADER_OPCODE_UNTYPED_SURFACE_READ: case SHADER_OPCODE_UNTYPED_SURFACE_WRITE: case SHADER_OPCODE_TYPED_ATOMIC: case SHADER_OPCODE_TYPED_SURFACE_READ: case SHADER_OPCODE_TYPED_SURFACE_WRITE: case SHADER_OPCODE_URB_WRITE_SIMD8: case SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED_PER_SLOT: case SHADER_OPCODE_URB_READ_SIMD8: case SHADER_OPCODE_URB_READ_SIMD8_PER_SLOT: return true; case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD: return src[1].file == VGRF; case FS_OPCODE_FB_WRITE: case FS_OPCODE_FB_READ: return src[0].file == VGRF; default: if (is_tex()) return src[0].file == VGRF; return false; } } /** * Returns true if this instruction's sources and destinations cannot * safely be the same register. * * In most cases, a register can be written over safely by the same * instruction that is its last use. For a single instruction, the * sources are dereferenced before writing of the destination starts * (naturally). * * However, there are a few cases where this can be problematic: * * - Virtual opcodes that translate to multiple instructions in the * code generator: if src == dst and one instruction writes the * destination before a later instruction reads the source, then * src will have been clobbered. * * - SIMD16 compressed instructions with certain regioning (see below). * * The register allocator uses this information to set up conflicts between * GRF sources and the destination. */ bool fs_inst::has_source_and_destination_hazard() const { switch (opcode) { case FS_OPCODE_PACK_HALF_2x16_SPLIT: /* Multiple partial writes to the destination */ return true; default: /* The SIMD16 compressed instruction * * add(16) g4<1>F g4<8,8,1>F g6<8,8,1>F * * is actually decoded in hardware as: * * add(8) g4<1>F g4<8,8,1>F g6<8,8,1>F * add(8) g5<1>F g5<8,8,1>F g7<8,8,1>F * * Which is safe. However, if we have uniform accesses * happening, we get into trouble: * * add(8) g4<1>F g4<0,1,0>F g6<8,8,1>F * add(8) g5<1>F g4<0,1,0>F g7<8,8,1>F * * Now our destination for the first instruction overwrote the * second instruction's src0, and we get garbage for those 8 * pixels. There's a similar issue for the pre-gen6 * pixel_x/pixel_y, which are registers of 16-bit values and thus * would get stomped by the first decode as well. */ if (exec_size == 16) { for (int i = 0; i < sources; i++) { if (src[i].file == VGRF && (src[i].stride == 0 || src[i].type == BRW_REGISTER_TYPE_UW || src[i].type == BRW_REGISTER_TYPE_W || src[i].type == BRW_REGISTER_TYPE_UB || src[i].type == BRW_REGISTER_TYPE_B)) { return true; } } } return false; } } bool fs_inst::is_copy_payload(const brw::simple_allocator &grf_alloc) const { if (this->opcode != SHADER_OPCODE_LOAD_PAYLOAD) return false; fs_reg reg = this->src[0]; if (reg.file != VGRF || reg.offset != 0 || reg.stride != 1) return false; if (grf_alloc.sizes[reg.nr] * REG_SIZE != this->size_written) return false; for (int i = 0; i < this->sources; i++) { reg.type = this->src[i].type; if (!this->src[i].equals(reg)) return false; if (i < this->header_size) { reg.offset += REG_SIZE; } else { reg = horiz_offset(reg, this->exec_size); } } return true; } bool fs_inst::can_do_source_mods(const struct gen_device_info *devinfo) { if (devinfo->gen == 6 && is_math()) return false; if (is_send_from_grf()) return false; if (!backend_instruction::can_do_source_mods()) return false; return true; } bool fs_inst::can_change_types() const { return dst.type == src[0].type && !src[0].abs && !src[0].negate && !saturate && (opcode == BRW_OPCODE_MOV || (opcode == BRW_OPCODE_SEL && dst.type == src[1].type && predicate != BRW_PREDICATE_NONE && !src[1].abs && !src[1].negate)); } bool fs_inst::has_side_effects() const { return this->eot || backend_instruction::has_side_effects(); } void fs_reg::init() { memset(this, 0, sizeof(*this)); type = BRW_REGISTER_TYPE_UD; stride = 1; } /** Generic unset register constructor. */ fs_reg::fs_reg() { init(); this->file = BAD_FILE; } fs_reg::fs_reg(struct ::brw_reg reg) : backend_reg(reg) { this->offset = 0; this->stride = 1; if (this->file == IMM && (this->type != BRW_REGISTER_TYPE_V && this->type != BRW_REGISTER_TYPE_UV && this->type != BRW_REGISTER_TYPE_VF)) { this->stride = 0; } } bool fs_reg::equals(const fs_reg &r) const { return (this->backend_reg::equals(r) && stride == r.stride); } bool fs_reg::is_contiguous() const { return stride == 1; } unsigned fs_reg::component_size(unsigned width) const { const unsigned stride = ((file != ARF && file != FIXED_GRF) ? this->stride : hstride == 0 ? 0 : 1 << (hstride - 1)); return MAX2(width * stride, 1) * type_sz(type); } extern "C" int type_size_scalar(const struct glsl_type *type) { unsigned int size, i; switch (type->base_type) { case GLSL_TYPE_UINT: case GLSL_TYPE_INT: case GLSL_TYPE_FLOAT: case GLSL_TYPE_BOOL: return type->components(); case GLSL_TYPE_DOUBLE: case GLSL_TYPE_UINT64: case GLSL_TYPE_INT64: return type->components() * 2; case GLSL_TYPE_ARRAY: return type_size_scalar(type->fields.array) * type->length; case GLSL_TYPE_STRUCT: size = 0; for (i = 0; i < type->length; i++) { size += type_size_scalar(type->fields.structure[i].type); } return size; case GLSL_TYPE_SAMPLER: /* Samplers take up no register space, since they're baked in at * link time. */ return 0; case GLSL_TYPE_ATOMIC_UINT: return 0; case GLSL_TYPE_SUBROUTINE: return 1; case GLSL_TYPE_IMAGE: return BRW_IMAGE_PARAM_SIZE; case GLSL_TYPE_VOID: case GLSL_TYPE_ERROR: case GLSL_TYPE_INTERFACE: case GLSL_TYPE_FUNCTION: unreachable("not reached"); } return 0; } /** * Create a MOV to read the timestamp register. * * The caller is responsible for emitting the MOV. The return value is * the destination of the MOV, with extra parameters set. */ fs_reg fs_visitor::get_timestamp(const fs_builder &bld) { assert(devinfo->gen >= 7); fs_reg ts = fs_reg(retype(brw_vec4_reg(BRW_ARCHITECTURE_REGISTER_FILE, BRW_ARF_TIMESTAMP, 0), BRW_REGISTER_TYPE_UD)); fs_reg dst = fs_reg(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* We want to read the 3 fields we care about even if it's not enabled in * the dispatch. */ bld.group(4, 0).exec_all().MOV(dst, ts); return dst; } void fs_visitor::emit_shader_time_begin() { /* We want only the low 32 bits of the timestamp. Since it's running * at the GPU clock rate of ~1.2ghz, it will roll over every ~3 seconds, * which is plenty of time for our purposes. It is identical across the * EUs, but since it's tracking GPU core speed it will increment at a * varying rate as render P-states change. */ shader_start_time = component( get_timestamp(bld.annotate("shader time start")), 0); } void fs_visitor::emit_shader_time_end() { /* Insert our code just before the final SEND with EOT. */ exec_node *end = this->instructions.get_tail(); assert(end && ((fs_inst *) end)->eot); const fs_builder ibld = bld.annotate("shader time end") .exec_all().at(NULL, end); const fs_reg timestamp = get_timestamp(ibld); /* We only use the low 32 bits of the timestamp - see * emit_shader_time_begin()). * * We could also check if render P-states have changed (or anything * else that might disrupt timing) by setting smear to 2 and checking if * that field is != 0. */ const fs_reg shader_end_time = component(timestamp, 0); /* Check that there weren't any timestamp reset events (assuming these * were the only two timestamp reads that happened). */ const fs_reg reset = component(timestamp, 2); set_condmod(BRW_CONDITIONAL_Z, ibld.AND(ibld.null_reg_ud(), reset, brw_imm_ud(1u))); ibld.IF(BRW_PREDICATE_NORMAL); fs_reg start = shader_start_time; start.negate = true; const fs_reg diff = component(fs_reg(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD), 0); const fs_builder cbld = ibld.group(1, 0); cbld.group(1, 0).ADD(diff, start, shader_end_time); /* If there were no instructions between the two timestamp gets, the diff * is 2 cycles. Remove that overhead, so I can forget about that when * trying to determine the time taken for single instructions. */ cbld.ADD(diff, diff, brw_imm_ud(-2u)); SHADER_TIME_ADD(cbld, 0, diff); SHADER_TIME_ADD(cbld, 1, brw_imm_ud(1u)); ibld.emit(BRW_OPCODE_ELSE); SHADER_TIME_ADD(cbld, 2, brw_imm_ud(1u)); ibld.emit(BRW_OPCODE_ENDIF); } void fs_visitor::SHADER_TIME_ADD(const fs_builder &bld, int shader_time_subindex, fs_reg value) { int index = shader_time_index * 3 + shader_time_subindex; struct brw_reg offset = brw_imm_d(index * BRW_SHADER_TIME_STRIDE); fs_reg payload; if (dispatch_width == 8) payload = vgrf(glsl_type::uvec2_type); else payload = vgrf(glsl_type::uint_type); bld.emit(SHADER_OPCODE_SHADER_TIME_ADD, fs_reg(), payload, offset, value); } void fs_visitor::vfail(const char *format, va_list va) { char *msg; if (failed) return; failed = true; msg = ralloc_vasprintf(mem_ctx, format, va); msg = ralloc_asprintf(mem_ctx, "%s compile failed: %s\n", stage_abbrev, msg); this->fail_msg = msg; if (debug_enabled) { fprintf(stderr, "%s", msg); } } void fs_visitor::fail(const char *format, ...) { va_list va; va_start(va, format); vfail(format, va); va_end(va); } /** * Mark this program as impossible to compile with dispatch width greater * than n. * * During the SIMD8 compile (which happens first), we can detect and flag * things that are unsupported in SIMD16+ mode, so the compiler can skip the * SIMD16+ compile altogether. * * During a compile of dispatch width greater than n (if one happens anyway), * this just calls fail(). */ void fs_visitor::limit_dispatch_width(unsigned n, const char *msg) { if (dispatch_width > n) { fail("%s", msg); } else { max_dispatch_width = n; compiler->shader_perf_log(log_data, "Shader dispatch width limited to SIMD%d: %s", n, msg); } } /** * Returns true if the instruction has a flag that means it won't * update an entire destination register. * * For example, dead code elimination and live variable analysis want to know * when a write to a variable screens off any preceding values that were in * it. */ bool fs_inst::is_partial_write() const { return ((this->predicate && this->opcode != BRW_OPCODE_SEL) || (this->exec_size * type_sz(this->dst.type)) < 32 || !this->dst.is_contiguous() || this->dst.offset % REG_SIZE != 0); } unsigned fs_inst::components_read(unsigned i) const { /* Return zero if the source is not present. */ if (src[i].file == BAD_FILE) return 0; switch (opcode) { case FS_OPCODE_LINTERP: if (i == 0) return 2; else return 1; case FS_OPCODE_PIXEL_X: case FS_OPCODE_PIXEL_Y: assert(i == 0); return 2; case FS_OPCODE_FB_WRITE_LOGICAL: assert(src[FB_WRITE_LOGICAL_SRC_COMPONENTS].file == IMM); /* First/second FB write color. */ if (i < 2) return src[FB_WRITE_LOGICAL_SRC_COMPONENTS].ud; else return 1; case SHADER_OPCODE_TEX_LOGICAL: case SHADER_OPCODE_TXD_LOGICAL: case SHADER_OPCODE_TXF_LOGICAL: case SHADER_OPCODE_TXL_LOGICAL: case SHADER_OPCODE_TXS_LOGICAL: case FS_OPCODE_TXB_LOGICAL: case SHADER_OPCODE_TXF_CMS_LOGICAL: case SHADER_OPCODE_TXF_CMS_W_LOGICAL: case SHADER_OPCODE_TXF_UMS_LOGICAL: case SHADER_OPCODE_TXF_MCS_LOGICAL: case SHADER_OPCODE_LOD_LOGICAL: case SHADER_OPCODE_TG4_LOGICAL: case SHADER_OPCODE_TG4_OFFSET_LOGICAL: case SHADER_OPCODE_SAMPLEINFO_LOGICAL: assert(src[TEX_LOGICAL_SRC_COORD_COMPONENTS].file == IMM && src[TEX_LOGICAL_SRC_GRAD_COMPONENTS].file == IMM); /* Texture coordinates. */ if (i == TEX_LOGICAL_SRC_COORDINATE) return src[TEX_LOGICAL_SRC_COORD_COMPONENTS].ud; /* Texture derivatives. */ else if ((i == TEX_LOGICAL_SRC_LOD || i == TEX_LOGICAL_SRC_LOD2) && opcode == SHADER_OPCODE_TXD_LOGICAL) return src[TEX_LOGICAL_SRC_GRAD_COMPONENTS].ud; /* Texture offset. */ else if (i == TEX_LOGICAL_SRC_TG4_OFFSET) return 2; /* MCS */ else if (i == TEX_LOGICAL_SRC_MCS && opcode == SHADER_OPCODE_TXF_CMS_W_LOGICAL) return 2; else return 1; case SHADER_OPCODE_UNTYPED_SURFACE_READ_LOGICAL: case SHADER_OPCODE_TYPED_SURFACE_READ_LOGICAL: assert(src[3].file == IMM); /* Surface coordinates. */ if (i == 0) return src[3].ud; /* Surface operation source (ignored for reads). */ else if (i == 1) return 0; else return 1; case SHADER_OPCODE_UNTYPED_SURFACE_WRITE_LOGICAL: case SHADER_OPCODE_TYPED_SURFACE_WRITE_LOGICAL: assert(src[3].file == IMM && src[4].file == IMM); /* Surface coordinates. */ if (i == 0) return src[3].ud; /* Surface operation source. */ else if (i == 1) return src[4].ud; else return 1; case SHADER_OPCODE_UNTYPED_ATOMIC_LOGICAL: case SHADER_OPCODE_TYPED_ATOMIC_LOGICAL: { assert(src[3].file == IMM && src[4].file == IMM); const unsigned op = src[4].ud; /* Surface coordinates. */ if (i == 0) return src[3].ud; /* Surface operation source. */ else if (i == 1 && op == BRW_AOP_CMPWR) return 2; else if (i == 1 && (op == BRW_AOP_INC || op == BRW_AOP_DEC || op == BRW_AOP_PREDEC)) return 0; else return 1; } default: return 1; } } unsigned fs_inst::size_read(int arg) const { switch (opcode) { case FS_OPCODE_FB_WRITE: case FS_OPCODE_FB_READ: case SHADER_OPCODE_URB_WRITE_SIMD8: case SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED_PER_SLOT: case SHADER_OPCODE_URB_READ_SIMD8: case SHADER_OPCODE_URB_READ_SIMD8_PER_SLOT: case SHADER_OPCODE_UNTYPED_ATOMIC: case SHADER_OPCODE_UNTYPED_SURFACE_READ: case SHADER_OPCODE_UNTYPED_SURFACE_WRITE: case SHADER_OPCODE_TYPED_ATOMIC: case SHADER_OPCODE_TYPED_SURFACE_READ: case SHADER_OPCODE_TYPED_SURFACE_WRITE: case FS_OPCODE_INTERPOLATE_AT_PER_SLOT_OFFSET: if (arg == 0) return mlen * REG_SIZE; break; case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7: /* The payload is actually stored in src1 */ if (arg == 1) return mlen * REG_SIZE; break; case FS_OPCODE_LINTERP: if (arg == 1) return 16; break; case SHADER_OPCODE_LOAD_PAYLOAD: if (arg < this->header_size) return REG_SIZE; break; case CS_OPCODE_CS_TERMINATE: case SHADER_OPCODE_BARRIER: return REG_SIZE; case SHADER_OPCODE_MOV_INDIRECT: if (arg == 0) { assert(src[2].file == IMM); return src[2].ud; } break; default: if (is_tex() && arg == 0 && src[0].file == VGRF) return mlen * REG_SIZE; break; } switch (src[arg].file) { case UNIFORM: case IMM: return components_read(arg) * type_sz(src[arg].type); case BAD_FILE: case ARF: case FIXED_GRF: case VGRF: case ATTR: return components_read(arg) * src[arg].component_size(exec_size); case MRF: unreachable("MRF registers are not allowed as sources"); } return 0; } namespace { /* Return the subset of flag registers that an instruction could * potentially read or write based on the execution controls and flag * subregister number of the instruction. */ unsigned flag_mask(const fs_inst *inst) { const unsigned start = inst->flag_subreg * 16 + inst->group; const unsigned end = start + inst->exec_size; return ((1 << DIV_ROUND_UP(end, 8)) - 1) & ~((1 << (start / 8)) - 1); } unsigned bit_mask(unsigned n) { return (n >= CHAR_BIT * sizeof(bit_mask(n)) ? ~0u : (1u << n) - 1); } unsigned flag_mask(const fs_reg &r, unsigned sz) { if (r.file == ARF) { const unsigned start = (r.nr - BRW_ARF_FLAG) * 4 + r.subnr; const unsigned end = start + sz; return bit_mask(end) & ~bit_mask(start); } else { return 0; } } } unsigned fs_inst::flags_read(const gen_device_info *devinfo) const { if (predicate == BRW_PREDICATE_ALIGN1_ANYV || predicate == BRW_PREDICATE_ALIGN1_ALLV) { /* The vertical predication modes combine corresponding bits from * f0.0 and f1.0 on Gen7+, and f0.0 and f0.1 on older hardware. */ const unsigned shift = devinfo->gen >= 7 ? 4 : 2; return flag_mask(this) << shift | flag_mask(this); } else if (predicate) { return flag_mask(this); } else { unsigned mask = 0; for (int i = 0; i < sources; i++) { mask |= flag_mask(src[i], size_read(i)); } return mask; } } unsigned fs_inst::flags_written() const { if ((conditional_mod && (opcode != BRW_OPCODE_SEL && opcode != BRW_OPCODE_IF && opcode != BRW_OPCODE_WHILE)) || opcode == FS_OPCODE_MOV_DISPATCH_TO_FLAGS) { return flag_mask(this); } else { return flag_mask(dst, size_written); } } /** * Returns how many MRFs an FS opcode will write over. * * Note that this is not the 0 or 1 implied writes in an actual gen * instruction -- the FS opcodes often generate MOVs in addition. */ int fs_visitor::implied_mrf_writes(fs_inst *inst) { if (inst->mlen == 0) return 0; if (inst->base_mrf == -1) return 0; switch (inst->opcode) { case SHADER_OPCODE_RCP: case SHADER_OPCODE_RSQ: case SHADER_OPCODE_SQRT: case SHADER_OPCODE_EXP2: case SHADER_OPCODE_LOG2: case SHADER_OPCODE_SIN: case SHADER_OPCODE_COS: return 1 * dispatch_width / 8; case SHADER_OPCODE_POW: case SHADER_OPCODE_INT_QUOTIENT: case SHADER_OPCODE_INT_REMAINDER: return 2 * dispatch_width / 8; case SHADER_OPCODE_TEX: case FS_OPCODE_TXB: case SHADER_OPCODE_TXD: case SHADER_OPCODE_TXF: case SHADER_OPCODE_TXF_CMS: case SHADER_OPCODE_TXF_MCS: case SHADER_OPCODE_TG4: case SHADER_OPCODE_TG4_OFFSET: case SHADER_OPCODE_TXL: case SHADER_OPCODE_TXS: case SHADER_OPCODE_LOD: case SHADER_OPCODE_SAMPLEINFO: return 1; case FS_OPCODE_FB_WRITE: return 2; case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD: case SHADER_OPCODE_GEN4_SCRATCH_READ: return 1; case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN4: return inst->mlen; case SHADER_OPCODE_GEN4_SCRATCH_WRITE: return inst->mlen; default: unreachable("not reached"); } } fs_reg fs_visitor::vgrf(const glsl_type *const type) { int reg_width = dispatch_width / 8; return fs_reg(VGRF, alloc.allocate(type_size_scalar(type) * reg_width), brw_type_for_base_type(type)); } fs_reg::fs_reg(enum brw_reg_file file, int nr) { init(); this->file = file; this->nr = nr; this->type = BRW_REGISTER_TYPE_F; this->stride = (file == UNIFORM ? 0 : 1); } fs_reg::fs_reg(enum brw_reg_file file, int nr, enum brw_reg_type type) { init(); this->file = file; this->nr = nr; this->type = type; this->stride = (file == UNIFORM ? 0 : 1); } /* For SIMD16, we need to follow from the uniform setup of SIMD8 dispatch. * This brings in those uniform definitions */ void fs_visitor::import_uniforms(fs_visitor *v) { this->push_constant_loc = v->push_constant_loc; this->pull_constant_loc = v->pull_constant_loc; this->uniforms = v->uniforms; } void fs_visitor::emit_fragcoord_interpolation(fs_reg wpos) { assert(stage == MESA_SHADER_FRAGMENT); /* gl_FragCoord.x */ bld.MOV(wpos, this->pixel_x); wpos = offset(wpos, bld, 1); /* gl_FragCoord.y */ bld.MOV(wpos, this->pixel_y); wpos = offset(wpos, bld, 1); /* gl_FragCoord.z */ if (devinfo->gen >= 6) { bld.MOV(wpos, fs_reg(brw_vec8_grf(payload.source_depth_reg, 0))); } else { bld.emit(FS_OPCODE_LINTERP, wpos, this->delta_xy[BRW_BARYCENTRIC_PERSPECTIVE_PIXEL], interp_reg(VARYING_SLOT_POS, 2)); } wpos = offset(wpos, bld, 1); /* gl_FragCoord.w: Already set up in emit_interpolation */ bld.MOV(wpos, this->wpos_w); } enum brw_barycentric_mode brw_barycentric_mode(enum glsl_interp_mode mode, nir_intrinsic_op op) { /* Barycentric modes don't make sense for flat inputs. */ assert(mode != INTERP_MODE_FLAT); unsigned bary; switch (op) { case nir_intrinsic_load_barycentric_pixel: case nir_intrinsic_load_barycentric_at_offset: bary = BRW_BARYCENTRIC_PERSPECTIVE_PIXEL; break; case nir_intrinsic_load_barycentric_centroid: bary = BRW_BARYCENTRIC_PERSPECTIVE_CENTROID; break; case nir_intrinsic_load_barycentric_sample: case nir_intrinsic_load_barycentric_at_sample: bary = BRW_BARYCENTRIC_PERSPECTIVE_SAMPLE; break; default: unreachable("invalid intrinsic"); } if (mode == INTERP_MODE_NOPERSPECTIVE) bary += 3; return (enum brw_barycentric_mode) bary; } /** * Turn one of the two CENTROID barycentric modes into PIXEL mode. */ static enum brw_barycentric_mode centroid_to_pixel(enum brw_barycentric_mode bary) { assert(bary == BRW_BARYCENTRIC_PERSPECTIVE_CENTROID || bary == BRW_BARYCENTRIC_NONPERSPECTIVE_CENTROID); return (enum brw_barycentric_mode) ((unsigned) bary - 1); } fs_reg * fs_visitor::emit_frontfacing_interpolation() { fs_reg *reg = new(this->mem_ctx) fs_reg(vgrf(glsl_type::bool_type)); if (devinfo->gen >= 6) { /* Bit 15 of g0.0 is 0 if the polygon is front facing. We want to create * a boolean result from this (~0/true or 0/false). * * We can use the fact that bit 15 is the MSB of g0.0:W to accomplish * this task in only one instruction: * - a negation source modifier will flip the bit; and * - a W -> D type conversion will sign extend the bit into the high * word of the destination. * * An ASR 15 fills the low word of the destination. */ fs_reg g0 = fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_W)); g0.negate = true; bld.ASR(*reg, g0, brw_imm_d(15)); } else { /* Bit 31 of g1.6 is 0 if the polygon is front facing. We want to create * a boolean result from this (1/true or 0/false). * * Like in the above case, since the bit is the MSB of g1.6:UD we can use * the negation source modifier to flip it. Unfortunately the SHR * instruction only operates on UD (or D with an abs source modifier) * sources without negation. * * Instead, use ASR (which will give ~0/true or 0/false). */ fs_reg g1_6 = fs_reg(retype(brw_vec1_grf(1, 6), BRW_REGISTER_TYPE_D)); g1_6.negate = true; bld.ASR(*reg, g1_6, brw_imm_d(31)); } return reg; } void fs_visitor::compute_sample_position(fs_reg dst, fs_reg int_sample_pos) { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *wm_prog_data = brw_wm_prog_data(this->prog_data); assert(dst.type == BRW_REGISTER_TYPE_F); if (wm_prog_data->persample_dispatch) { /* Convert int_sample_pos to floating point */ bld.MOV(dst, int_sample_pos); /* Scale to the range [0, 1] */ bld.MUL(dst, dst, brw_imm_f(1 / 16.0f)); } else { /* From ARB_sample_shading specification: * "When rendering to a non-multisample buffer, or if multisample * rasterization is disabled, gl_SamplePosition will always be * (0.5, 0.5). */ bld.MOV(dst, brw_imm_f(0.5f)); } } fs_reg * fs_visitor::emit_samplepos_setup() { assert(devinfo->gen >= 6); const fs_builder abld = bld.annotate("compute sample position"); fs_reg *reg = new(this->mem_ctx) fs_reg(vgrf(glsl_type::vec2_type)); fs_reg pos = *reg; fs_reg int_sample_x = vgrf(glsl_type::int_type); fs_reg int_sample_y = vgrf(glsl_type::int_type); /* WM will be run in MSDISPMODE_PERSAMPLE. So, only one of SIMD8 or SIMD16 * mode will be enabled. * * From the Ivy Bridge PRM, volume 2 part 1, page 344: * R31.1:0 Position Offset X/Y for Slot[3:0] * R31.3:2 Position Offset X/Y for Slot[7:4] * ..... * * The X, Y sample positions come in as bytes in thread payload. So, read * the positions using vstride=16, width=8, hstride=2. */ struct brw_reg sample_pos_reg = stride(retype(brw_vec1_grf(payload.sample_pos_reg, 0), BRW_REGISTER_TYPE_B), 16, 8, 2); if (dispatch_width == 8) { abld.MOV(int_sample_x, fs_reg(sample_pos_reg)); } else { abld.half(0).MOV(half(int_sample_x, 0), fs_reg(sample_pos_reg)); abld.half(1).MOV(half(int_sample_x, 1), fs_reg(suboffset(sample_pos_reg, 16))); } /* Compute gl_SamplePosition.x */ compute_sample_position(pos, int_sample_x); pos = offset(pos, abld, 1); if (dispatch_width == 8) { abld.MOV(int_sample_y, fs_reg(suboffset(sample_pos_reg, 1))); } else { abld.half(0).MOV(half(int_sample_y, 0), fs_reg(suboffset(sample_pos_reg, 1))); abld.half(1).MOV(half(int_sample_y, 1), fs_reg(suboffset(sample_pos_reg, 17))); } /* Compute gl_SamplePosition.y */ compute_sample_position(pos, int_sample_y); return reg; } fs_reg * fs_visitor::emit_sampleid_setup() { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; assert(devinfo->gen >= 6); const fs_builder abld = bld.annotate("compute sample id"); fs_reg *reg = new(this->mem_ctx) fs_reg(vgrf(glsl_type::int_type)); if (!key->multisample_fbo) { /* As per GL_ARB_sample_shading specification: * "When rendering to a non-multisample buffer, or if multisample * rasterization is disabled, gl_SampleID will always be zero." */ abld.MOV(*reg, brw_imm_d(0)); } else if (devinfo->gen >= 8) { /* Sample ID comes in as 4-bit numbers in g1.0: * * 15:12 Slot 3 SampleID (only used in SIMD16) * 11:8 Slot 2 SampleID (only used in SIMD16) * 7:4 Slot 1 SampleID * 3:0 Slot 0 SampleID * * Each slot corresponds to four channels, so we want to replicate each * half-byte value to 4 channels in a row: * * dst+0: .7 .6 .5 .4 .3 .2 .1 .0 * 7:4 7:4 7:4 7:4 3:0 3:0 3:0 3:0 * * dst+1: .7 .6 .5 .4 .3 .2 .1 .0 (if SIMD16) * 15:12 15:12 15:12 15:12 11:8 11:8 11:8 11:8 * * First, we read g1.0 with a <1,8,0>UB region, causing the first 8 * channels to read the first byte (7:0), and the second group of 8 * channels to read the second byte (15:8). Then, we shift right by * a vector immediate of <4, 4, 4, 4, 0, 0, 0, 0>, moving the slot 1 / 3 * values into place. Finally, we AND with 0xf to keep the low nibble. * * shr(16) tmp<1>W g1.0<1,8,0>B 0x44440000:V * and(16) dst<1>D tmp<8,8,1>W 0xf:W * * TODO: These payload bits exist on Gen7 too, but they appear to always * be zero, so this code fails to work. We should find out why. */ fs_reg tmp(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_W); abld.SHR(tmp, fs_reg(stride(retype(brw_vec1_grf(1, 0), BRW_REGISTER_TYPE_B), 1, 8, 0)), brw_imm_v(0x44440000)); abld.AND(*reg, tmp, brw_imm_w(0xf)); } else { const fs_reg t1 = component(fs_reg(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_D), 0); const fs_reg t2(VGRF, alloc.allocate(1), BRW_REGISTER_TYPE_W); /* The PS will be run in MSDISPMODE_PERSAMPLE. For example with * 8x multisampling, subspan 0 will represent sample N (where N * is 0, 2, 4 or 6), subspan 1 will represent sample 1, 3, 5 or * 7. We can find the value of N by looking at R0.0 bits 7:6 * ("Starting Sample Pair Index (SSPI)") and multiplying by two * (since samples are always delivered in pairs). That is, we * compute 2*((R0.0 & 0xc0) >> 6) == (R0.0 & 0xc0) >> 5. Then * we need to add N to the sequence (0, 0, 0, 0, 1, 1, 1, 1) in * case of SIMD8 and sequence (0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, * 2, 3, 3, 3, 3) in case of SIMD16. We compute this sequence by * populating a temporary variable with the sequence (0, 1, 2, 3), * and then reading from it using vstride=1, width=4, hstride=0. * These computations hold good for 4x multisampling as well. * * For 2x MSAA and SIMD16, we want to use the sequence (0, 1, 0, 1): * the first four slots are sample 0 of subspan 0; the next four * are sample 1 of subspan 0; the third group is sample 0 of * subspan 1, and finally sample 1 of subspan 1. */ /* SKL+ has an extra bit for the Starting Sample Pair Index to * accomodate 16x MSAA. */ abld.exec_all().group(1, 0) .AND(t1, fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_D)), brw_imm_ud(0xc0)); abld.exec_all().group(1, 0).SHR(t1, t1, brw_imm_d(5)); /* This works for both SIMD8 and SIMD16 */ abld.exec_all().group(4, 0).MOV(t2, brw_imm_v(0x3210)); /* This special instruction takes care of setting vstride=1, * width=4, hstride=0 of t2 during an ADD instruction. */ abld.emit(FS_OPCODE_SET_SAMPLE_ID, *reg, t1, t2); } return reg; } fs_reg * fs_visitor::emit_samplemaskin_setup() { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *wm_prog_data = brw_wm_prog_data(this->prog_data); assert(devinfo->gen >= 6); fs_reg *reg = new(this->mem_ctx) fs_reg(vgrf(glsl_type::int_type)); fs_reg coverage_mask(retype(brw_vec8_grf(payload.sample_mask_in_reg, 0), BRW_REGISTER_TYPE_D)); if (wm_prog_data->persample_dispatch) { /* gl_SampleMaskIn[] comes from two sources: the input coverage mask, * and a mask representing which sample is being processed by the * current shader invocation. * * From the OES_sample_variables specification: * "When per-sample shading is active due to the use of a fragment input * qualified by "sample" or due to the use of the gl_SampleID or * gl_SamplePosition variables, only the bit for the current sample is * set in gl_SampleMaskIn." */ const fs_builder abld = bld.annotate("compute gl_SampleMaskIn"); if (nir_system_values[SYSTEM_VALUE_SAMPLE_ID].file == BAD_FILE) nir_system_values[SYSTEM_VALUE_SAMPLE_ID] = *emit_sampleid_setup(); fs_reg one = vgrf(glsl_type::int_type); fs_reg enabled_mask = vgrf(glsl_type::int_type); abld.MOV(one, brw_imm_d(1)); abld.SHL(enabled_mask, one, nir_system_values[SYSTEM_VALUE_SAMPLE_ID]); abld.AND(*reg, enabled_mask, coverage_mask); } else { /* In per-pixel mode, the coverage mask is sufficient. */ *reg = coverage_mask; } return reg; } fs_reg fs_visitor::resolve_source_modifiers(const fs_reg &src) { if (!src.abs && !src.negate) return src; fs_reg temp = bld.vgrf(src.type); bld.MOV(temp, src); return temp; } void fs_visitor::emit_discard_jump() { assert(brw_wm_prog_data(this->prog_data)->uses_kill); /* For performance, after a discard, jump to the end of the * shader if all relevant channels have been discarded. */ fs_inst *discard_jump = bld.emit(FS_OPCODE_DISCARD_JUMP); discard_jump->flag_subreg = 1; discard_jump->predicate = BRW_PREDICATE_ALIGN1_ANY4H; discard_jump->predicate_inverse = true; } void fs_visitor::emit_gs_thread_end() { assert(stage == MESA_SHADER_GEOMETRY); struct brw_gs_prog_data *gs_prog_data = brw_gs_prog_data(prog_data); if (gs_compile->control_data_header_size_bits > 0) { emit_gs_control_data_bits(this->final_gs_vertex_count); } const fs_builder abld = bld.annotate("thread end"); fs_inst *inst; if (gs_prog_data->static_vertex_count != -1) { foreach_in_list_reverse(fs_inst, prev, &this->instructions) { if (prev->opcode == SHADER_OPCODE_URB_WRITE_SIMD8 || prev->opcode == SHADER_OPCODE_URB_WRITE_SIMD8_MASKED || prev->opcode == SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT || prev->opcode == SHADER_OPCODE_URB_WRITE_SIMD8_MASKED_PER_SLOT) { prev->eot = true; /* Delete now dead instructions. */ foreach_in_list_reverse_safe(exec_node, dead, &this->instructions) { if (dead == prev) break; dead->remove(); } return; } else if (prev->is_control_flow() || prev->has_side_effects()) { break; } } fs_reg hdr = abld.vgrf(BRW_REGISTER_TYPE_UD, 1); abld.MOV(hdr, fs_reg(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD))); inst = abld.emit(SHADER_OPCODE_URB_WRITE_SIMD8, reg_undef, hdr); inst->mlen = 1; } else { fs_reg payload = abld.vgrf(BRW_REGISTER_TYPE_UD, 2); fs_reg *sources = ralloc_array(mem_ctx, fs_reg, 2); sources[0] = fs_reg(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD)); sources[1] = this->final_gs_vertex_count; abld.LOAD_PAYLOAD(payload, sources, 2, 2); inst = abld.emit(SHADER_OPCODE_URB_WRITE_SIMD8, reg_undef, payload); inst->mlen = 2; } inst->eot = true; inst->offset = 0; } void fs_visitor::assign_curb_setup() { unsigned uniform_push_length = DIV_ROUND_UP(stage_prog_data->nr_params, 8); unsigned ubo_push_length = 0; unsigned ubo_push_start[4]; for (int i = 0; i < 4; i++) { ubo_push_start[i] = 8 * (ubo_push_length + uniform_push_length); ubo_push_length += stage_prog_data->ubo_ranges[i].length; } prog_data->curb_read_length = uniform_push_length + ubo_push_length; /* Map the offsets in the UNIFORM file to fixed HW regs. */ foreach_block_and_inst(block, fs_inst, inst, cfg) { for (unsigned int i = 0; i < inst->sources; i++) { if (inst->src[i].file == UNIFORM) { int uniform_nr = inst->src[i].nr + inst->src[i].offset / 4; int constant_nr; if (inst->src[i].nr >= UBO_START) { /* constant_nr is in 32-bit units, the rest are in bytes */ constant_nr = ubo_push_start[inst->src[i].nr - UBO_START] + inst->src[i].offset / 4; } else if (uniform_nr >= 0 && uniform_nr < (int) uniforms) { constant_nr = push_constant_loc[uniform_nr]; } else { /* Section 5.11 of the OpenGL 4.1 spec says: * "Out-of-bounds reads return undefined values, which include * values from other variables of the active program or zero." * Just return the first push constant. */ constant_nr = 0; } struct brw_reg brw_reg = brw_vec1_grf(payload.num_regs + constant_nr / 8, constant_nr % 8); brw_reg.abs = inst->src[i].abs; brw_reg.negate = inst->src[i].negate; assert(inst->src[i].stride == 0); inst->src[i] = byte_offset( retype(brw_reg, inst->src[i].type), inst->src[i].offset % 4); } } } /* This may be updated in assign_urb_setup or assign_vs_urb_setup. */ this->first_non_payload_grf = payload.num_regs + prog_data->curb_read_length; } void fs_visitor::calculate_urb_setup() { 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; memset(prog_data->urb_setup, -1, sizeof(prog_data->urb_setup[0]) * VARYING_SLOT_MAX); int urb_next = 0; /* Figure out where each of the incoming setup attributes lands. */ if (devinfo->gen >= 6) { if (_mesa_bitcount_64(nir->info.inputs_read & BRW_FS_VARYING_INPUT_MASK) <= 16) { /* The SF/SBE pipeline stage can do arbitrary rearrangement of the * first 16 varying inputs, so we can put them wherever we want. * Just put them in order. * * This is useful because it means that (a) inputs not used by the * fragment shader won't take up valuable register space, and (b) we * won't have to recompile the fragment shader if it gets paired with * a different vertex (or geometry) shader. */ for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) { if (nir->info.inputs_read & BRW_FS_VARYING_INPUT_MASK & BITFIELD64_BIT(i)) { prog_data->urb_setup[i] = urb_next++; } } } else { bool include_vue_header = nir->info.inputs_read & (VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT); /* We have enough input varyings that the SF/SBE pipeline stage can't * arbitrarily rearrange them to suit our whim; we have to put them * in an order that matches the output of the previous pipeline stage * (geometry or vertex shader). */ struct brw_vue_map prev_stage_vue_map; brw_compute_vue_map(devinfo, &prev_stage_vue_map, key->input_slots_valid, nir->info.separate_shader); int first_slot = include_vue_header ? 0 : 2 * BRW_SF_URB_ENTRY_READ_OFFSET; assert(prev_stage_vue_map.num_slots <= first_slot + 32); for (int slot = first_slot; slot < prev_stage_vue_map.num_slots; slot++) { int varying = prev_stage_vue_map.slot_to_varying[slot]; if (varying != BRW_VARYING_SLOT_PAD && (nir->info.inputs_read & BRW_FS_VARYING_INPUT_MASK & BITFIELD64_BIT(varying))) { prog_data->urb_setup[varying] = slot - first_slot; } } urb_next = prev_stage_vue_map.num_slots - first_slot; } } else { /* FINISHME: The sf doesn't map VS->FS inputs for us very well. */ for (unsigned int i = 0; i < VARYING_SLOT_MAX; i++) { /* Point size is packed into the header, not as a general attribute */ if (i == VARYING_SLOT_PSIZ) continue; if (key->input_slots_valid & BITFIELD64_BIT(i)) { /* The back color slot is skipped when the front color is * also written to. In addition, some slots can be * written in the vertex shader and not read in the * fragment shader. So the register number must always be * incremented, mapped or not. */ if (_mesa_varying_slot_in_fs((gl_varying_slot) i)) prog_data->urb_setup[i] = urb_next; urb_next++; } } /* * It's a FS only attribute, and we did interpolation for this attribute * in SF thread. So, count it here, too. * * See compile_sf_prog() for more info. */ if (nir->info.inputs_read & BITFIELD64_BIT(VARYING_SLOT_PNTC)) prog_data->urb_setup[VARYING_SLOT_PNTC] = urb_next++; } prog_data->num_varying_inputs = urb_next; } void fs_visitor::assign_urb_setup() { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *prog_data = brw_wm_prog_data(this->prog_data); int urb_start = payload.num_regs + prog_data->base.curb_read_length; /* Offset all the urb_setup[] index by the actual position of the * setup regs, now that the location of the constants has been chosen. */ foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->opcode == FS_OPCODE_LINTERP) { assert(inst->src[1].file == FIXED_GRF); inst->src[1].nr += urb_start; } if (inst->opcode == FS_OPCODE_CINTERP) { assert(inst->src[0].file == FIXED_GRF); inst->src[0].nr += urb_start; } } /* Each attribute is 4 setup channels, each of which is half a reg. */ this->first_non_payload_grf += prog_data->num_varying_inputs * 2; } void fs_visitor::convert_attr_sources_to_hw_regs(fs_inst *inst) { for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == ATTR) { int grf = payload.num_regs + prog_data->curb_read_length + inst->src[i].nr + inst->src[i].offset / REG_SIZE; /* As explained at brw_reg_from_fs_reg, From the Haswell PRM: * * VertStride must be used to cross GRF register boundaries. This * rule implies that elements within a 'Width' cannot cross GRF * boundaries. * * So, for registers that are large enough, we have to split the exec * size in two and trust the compression state to sort it out. */ unsigned total_size = inst->exec_size * inst->src[i].stride * type_sz(inst->src[i].type); assert(total_size <= 2 * REG_SIZE); const unsigned exec_size = (total_size <= REG_SIZE) ? inst->exec_size : inst->exec_size / 2; unsigned width = inst->src[i].stride == 0 ? 1 : exec_size; struct brw_reg reg = stride(byte_offset(retype(brw_vec8_grf(grf, 0), inst->src[i].type), inst->src[i].offset % REG_SIZE), exec_size * inst->src[i].stride, width, inst->src[i].stride); reg.abs = inst->src[i].abs; reg.negate = inst->src[i].negate; inst->src[i] = reg; } } } void fs_visitor::assign_vs_urb_setup() { struct brw_vs_prog_data *vs_prog_data = brw_vs_prog_data(prog_data); assert(stage == MESA_SHADER_VERTEX); /* Each attribute is 4 regs. */ this->first_non_payload_grf += 4 * vs_prog_data->nr_attribute_slots; assert(vs_prog_data->base.urb_read_length <= 15); /* Rewrite all ATTR file references to the hw grf that they land in. */ foreach_block_and_inst(block, fs_inst, inst, cfg) { convert_attr_sources_to_hw_regs(inst); } } void fs_visitor::assign_tcs_single_patch_urb_setup() { assert(stage == MESA_SHADER_TESS_CTRL); /* Rewrite all ATTR file references to HW_REGs. */ foreach_block_and_inst(block, fs_inst, inst, cfg) { convert_attr_sources_to_hw_regs(inst); } } void fs_visitor::assign_tes_urb_setup() { assert(stage == MESA_SHADER_TESS_EVAL); struct brw_vue_prog_data *vue_prog_data = brw_vue_prog_data(prog_data); first_non_payload_grf += 8 * vue_prog_data->urb_read_length; /* Rewrite all ATTR file references to HW_REGs. */ foreach_block_and_inst(block, fs_inst, inst, cfg) { convert_attr_sources_to_hw_regs(inst); } } void fs_visitor::assign_gs_urb_setup() { assert(stage == MESA_SHADER_GEOMETRY); struct brw_vue_prog_data *vue_prog_data = brw_vue_prog_data(prog_data); first_non_payload_grf += 8 * vue_prog_data->urb_read_length * nir->info.gs.vertices_in; foreach_block_and_inst(block, fs_inst, inst, cfg) { /* Rewrite all ATTR file references to GRFs. */ convert_attr_sources_to_hw_regs(inst); } } /** * Split large virtual GRFs into separate components if we can. * * This is mostly duplicated with what brw_fs_vector_splitting does, * but that's really conservative because it's afraid of doing * splitting that doesn't result in real progress after the rest of * the optimization phases, which would cause infinite looping in * optimization. We can do it once here, safely. This also has the * opportunity to split interpolated values, or maybe even uniforms, * which we don't have at the IR level. * * We want to split, because virtual GRFs are what we register * allocate and spill (due to contiguousness requirements for some * instructions), and they're what we naturally generate in the * codegen process, but most virtual GRFs don't actually need to be * contiguous sets of GRFs. If we split, we'll end up with reduced * live intervals and better dead code elimination and coalescing. */ void fs_visitor::split_virtual_grfs() { /* Compact the register file so we eliminate dead vgrfs. This * only defines split points for live registers, so if we have * too large dead registers they will hit assertions later. */ compact_virtual_grfs(); int num_vars = this->alloc.count; /* Count the total number of registers */ int reg_count = 0; int vgrf_to_reg[num_vars]; for (int i = 0; i < num_vars; i++) { vgrf_to_reg[i] = reg_count; reg_count += alloc.sizes[i]; } /* An array of "split points". For each register slot, this indicates * if this slot can be separated from the previous slot. Every time an * instruction uses multiple elements of a register (as a source or * destination), we mark the used slots as inseparable. Then we go * through and split the registers into the smallest pieces we can. */ bool split_points[reg_count]; memset(split_points, 0, sizeof(split_points)); /* Mark all used registers as fully splittable */ foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->dst.file == VGRF) { int reg = vgrf_to_reg[inst->dst.nr]; for (unsigned j = 1; j < this->alloc.sizes[inst->dst.nr]; j++) split_points[reg + j] = true; } for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF) { int reg = vgrf_to_reg[inst->src[i].nr]; for (unsigned j = 1; j < this->alloc.sizes[inst->src[i].nr]; j++) split_points[reg + j] = true; } } } foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->dst.file == VGRF) { int reg = vgrf_to_reg[inst->dst.nr] + inst->dst.offset / REG_SIZE; for (unsigned j = 1; j < regs_written(inst); j++) split_points[reg + j] = false; } for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF) { int reg = vgrf_to_reg[inst->src[i].nr] + inst->src[i].offset / REG_SIZE; for (unsigned j = 1; j < regs_read(inst, i); j++) split_points[reg + j] = false; } } } int new_virtual_grf[reg_count]; int new_reg_offset[reg_count]; int reg = 0; for (int i = 0; i < num_vars; i++) { /* The first one should always be 0 as a quick sanity check. */ assert(split_points[reg] == false); /* j = 0 case */ new_reg_offset[reg] = 0; reg++; int offset = 1; /* j > 0 case */ for (unsigned j = 1; j < alloc.sizes[i]; j++) { /* If this is a split point, reset the offset to 0 and allocate a * new virtual GRF for the previous offset many registers */ if (split_points[reg]) { assert(offset <= MAX_VGRF_SIZE); int grf = alloc.allocate(offset); for (int k = reg - offset; k < reg; k++) new_virtual_grf[k] = grf; offset = 0; } new_reg_offset[reg] = offset; offset++; reg++; } /* The last one gets the original register number */ assert(offset <= MAX_VGRF_SIZE); alloc.sizes[i] = offset; for (int k = reg - offset; k < reg; k++) new_virtual_grf[k] = i; } assert(reg == reg_count); foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->dst.file == VGRF) { reg = vgrf_to_reg[inst->dst.nr] + inst->dst.offset / REG_SIZE; inst->dst.nr = new_virtual_grf[reg]; inst->dst.offset = new_reg_offset[reg] * REG_SIZE + inst->dst.offset % REG_SIZE; assert((unsigned)new_reg_offset[reg] < alloc.sizes[new_virtual_grf[reg]]); } for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF) { reg = vgrf_to_reg[inst->src[i].nr] + inst->src[i].offset / REG_SIZE; inst->src[i].nr = new_virtual_grf[reg]; inst->src[i].offset = new_reg_offset[reg] * REG_SIZE + inst->src[i].offset % REG_SIZE; assert((unsigned)new_reg_offset[reg] < alloc.sizes[new_virtual_grf[reg]]); } } } invalidate_live_intervals(); } /** * Remove unused virtual GRFs and compact the virtual_grf_* arrays. * * During code generation, we create tons of temporary variables, many of * which get immediately killed and are never used again. Yet, in later * optimization and analysis passes, such as compute_live_intervals, we need * to loop over all the virtual GRFs. Compacting them can save a lot of * overhead. */ bool fs_visitor::compact_virtual_grfs() { bool progress = false; int remap_table[this->alloc.count]; memset(remap_table, -1, sizeof(remap_table)); /* Mark which virtual GRFs are used. */ foreach_block_and_inst(block, const fs_inst, inst, cfg) { if (inst->dst.file == VGRF) remap_table[inst->dst.nr] = 0; for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF) remap_table[inst->src[i].nr] = 0; } } /* Compact the GRF arrays. */ int new_index = 0; for (unsigned i = 0; i < this->alloc.count; i++) { if (remap_table[i] == -1) { /* We just found an unused register. This means that we are * actually going to compact something. */ progress = true; } else { remap_table[i] = new_index; alloc.sizes[new_index] = alloc.sizes[i]; invalidate_live_intervals(); ++new_index; } } this->alloc.count = new_index; /* Patch all the instructions to use the newly renumbered registers */ foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->dst.file == VGRF) inst->dst.nr = remap_table[inst->dst.nr]; for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF) inst->src[i].nr = remap_table[inst->src[i].nr]; } } /* Patch all the references to delta_xy, since they're used in register * allocation. If they're unused, switch them to BAD_FILE so we don't * think some random VGRF is delta_xy. */ for (unsigned i = 0; i < ARRAY_SIZE(delta_xy); i++) { if (delta_xy[i].file == VGRF) { if (remap_table[delta_xy[i].nr] != -1) { delta_xy[i].nr = remap_table[delta_xy[i].nr]; } else { delta_xy[i].file = BAD_FILE; } } } return progress; } static void set_push_pull_constant_loc(unsigned uniform, int *chunk_start, unsigned *max_chunk_bitsize, bool contiguous, unsigned bitsize, const unsigned target_bitsize, int *push_constant_loc, int *pull_constant_loc, unsigned *num_push_constants, unsigned *num_pull_constants, const unsigned max_push_components, const unsigned max_chunk_size, struct brw_stage_prog_data *stage_prog_data) { /* This is the first live uniform in the chunk */ if (*chunk_start < 0) *chunk_start = uniform; /* Keep track of the maximum bit size access in contiguous uniforms */ *max_chunk_bitsize = MAX2(*max_chunk_bitsize, bitsize); /* If this element does not need to be contiguous with the next, we * split at this point and everything between chunk_start and u forms a * single chunk. */ if (!contiguous) { /* If bitsize doesn't match the target one, skip it */ if (*max_chunk_bitsize != target_bitsize) { /* FIXME: right now we only support 32 and 64-bit accesses */ assert(*max_chunk_bitsize == 4 || *max_chunk_bitsize == 8); *max_chunk_bitsize = 0; *chunk_start = -1; return; } unsigned chunk_size = uniform - *chunk_start + 1; /* Decide whether we should push or pull this parameter. In the * Vulkan driver, push constants are explicitly exposed via the API * so we push everything. In GL, we only push small arrays. */ if (stage_prog_data->pull_param == NULL || (*num_push_constants + chunk_size <= max_push_components && chunk_size <= max_chunk_size)) { assert(*num_push_constants + chunk_size <= max_push_components); for (unsigned j = *chunk_start; j <= uniform; j++) push_constant_loc[j] = (*num_push_constants)++; } else { for (unsigned j = *chunk_start; j <= uniform; j++) pull_constant_loc[j] = (*num_pull_constants)++; } *max_chunk_bitsize = 0; *chunk_start = -1; } } /** * Assign UNIFORM file registers to either push constants or pull constants. * * We allow a fragment shader to have more than the specified minimum * maximum number of fragment shader uniform components (64). If * there are too many of these, they'd fill up all of register space. * So, this will push some of them out to the pull constant buffer and * update the program to load them. */ void fs_visitor::assign_constant_locations() { /* Only the first compile gets to decide on locations. */ if (dispatch_width != min_dispatch_width) return; bool is_live[uniforms]; memset(is_live, 0, sizeof(is_live)); unsigned bitsize_access[uniforms]; memset(bitsize_access, 0, sizeof(bitsize_access)); /* For each uniform slot, a value of true indicates that the given slot and * the next slot must remain contiguous. This is used to keep us from * splitting arrays apart. */ bool contiguous[uniforms]; memset(contiguous, 0, sizeof(contiguous)); int thread_local_id_index = (stage == MESA_SHADER_COMPUTE) ? brw_cs_prog_data(stage_prog_data)->thread_local_id_index : -1; /* First, we walk through the instructions and do two things: * * 1) Figure out which uniforms are live. * * 2) Mark any indirectly used ranges of registers as contiguous. * * Note that we don't move constant-indexed accesses to arrays. No * testing has been done of the performance impact of this choice. */ foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { for (int i = 0 ; i < inst->sources; i++) { if (inst->src[i].file != UNIFORM) continue; int constant_nr = inst->src[i].nr + inst->src[i].offset / 4; if (inst->opcode == SHADER_OPCODE_MOV_INDIRECT && i == 0) { assert(inst->src[2].ud % 4 == 0); unsigned last = constant_nr + (inst->src[2].ud / 4) - 1; assert(last < uniforms); for (unsigned j = constant_nr; j < last; j++) { is_live[j] = true; contiguous[j] = true; bitsize_access[j] = MAX2(bitsize_access[j], type_sz(inst->src[i].type)); } is_live[last] = true; bitsize_access[last] = MAX2(bitsize_access[last], type_sz(inst->src[i].type)); } else { if (constant_nr >= 0 && constant_nr < (int) uniforms) { int regs_read = inst->components_read(i) * type_sz(inst->src[i].type) / 4; for (int j = 0; j < regs_read; j++) { is_live[constant_nr + j] = true; bitsize_access[constant_nr + j] = MAX2(bitsize_access[constant_nr + j], type_sz(inst->src[i].type)); } } } } } if (thread_local_id_index >= 0 && !is_live[thread_local_id_index]) thread_local_id_index = -1; /* Only allow 16 registers (128 uniform components) as push constants. * * Just demote the end of the list. We could probably do better * here, demoting things that are rarely used in the program first. * * If changing this value, note the limitation about total_regs in * brw_curbe.c. */ unsigned int max_push_components = 16 * 8; if (thread_local_id_index >= 0) max_push_components--; /* Save a slot for the thread ID */ /* We push small arrays, but no bigger than 16 floats. This is big enough * for a vec4 but hopefully not large enough to push out other stuff. We * should probably use a better heuristic at some point. */ const unsigned int max_chunk_size = 16; unsigned int num_push_constants = 0; unsigned int num_pull_constants = 0; push_constant_loc = ralloc_array(mem_ctx, int, uniforms); pull_constant_loc = ralloc_array(mem_ctx, int, uniforms); /* Default to -1 meaning no location */ memset(push_constant_loc, -1, uniforms * sizeof(*push_constant_loc)); memset(pull_constant_loc, -1, uniforms * sizeof(*pull_constant_loc)); int chunk_start = -1; unsigned max_chunk_bitsize = 0; /* First push 64-bit uniforms to ensure they are properly aligned */ const unsigned uniform_64_bit_size = type_sz(BRW_REGISTER_TYPE_DF); for (unsigned u = 0; u < uniforms; u++) { if (!is_live[u]) continue; set_push_pull_constant_loc(u, &chunk_start, &max_chunk_bitsize, contiguous[u], bitsize_access[u], uniform_64_bit_size, push_constant_loc, pull_constant_loc, &num_push_constants, &num_pull_constants, max_push_components, max_chunk_size, stage_prog_data); } /* Then push the rest of uniforms */ const unsigned uniform_32_bit_size = type_sz(BRW_REGISTER_TYPE_F); for (unsigned u = 0; u < uniforms; u++) { if (!is_live[u]) continue; /* Skip thread_local_id_index to put it in the last push register. */ if (thread_local_id_index == (int)u) continue; set_push_pull_constant_loc(u, &chunk_start, &max_chunk_bitsize, contiguous[u], bitsize_access[u], uniform_32_bit_size, push_constant_loc, pull_constant_loc, &num_push_constants, &num_pull_constants, max_push_components, max_chunk_size, stage_prog_data); } /* Add the CS local thread ID uniform at the end of the push constants */ if (thread_local_id_index >= 0) push_constant_loc[thread_local_id_index] = num_push_constants++; /* As the uniforms are going to be reordered, take the data from a temporary * copy of the original param[]. */ gl_constant_value **param = ralloc_array(NULL, gl_constant_value*, stage_prog_data->nr_params); memcpy(param, stage_prog_data->param, sizeof(gl_constant_value*) * stage_prog_data->nr_params); stage_prog_data->nr_params = num_push_constants; stage_prog_data->nr_pull_params = num_pull_constants; /* Now that we know how many regular uniforms we'll push, reduce the * UBO push ranges so we don't exceed the 3DSTATE_CONSTANT limits. */ unsigned push_length = DIV_ROUND_UP(stage_prog_data->nr_params, 8); for (int i = 0; i < 4; i++) { struct brw_ubo_range *range = &prog_data->ubo_ranges[i]; if (push_length + range->length > 64) range->length = 64 - push_length; push_length += range->length; } assert(push_length <= 64); /* Up until now, the param[] array has been indexed by reg + offset * of UNIFORM registers. Move pull constants into pull_param[] and * condense param[] to only contain the uniforms we chose to push. * * NOTE: Because we are condensing the params[] array, we know that * push_constant_loc[i] <= i and we can do it in one smooth loop without * having to make a copy. */ int new_thread_local_id_index = -1; for (unsigned int i = 0; i < uniforms; i++) { const gl_constant_value *value = param[i]; if (pull_constant_loc[i] != -1) { stage_prog_data->pull_param[pull_constant_loc[i]] = value; } else if (push_constant_loc[i] != -1) { stage_prog_data->param[push_constant_loc[i]] = value; if (thread_local_id_index == (int)i) new_thread_local_id_index = push_constant_loc[i]; } } ralloc_free(param); if (stage == MESA_SHADER_COMPUTE) brw_cs_prog_data(stage_prog_data)->thread_local_id_index = new_thread_local_id_index; } bool fs_visitor::get_pull_locs(const fs_reg &src, unsigned *out_surf_index, unsigned *out_pull_index) { assert(src.file == UNIFORM); if (src.nr >= UBO_START) { const struct brw_ubo_range *range = &prog_data->ubo_ranges[src.nr - UBO_START]; /* If this access is in our (reduced) range, use the push data. */ if (src.offset / 32 < range->length) return false; *out_surf_index = prog_data->binding_table.ubo_start + range->block; *out_pull_index = (32 * range->start + src.offset) / 4; return true; } const unsigned location = src.nr + src.offset / 4; if (location < uniforms && pull_constant_loc[location] != -1) { /* A regular uniform push constant */ *out_surf_index = stage_prog_data->binding_table.pull_constants_start; *out_pull_index = pull_constant_loc[location]; return true; } return false; } /** * Replace UNIFORM register file access with either UNIFORM_PULL_CONSTANT_LOAD * or VARYING_PULL_CONSTANT_LOAD instructions which load values into VGRFs. */ void fs_visitor::lower_constant_loads() { unsigned index, pull_index; foreach_block_and_inst_safe (block, fs_inst, inst, cfg) { /* Set up the annotation tracking for new generated instructions. */ const fs_builder ibld(this, block, inst); for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file != UNIFORM) continue; /* We'll handle this case later */ if (inst->opcode == SHADER_OPCODE_MOV_INDIRECT && i == 0) continue; if (!get_pull_locs(inst->src[i], &index, &pull_index)) continue; assert(inst->src[i].stride == 0); const unsigned block_sz = 64; /* Fetch one cacheline at a time. */ const fs_builder ubld = ibld.exec_all().group(block_sz / 4, 0); const fs_reg dst = ubld.vgrf(BRW_REGISTER_TYPE_UD); const unsigned base = pull_index * 4; ubld.emit(FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD, dst, brw_imm_ud(index), brw_imm_ud(base & ~(block_sz - 1))); /* Rewrite the instruction to use the temporary VGRF. */ inst->src[i].file = VGRF; inst->src[i].nr = dst.nr; inst->src[i].offset = (base & (block_sz - 1)) + inst->src[i].offset % 4; brw_mark_surface_used(prog_data, index); } if (inst->opcode == SHADER_OPCODE_MOV_INDIRECT && inst->src[0].file == UNIFORM) { if (!get_pull_locs(inst->src[0], &index, &pull_index)) continue; VARYING_PULL_CONSTANT_LOAD(ibld, inst->dst, brw_imm_ud(index), inst->src[1], pull_index * 4); inst->remove(block); brw_mark_surface_used(prog_data, index); } } invalidate_live_intervals(); } bool fs_visitor::opt_algebraic() { bool progress = false; foreach_block_and_inst(block, fs_inst, inst, cfg) { switch (inst->opcode) { case BRW_OPCODE_MOV: if (inst->src[0].file != IMM) break; if (inst->saturate) { if (inst->dst.type != inst->src[0].type) assert(!"unimplemented: saturate mixed types"); if (brw_saturate_immediate(inst->dst.type, &inst->src[0].as_brw_reg())) { inst->saturate = false; progress = true; } } break; case BRW_OPCODE_MUL: if (inst->src[1].file != IMM) continue; /* a * 1.0 = a */ if (inst->src[1].is_one()) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; progress = true; break; } /* a * -1.0 = -a */ if (inst->src[1].is_negative_one()) { inst->opcode = BRW_OPCODE_MOV; inst->src[0].negate = !inst->src[0].negate; inst->src[1] = reg_undef; progress = true; break; } /* a * 0.0 = 0.0 */ if (inst->src[1].is_zero()) { inst->opcode = BRW_OPCODE_MOV; inst->src[0] = inst->src[1]; inst->src[1] = reg_undef; progress = true; break; } if (inst->src[0].file == IMM) { assert(inst->src[0].type == BRW_REGISTER_TYPE_F); inst->opcode = BRW_OPCODE_MOV; inst->src[0].f *= inst->src[1].f; inst->src[1] = reg_undef; progress = true; break; } break; case BRW_OPCODE_ADD: if (inst->src[1].file != IMM) continue; /* a + 0.0 = a */ if (inst->src[1].is_zero()) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; progress = true; break; } if (inst->src[0].file == IMM) { assert(inst->src[0].type == BRW_REGISTER_TYPE_F); inst->opcode = BRW_OPCODE_MOV; inst->src[0].f += inst->src[1].f; inst->src[1] = reg_undef; progress = true; break; } break; case BRW_OPCODE_OR: if (inst->src[0].equals(inst->src[1])) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; progress = true; break; } break; case BRW_OPCODE_LRP: if (inst->src[1].equals(inst->src[2])) { inst->opcode = BRW_OPCODE_MOV; inst->src[0] = inst->src[1]; inst->src[1] = reg_undef; inst->src[2] = reg_undef; progress = true; break; } break; case BRW_OPCODE_CMP: if (inst->conditional_mod == BRW_CONDITIONAL_GE && inst->src[0].abs && inst->src[0].negate && inst->src[1].is_zero()) { inst->src[0].abs = false; inst->src[0].negate = false; inst->conditional_mod = BRW_CONDITIONAL_Z; progress = true; break; } break; case BRW_OPCODE_SEL: if (inst->src[0].equals(inst->src[1])) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; inst->predicate = BRW_PREDICATE_NONE; inst->predicate_inverse = false; progress = true; } else if (inst->saturate && inst->src[1].file == IMM) { switch (inst->conditional_mod) { case BRW_CONDITIONAL_LE: case BRW_CONDITIONAL_L: switch (inst->src[1].type) { case BRW_REGISTER_TYPE_F: if (inst->src[1].f >= 1.0f) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; inst->conditional_mod = BRW_CONDITIONAL_NONE; progress = true; } break; default: break; } break; case BRW_CONDITIONAL_GE: case BRW_CONDITIONAL_G: switch (inst->src[1].type) { case BRW_REGISTER_TYPE_F: if (inst->src[1].f <= 0.0f) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; inst->conditional_mod = BRW_CONDITIONAL_NONE; progress = true; } break; default: break; } default: break; } } break; case BRW_OPCODE_MAD: if (inst->src[1].is_zero() || inst->src[2].is_zero()) { inst->opcode = BRW_OPCODE_MOV; inst->src[1] = reg_undef; inst->src[2] = reg_undef; progress = true; } else if (inst->src[0].is_zero()) { inst->opcode = BRW_OPCODE_MUL; inst->src[0] = inst->src[2]; inst->src[2] = reg_undef; progress = true; } else if (inst->src[1].is_one()) { inst->opcode = BRW_OPCODE_ADD; inst->src[1] = inst->src[2]; inst->src[2] = reg_undef; progress = true; } else if (inst->src[2].is_one()) { inst->opcode = BRW_OPCODE_ADD; inst->src[2] = reg_undef; progress = true; } else if (inst->src[1].file == IMM && inst->src[2].file == IMM) { inst->opcode = BRW_OPCODE_ADD; inst->src[1].f *= inst->src[2].f; inst->src[2] = reg_undef; progress = true; } break; case SHADER_OPCODE_BROADCAST: if (is_uniform(inst->src[0])) { inst->opcode = BRW_OPCODE_MOV; inst->sources = 1; inst->force_writemask_all = true; progress = true; } else if (inst->src[1].file == IMM) { inst->opcode = BRW_OPCODE_MOV; inst->src[0] = component(inst->src[0], inst->src[1].ud); inst->sources = 1; inst->force_writemask_all = true; progress = true; } break; default: break; } /* Swap if src[0] is immediate. */ if (progress && inst->is_commutative()) { if (inst->src[0].file == IMM) { fs_reg tmp = inst->src[1]; inst->src[1] = inst->src[0]; inst->src[0] = tmp; } } } return progress; } /** * Optimize sample messages that have constant zero values for the trailing * texture coordinates. We can just reduce the message length for these * instructions instead of reserving a register for it. Trailing parameters * that aren't sent default to zero anyway. This will cause the dead code * eliminator to remove the MOV instruction that would otherwise be emitted to * set up the zero value. */ bool fs_visitor::opt_zero_samples() { /* Gen4 infers the texturing opcode based on the message length so we can't * change it. */ if (devinfo->gen < 5) return false; bool progress = false; foreach_block_and_inst(block, fs_inst, inst, cfg) { if (!inst->is_tex()) continue; fs_inst *load_payload = (fs_inst *) inst->prev; if (load_payload->is_head_sentinel() || load_payload->opcode != SHADER_OPCODE_LOAD_PAYLOAD) continue; /* We don't want to remove the message header or the first parameter. * Removing the first parameter is not allowed, see the Haswell PRM * volume 7, page 149: * * "Parameter 0 is required except for the sampleinfo message, which * has no parameter 0" */ while (inst->mlen > inst->header_size + inst->exec_size / 8 && load_payload->src[(inst->mlen - inst->header_size) / (inst->exec_size / 8) + inst->header_size - 1].is_zero()) { inst->mlen -= inst->exec_size / 8; progress = true; } } if (progress) invalidate_live_intervals(); return progress; } /** * Optimize sample messages which are followed by the final RT write. * * CHV, and GEN9+ can mark a texturing SEND instruction with EOT to have its * results sent directly to the framebuffer, bypassing the EU. Recognize the * final texturing results copied to the framebuffer write payload and modify * them to write to the framebuffer directly. */ bool fs_visitor::opt_sampler_eot() { brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; if (stage != MESA_SHADER_FRAGMENT) return false; if (devinfo->gen != 9 && !devinfo->is_cherryview) return false; /* FINISHME: It should be possible to implement this optimization when there * are multiple drawbuffers. */ if (key->nr_color_regions != 1) return false; /* Requires emitting a bunch of saturating MOV instructions during logical * send lowering to clamp the color payload, which the sampler unit isn't * going to do for us. */ if (key->clamp_fragment_color) return false; /* Look for a texturing instruction immediately before the final FB_WRITE. */ bblock_t *block = cfg->blocks[cfg->num_blocks - 1]; fs_inst *fb_write = (fs_inst *)block->end(); assert(fb_write->eot); assert(fb_write->opcode == FS_OPCODE_FB_WRITE_LOGICAL); /* There wasn't one; nothing to do. */ if (unlikely(fb_write->prev->is_head_sentinel())) return false; fs_inst *tex_inst = (fs_inst *) fb_write->prev; /* 3D Sampler » Messages » Message Format * * “Response Length of zero is allowed on all SIMD8* and SIMD16* sampler * messages except sample+killpix, resinfo, sampleinfo, LOD, and gather4*” */ if (tex_inst->opcode != SHADER_OPCODE_TEX_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXD_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXF_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXL_LOGICAL && tex_inst->opcode != FS_OPCODE_TXB_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXF_CMS_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXF_CMS_W_LOGICAL && tex_inst->opcode != SHADER_OPCODE_TXF_UMS_LOGICAL) return false; /* XXX - This shouldn't be necessary. */ if (tex_inst->prev->is_head_sentinel()) return false; /* Check that the FB write sources are fully initialized by the single * texturing instruction. */ for (unsigned i = 0; i < FB_WRITE_LOGICAL_NUM_SRCS; i++) { if (i == FB_WRITE_LOGICAL_SRC_COLOR0) { if (!fb_write->src[i].equals(tex_inst->dst) || fb_write->size_read(i) != tex_inst->size_written) return false; } else if (i != FB_WRITE_LOGICAL_SRC_COMPONENTS) { if (fb_write->src[i].file != BAD_FILE) return false; } } assert(!tex_inst->eot); /* We can't get here twice */ assert((tex_inst->offset & (0xff << 24)) == 0); const fs_builder ibld(this, block, tex_inst); tex_inst->offset |= fb_write->target << 24; tex_inst->eot = true; tex_inst->dst = ibld.null_reg_ud(); tex_inst->size_written = 0; fb_write->remove(cfg->blocks[cfg->num_blocks - 1]); /* Marking EOT is sufficient, lower_logical_sends() will notice the EOT * flag and submit a header together with the sampler message as required * by the hardware. */ invalidate_live_intervals(); return true; } bool fs_visitor::opt_register_renaming() { bool progress = false; int depth = 0; int remap[alloc.count]; memset(remap, -1, sizeof(int) * alloc.count); foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->opcode == BRW_OPCODE_IF || inst->opcode == BRW_OPCODE_DO) { depth++; } else if (inst->opcode == BRW_OPCODE_ENDIF || inst->opcode == BRW_OPCODE_WHILE) { depth--; } /* Rewrite instruction sources. */ for (int i = 0; i < inst->sources; i++) { if (inst->src[i].file == VGRF && remap[inst->src[i].nr] != -1 && remap[inst->src[i].nr] != inst->src[i].nr) { inst->src[i].nr = remap[inst->src[i].nr]; progress = true; } } const int dst = inst->dst.nr; if (depth == 0 && inst->dst.file == VGRF && alloc.sizes[inst->dst.nr] * REG_SIZE == inst->size_written && !inst->is_partial_write()) { if (remap[dst] == -1) { remap[dst] = dst; } else { remap[dst] = alloc.allocate(regs_written(inst)); inst->dst.nr = remap[dst]; progress = true; } } else if (inst->dst.file == VGRF && remap[dst] != -1 && remap[dst] != dst) { inst->dst.nr = remap[dst]; progress = true; } } if (progress) { invalidate_live_intervals(); for (unsigned i = 0; i < ARRAY_SIZE(delta_xy); i++) { if (delta_xy[i].file == VGRF && remap[delta_xy[i].nr] != -1) { delta_xy[i].nr = remap[delta_xy[i].nr]; } } } return progress; } /** * Remove redundant or useless discard jumps. * * For example, we can eliminate jumps in the following sequence: * * discard-jump (redundant with the next jump) * discard-jump (useless; jumps to the next instruction) * placeholder-halt */ bool fs_visitor::opt_redundant_discard_jumps() { bool progress = false; bblock_t *last_bblock = cfg->blocks[cfg->num_blocks - 1]; fs_inst *placeholder_halt = NULL; foreach_inst_in_block_reverse(fs_inst, inst, last_bblock) { if (inst->opcode == FS_OPCODE_PLACEHOLDER_HALT) { placeholder_halt = inst; break; } } if (!placeholder_halt) return false; /* Delete any HALTs immediately before the placeholder halt. */ for (fs_inst *prev = (fs_inst *) placeholder_halt->prev; !prev->is_head_sentinel() && prev->opcode == FS_OPCODE_DISCARD_JUMP; prev = (fs_inst *) placeholder_halt->prev) { prev->remove(last_bblock); progress = true; } if (progress) invalidate_live_intervals(); return progress; } /** * Compute a bitmask with GRF granularity with a bit set for each GRF starting * from \p r.offset which overlaps the region starting at \p s.offset and * spanning \p ds bytes. */ static inline unsigned mask_relative_to(const fs_reg &r, const fs_reg &s, unsigned ds) { const int rel_offset = reg_offset(s) - reg_offset(r); const int shift = rel_offset / REG_SIZE; const unsigned n = DIV_ROUND_UP(rel_offset % REG_SIZE + ds, REG_SIZE); assert(reg_space(r) == reg_space(s) && shift >= 0 && shift < int(8 * sizeof(unsigned))); return ((1 << n) - 1) << shift; } bool fs_visitor::compute_to_mrf() { bool progress = false; int next_ip = 0; /* No MRFs on Gen >= 7. */ if (devinfo->gen >= 7) return false; calculate_live_intervals(); foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { int ip = next_ip; next_ip++; if (inst->opcode != BRW_OPCODE_MOV || inst->is_partial_write() || inst->dst.file != MRF || inst->src[0].file != VGRF || inst->dst.type != inst->src[0].type || inst->src[0].abs || inst->src[0].negate || !inst->src[0].is_contiguous() || inst->src[0].offset % REG_SIZE != 0) continue; /* Can't compute-to-MRF this GRF if someone else was going to * read it later. */ if (this->virtual_grf_end[inst->src[0].nr] > ip) continue; /* Found a move of a GRF to a MRF. Let's see if we can go rewrite the * things that computed the value of all GRFs of the source region. The * regs_left bitset keeps track of the registers we haven't yet found a * generating instruction for. */ unsigned regs_left = (1 << regs_read(inst, 0)) - 1; foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { if (regions_overlap(scan_inst->dst, scan_inst->size_written, inst->src[0], inst->size_read(0))) { /* Found the last thing to write our reg we want to turn * into a compute-to-MRF. */ /* If this one instruction didn't populate all the * channels, bail. We might be able to rewrite everything * that writes that reg, but it would require smarter * tracking. */ if (scan_inst->is_partial_write()) break; /* Handling things not fully contained in the source of the copy * would need us to understand coalescing out more than one MOV at * a time. */ if (!region_contained_in(scan_inst->dst, scan_inst->size_written, inst->src[0], inst->size_read(0))) break; /* SEND instructions can't have MRF as a destination. */ if (scan_inst->mlen) break; if (devinfo->gen == 6) { /* gen6 math instructions must have the destination be * GRF, so no compute-to-MRF for them. */ if (scan_inst->is_math()) { break; } } /* Clear the bits for any registers this instruction overwrites. */ regs_left &= ~mask_relative_to( inst->src[0], scan_inst->dst, scan_inst->size_written); if (!regs_left) break; } /* We don't handle control flow here. Most computation of * values that end up in MRFs are shortly before the MRF * write anyway. */ if (block->start() == scan_inst) break; /* You can't read from an MRF, so if someone else reads our * MRF's source GRF that we wanted to rewrite, that stops us. */ bool interfered = false; for (int i = 0; i < scan_inst->sources; i++) { if (regions_overlap(scan_inst->src[i], scan_inst->size_read(i), inst->src[0], inst->size_read(0))) { interfered = true; } } if (interfered) break; if (regions_overlap(scan_inst->dst, scan_inst->size_written, inst->dst, inst->size_written)) { /* If somebody else writes our MRF here, we can't * compute-to-MRF before that. */ break; } if (scan_inst->mlen > 0 && scan_inst->base_mrf != -1 && regions_overlap(fs_reg(MRF, scan_inst->base_mrf), scan_inst->mlen * REG_SIZE, inst->dst, inst->size_written)) { /* Found a SEND instruction, which means that there are * live values in MRFs from base_mrf to base_mrf + * scan_inst->mlen - 1. Don't go pushing our MRF write up * above it. */ break; } } if (regs_left) continue; /* Found all generating instructions of our MRF's source value, so it * should be safe to rewrite them to point to the MRF directly. */ regs_left = (1 << regs_read(inst, 0)) - 1; foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { if (regions_overlap(scan_inst->dst, scan_inst->size_written, inst->src[0], inst->size_read(0))) { /* Clear the bits for any registers this instruction overwrites. */ regs_left &= ~mask_relative_to( inst->src[0], scan_inst->dst, scan_inst->size_written); const unsigned rel_offset = reg_offset(scan_inst->dst) - reg_offset(inst->src[0]); if (inst->dst.nr & BRW_MRF_COMPR4) { /* Apply the same address transformation done by the hardware * for COMPR4 MRF writes. */ assert(rel_offset < 2 * REG_SIZE); scan_inst->dst.nr = inst->dst.nr + rel_offset / REG_SIZE * 4; /* Clear the COMPR4 bit if the generating instruction is not * compressed. */ if (scan_inst->size_written < 2 * REG_SIZE) scan_inst->dst.nr &= ~BRW_MRF_COMPR4; } else { /* Calculate the MRF number the result of this instruction is * ultimately written to. */ scan_inst->dst.nr = inst->dst.nr + rel_offset / REG_SIZE; } scan_inst->dst.file = MRF; scan_inst->dst.offset = inst->dst.offset + rel_offset % REG_SIZE; scan_inst->saturate |= inst->saturate; if (!regs_left) break; } } assert(!regs_left); inst->remove(block); progress = true; } if (progress) invalidate_live_intervals(); return progress; } /** * Eliminate FIND_LIVE_CHANNEL instructions occurring outside any control * flow. We could probably do better here with some form of divergence * analysis. */ bool fs_visitor::eliminate_find_live_channel() { bool progress = false; unsigned depth = 0; if (!brw_stage_has_packed_dispatch(devinfo, stage, stage_prog_data)) { /* The optimization below assumes that channel zero is live on thread * dispatch, which may not be the case if the fixed function dispatches * threads sparsely. */ return false; } foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { switch (inst->opcode) { case BRW_OPCODE_IF: case BRW_OPCODE_DO: depth++; break; case BRW_OPCODE_ENDIF: case BRW_OPCODE_WHILE: depth--; break; case FS_OPCODE_DISCARD_JUMP: /* This can potentially make control flow non-uniform until the end * of the program. */ return progress; case SHADER_OPCODE_FIND_LIVE_CHANNEL: if (depth == 0) { inst->opcode = BRW_OPCODE_MOV; inst->src[0] = brw_imm_ud(0u); inst->sources = 1; inst->force_writemask_all = true; progress = true; } break; default: break; } } return progress; } /** * Once we've generated code, try to convert normal FS_OPCODE_FB_WRITE * instructions to FS_OPCODE_REP_FB_WRITE. */ void fs_visitor::emit_repclear_shader() { brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; int base_mrf = 0; int color_mrf = base_mrf + 2; fs_inst *mov; if (uniforms > 0) { mov = bld.exec_all().group(4, 0) .MOV(brw_message_reg(color_mrf), fs_reg(UNIFORM, 0, BRW_REGISTER_TYPE_F)); } else { struct brw_reg reg = brw_reg(BRW_GENERAL_REGISTER_FILE, 2, 3, 0, 0, BRW_REGISTER_TYPE_F, BRW_VERTICAL_STRIDE_8, BRW_WIDTH_2, BRW_HORIZONTAL_STRIDE_4, BRW_SWIZZLE_XYZW, WRITEMASK_XYZW); mov = bld.exec_all().group(4, 0) .MOV(vec4(brw_message_reg(color_mrf)), fs_reg(reg)); } fs_inst *write; if (key->nr_color_regions == 1) { write = bld.emit(FS_OPCODE_REP_FB_WRITE); write->saturate = key->clamp_fragment_color; write->base_mrf = color_mrf; write->target = 0; write->header_size = 0; write->mlen = 1; } else { assume(key->nr_color_regions > 0); for (int i = 0; i < key->nr_color_regions; ++i) { write = bld.emit(FS_OPCODE_REP_FB_WRITE); write->saturate = key->clamp_fragment_color; write->base_mrf = base_mrf; write->target = i; write->header_size = 2; write->mlen = 3; } } write->eot = true; calculate_cfg(); assign_constant_locations(); assign_curb_setup(); /* Now that we have the uniform assigned, go ahead and force it to a vec4. */ if (uniforms > 0) { assert(mov->src[0].file == FIXED_GRF); mov->src[0] = brw_vec4_grf(mov->src[0].nr, 0); } } /** * Walks through basic blocks, looking for repeated MRF writes and * removing the later ones. */ bool fs_visitor::remove_duplicate_mrf_writes() { fs_inst *last_mrf_move[BRW_MAX_MRF(devinfo->gen)]; bool progress = false; /* Need to update the MRF tracking for compressed instructions. */ if (dispatch_width >= 16) return false; memset(last_mrf_move, 0, sizeof(last_mrf_move)); foreach_block_and_inst_safe (block, fs_inst, inst, cfg) { if (inst->is_control_flow()) { memset(last_mrf_move, 0, sizeof(last_mrf_move)); } if (inst->opcode == BRW_OPCODE_MOV && inst->dst.file == MRF) { fs_inst *prev_inst = last_mrf_move[inst->dst.nr]; if (prev_inst && inst->equals(prev_inst)) { inst->remove(block); progress = true; continue; } } /* Clear out the last-write records for MRFs that were overwritten. */ if (inst->dst.file == MRF) { last_mrf_move[inst->dst.nr] = NULL; } if (inst->mlen > 0 && inst->base_mrf != -1) { /* Found a SEND instruction, which will include two or fewer * implied MRF writes. We could do better here. */ for (int i = 0; i < implied_mrf_writes(inst); i++) { last_mrf_move[inst->base_mrf + i] = NULL; } } /* Clear out any MRF move records whose sources got overwritten. */ for (unsigned i = 0; i < ARRAY_SIZE(last_mrf_move); i++) { if (last_mrf_move[i] && regions_overlap(inst->dst, inst->size_written, last_mrf_move[i]->src[0], last_mrf_move[i]->size_read(0))) { last_mrf_move[i] = NULL; } } if (inst->opcode == BRW_OPCODE_MOV && inst->dst.file == MRF && inst->src[0].file != ARF && !inst->is_partial_write()) { last_mrf_move[inst->dst.nr] = inst; } } if (progress) invalidate_live_intervals(); return progress; } static void clear_deps_for_inst_src(fs_inst *inst, bool *deps, int first_grf, int grf_len) { /* Clear the flag for registers that actually got read (as expected). */ for (int i = 0; i < inst->sources; i++) { int grf; if (inst->src[i].file == VGRF || inst->src[i].file == FIXED_GRF) { grf = inst->src[i].nr; } else { continue; } if (grf >= first_grf && grf < first_grf + grf_len) { deps[grf - first_grf] = false; if (inst->exec_size == 16) deps[grf - first_grf + 1] = false; } } } /** * Implements this workaround for the original 965: * * "[DevBW, DevCL] Implementation Restrictions: As the hardware does not * check for post destination dependencies on this instruction, software * must ensure that there is no destination hazard for the case of ‘write * followed by a posted write’ shown in the following example. * * 1. mov r3 0 * 2. send r3.xy * 3. mov r2 r3 * * Due to no post-destination dependency check on the ‘send’, the above * code sequence could have two instructions (1 and 2) in flight at the * same time that both consider ‘r3’ as the target of their final writes. */ void fs_visitor::insert_gen4_pre_send_dependency_workarounds(bblock_t *block, fs_inst *inst) { int write_len = regs_written(inst); int first_write_grf = inst->dst.nr; bool needs_dep[BRW_MAX_MRF(devinfo->gen)]; assert(write_len < (int)sizeof(needs_dep) - 1); memset(needs_dep, false, sizeof(needs_dep)); memset(needs_dep, true, write_len); clear_deps_for_inst_src(inst, needs_dep, first_write_grf, write_len); /* Walk backwards looking for writes to registers we're writing which * aren't read since being written. If we hit the start of the program, * we assume that there are no outstanding dependencies on entry to the * program. */ foreach_inst_in_block_reverse_starting_from(fs_inst, scan_inst, inst) { /* If we hit control flow, assume that there *are* outstanding * dependencies, and force their cleanup before our instruction. */ if (block->start() == scan_inst && block->num != 0) { for (int i = 0; i < write_len; i++) { if (needs_dep[i]) DEP_RESOLVE_MOV(fs_builder(this, block, inst), first_write_grf + i); } return; } /* We insert our reads as late as possible on the assumption that any * instruction but a MOV that might have left us an outstanding * dependency has more latency than a MOV. */ if (scan_inst->dst.file == VGRF) { for (unsigned i = 0; i < regs_written(scan_inst); i++) { int reg = scan_inst->dst.nr + i; if (reg >= first_write_grf && reg < first_write_grf + write_len && needs_dep[reg - first_write_grf]) { DEP_RESOLVE_MOV(fs_builder(this, block, inst), reg); needs_dep[reg - first_write_grf] = false; if (scan_inst->exec_size == 16) needs_dep[reg - first_write_grf + 1] = false; } } } /* Clear the flag for registers that actually got read (as expected). */ clear_deps_for_inst_src(scan_inst, needs_dep, first_write_grf, write_len); /* Continue the loop only if we haven't resolved all the dependencies */ int i; for (i = 0; i < write_len; i++) { if (needs_dep[i]) break; } if (i == write_len) return; } } /** * Implements this workaround for the original 965: * * "[DevBW, DevCL] Errata: A destination register from a send can not be * used as a destination register until after it has been sourced by an * instruction with a different destination register. */ void fs_visitor::insert_gen4_post_send_dependency_workarounds(bblock_t *block, fs_inst *inst) { int write_len = regs_written(inst); int first_write_grf = inst->dst.nr; bool needs_dep[BRW_MAX_MRF(devinfo->gen)]; assert(write_len < (int)sizeof(needs_dep) - 1); memset(needs_dep, false, sizeof(needs_dep)); memset(needs_dep, true, write_len); /* Walk forwards looking for writes to registers we're writing which aren't * read before being written. */ foreach_inst_in_block_starting_from(fs_inst, scan_inst, inst) { /* If we hit control flow, force resolve all remaining dependencies. */ if (block->end() == scan_inst && block->num != cfg->num_blocks - 1) { for (int i = 0; i < write_len; i++) { if (needs_dep[i]) DEP_RESOLVE_MOV(fs_builder(this, block, scan_inst), first_write_grf + i); } return; } /* Clear the flag for registers that actually got read (as expected). */ clear_deps_for_inst_src(scan_inst, needs_dep, first_write_grf, write_len); /* We insert our reads as late as possible since they're reading the * result of a SEND, which has massive latency. */ if (scan_inst->dst.file == VGRF && scan_inst->dst.nr >= first_write_grf && scan_inst->dst.nr < first_write_grf + write_len && needs_dep[scan_inst->dst.nr - first_write_grf]) { DEP_RESOLVE_MOV(fs_builder(this, block, scan_inst), scan_inst->dst.nr); needs_dep[scan_inst->dst.nr - first_write_grf] = false; } /* Continue the loop only if we haven't resolved all the dependencies */ int i; for (i = 0; i < write_len; i++) { if (needs_dep[i]) break; } if (i == write_len) return; } } void fs_visitor::insert_gen4_send_dependency_workarounds() { if (devinfo->gen != 4 || devinfo->is_g4x) return; bool progress = false; foreach_block_and_inst(block, fs_inst, inst, cfg) { if (inst->mlen != 0 && inst->dst.file == VGRF) { insert_gen4_pre_send_dependency_workarounds(block, inst); insert_gen4_post_send_dependency_workarounds(block, inst); progress = true; } } if (progress) invalidate_live_intervals(); } /** * Turns the generic expression-style uniform pull constant load instruction * into a hardware-specific series of instructions for loading a pull * constant. * * The expression style allows the CSE pass before this to optimize out * repeated loads from the same offset, and gives the pre-register-allocation * scheduling full flexibility, while the conversion to native instructions * allows the post-register-allocation scheduler the best information * possible. * * Note that execution masking for setting up pull constant loads is special: * the channels that need to be written are unrelated to the current execution * mask, since a later instruction will use one of the result channels as a * source operand for all 8 or 16 of its channels. */ void fs_visitor::lower_uniform_pull_constant_loads() { foreach_block_and_inst (block, fs_inst, inst, cfg) { if (inst->opcode != FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD) continue; if (devinfo->gen >= 7) { const fs_builder ubld = fs_builder(this, block, inst).exec_all(); const fs_reg payload = ubld.group(8, 0).vgrf(BRW_REGISTER_TYPE_UD); ubld.group(8, 0).MOV(payload, retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD)); ubld.group(1, 0).MOV(component(payload, 2), brw_imm_ud(inst->src[1].ud / 16)); inst->opcode = FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7; inst->src[1] = payload; inst->header_size = 1; inst->mlen = 1; invalidate_live_intervals(); } else { /* Before register allocation, we didn't tell the scheduler about the * MRF we use. We know it's safe to use this MRF because nothing * else does except for register spill/unspill, which generates and * uses its MRF within a single IR instruction. */ inst->base_mrf = FIRST_PULL_LOAD_MRF(devinfo->gen) + 1; inst->mlen = 1; } } } bool fs_visitor::lower_load_payload() { bool progress = false; foreach_block_and_inst_safe (block, fs_inst, inst, cfg) { if (inst->opcode != SHADER_OPCODE_LOAD_PAYLOAD) continue; assert(inst->dst.file == MRF || inst->dst.file == VGRF); assert(inst->saturate == false); fs_reg dst = inst->dst; /* Get rid of COMPR4. We'll add it back in if we need it */ if (dst.file == MRF) dst.nr = dst.nr & ~BRW_MRF_COMPR4; const fs_builder ibld(this, block, inst); const fs_builder hbld = ibld.exec_all().group(8, 0); for (uint8_t i = 0; i < inst->header_size; i++) { if (inst->src[i].file != BAD_FILE) { fs_reg mov_dst = retype(dst, BRW_REGISTER_TYPE_UD); fs_reg mov_src = retype(inst->src[i], BRW_REGISTER_TYPE_UD); hbld.MOV(mov_dst, mov_src); } dst = offset(dst, hbld, 1); } if (inst->dst.file == MRF && (inst->dst.nr & BRW_MRF_COMPR4) && inst->exec_size > 8) { /* In this case, the payload portion of the LOAD_PAYLOAD isn't * a straightforward copy. Instead, the result of the * LOAD_PAYLOAD is treated as interleaved and the first four * non-header sources are unpacked as: * * m + 0: r0 * m + 1: g0 * m + 2: b0 * m + 3: a0 * m + 4: r1 * m + 5: g1 * m + 6: b1 * m + 7: a1 * * This is used for gen <= 5 fb writes. */ assert(inst->exec_size == 16); assert(inst->header_size + 4 <= inst->sources); for (uint8_t i = inst->header_size; i < inst->header_size + 4; i++) { if (inst->src[i].file != BAD_FILE) { if (devinfo->has_compr4) { fs_reg compr4_dst = retype(dst, inst->src[i].type); compr4_dst.nr |= BRW_MRF_COMPR4; ibld.MOV(compr4_dst, inst->src[i]); } else { /* Platform doesn't have COMPR4. We have to fake it */ fs_reg mov_dst = retype(dst, inst->src[i].type); ibld.half(0).MOV(mov_dst, half(inst->src[i], 0)); mov_dst.nr += 4; ibld.half(1).MOV(mov_dst, half(inst->src[i], 1)); } } dst.nr++; } /* The loop above only ever incremented us through the first set * of 4 registers. However, thanks to the magic of COMPR4, we * actually wrote to the first 8 registers, so we need to take * that into account now. */ dst.nr += 4; /* The COMPR4 code took care of the first 4 sources. We'll let * the regular path handle any remaining sources. Yes, we are * modifying the instruction but we're about to delete it so * this really doesn't hurt anything. */ inst->header_size += 4; } for (uint8_t i = inst->header_size; i < inst->sources; i++) { if (inst->src[i].file != BAD_FILE) ibld.MOV(retype(dst, inst->src[i].type), inst->src[i]); dst = offset(dst, ibld, 1); } inst->remove(block); progress = true; } if (progress) invalidate_live_intervals(); return progress; } bool fs_visitor::lower_integer_multiplication() { bool progress = false; foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { const fs_builder ibld(this, block, inst); if (inst->opcode == BRW_OPCODE_MUL) { if (inst->dst.is_accumulator() || (inst->dst.type != BRW_REGISTER_TYPE_D && inst->dst.type != BRW_REGISTER_TYPE_UD)) continue; /* Gen8's MUL instruction can do a 32-bit x 32-bit -> 32-bit * operation directly, but CHV/BXT cannot. */ if (devinfo->gen >= 8 && !devinfo->is_cherryview && !gen_device_info_is_9lp(devinfo)) continue; if (inst->src[1].file == IMM && inst->src[1].ud < (1 << 16)) { /* The MUL instruction isn't commutative. On Gen <= 6, only the low * 16-bits of src0 are read, and on Gen >= 7 only the low 16-bits of * src1 are used. * * If multiplying by an immediate value that fits in 16-bits, do a * single MUL instruction with that value in the proper location. */ if (devinfo->gen < 7) { fs_reg imm(VGRF, alloc.allocate(dispatch_width / 8), inst->dst.type); ibld.MOV(imm, inst->src[1]); ibld.MUL(inst->dst, imm, inst->src[0]); } else { const bool ud = (inst->src[1].type == BRW_REGISTER_TYPE_UD); ibld.MUL(inst->dst, inst->src[0], ud ? brw_imm_uw(inst->src[1].ud) : brw_imm_w(inst->src[1].d)); } } else { /* Gen < 8 (and some Gen8+ low-power parts like Cherryview) cannot * do 32-bit integer multiplication in one instruction, but instead * must do a sequence (which actually calculates a 64-bit result): * * mul(8) acc0<1>D g3<8,8,1>D g4<8,8,1>D * mach(8) null g3<8,8,1>D g4<8,8,1>D * mov(8) g2<1>D acc0<8,8,1>D * * But on Gen > 6, the ability to use second accumulator register * (acc1) for non-float data types was removed, preventing a simple * implementation in SIMD16. A 16-channel result can be calculated by * executing the three instructions twice in SIMD8, once with quarter * control of 1Q for the first eight channels and again with 2Q for * the second eight channels. * * Which accumulator register is implicitly accessed (by AccWrEnable * for instance) is determined by the quarter control. Unfortunately * Ivybridge (and presumably Baytrail) has a hardware bug in which an * implicit accumulator access by an instruction with 2Q will access * acc1 regardless of whether the data type is usable in acc1. * * Specifically, the 2Q mach(8) writes acc1 which does not exist for * integer data types. * * Since we only want the low 32-bits of the result, we can do two * 32-bit x 16-bit multiplies (like the mul and mach are doing), and * adjust the high result and add them (like the mach is doing): * * mul(8) g7<1>D g3<8,8,1>D g4.0<8,8,1>UW * mul(8) g8<1>D g3<8,8,1>D g4.1<8,8,1>UW * shl(8) g9<1>D g8<8,8,1>D 16D * add(8) g2<1>D g7<8,8,1>D g8<8,8,1>D * * We avoid the shl instruction by realizing that we only want to add * the low 16-bits of the "high" result to the high 16-bits of the * "low" result and using proper regioning on the add: * * mul(8) g7<1>D g3<8,8,1>D g4.0<16,8,2>UW * mul(8) g8<1>D g3<8,8,1>D g4.1<16,8,2>UW * add(8) g7.1<2>UW g7.1<16,8,2>UW g8<16,8,2>UW * * Since it does not use the (single) accumulator register, we can * schedule multi-component multiplications much better. */ fs_reg orig_dst = inst->dst; if (orig_dst.is_null() || orig_dst.file == MRF) { inst->dst = fs_reg(VGRF, alloc.allocate(dispatch_width / 8), inst->dst.type); } fs_reg low = inst->dst; fs_reg high(VGRF, alloc.allocate(dispatch_width / 8), inst->dst.type); if (devinfo->gen >= 7) { if (inst->src[1].file == IMM) { ibld.MUL(low, inst->src[0], brw_imm_uw(inst->src[1].ud & 0xffff)); ibld.MUL(high, inst->src[0], brw_imm_uw(inst->src[1].ud >> 16)); } else { ibld.MUL(low, inst->src[0], subscript(inst->src[1], BRW_REGISTER_TYPE_UW, 0)); ibld.MUL(high, inst->src[0], subscript(inst->src[1], BRW_REGISTER_TYPE_UW, 1)); } } else { ibld.MUL(low, subscript(inst->src[0], BRW_REGISTER_TYPE_UW, 0), inst->src[1]); ibld.MUL(high, subscript(inst->src[0], BRW_REGISTER_TYPE_UW, 1), inst->src[1]); } ibld.ADD(subscript(inst->dst, BRW_REGISTER_TYPE_UW, 1), subscript(low, BRW_REGISTER_TYPE_UW, 1), subscript(high, BRW_REGISTER_TYPE_UW, 0)); if (inst->conditional_mod || orig_dst.file == MRF) { set_condmod(inst->conditional_mod, ibld.MOV(orig_dst, inst->dst)); } } } else if (inst->opcode == SHADER_OPCODE_MULH) { /* Should have been lowered to 8-wide. */ assert(inst->exec_size <= get_lowered_simd_width(devinfo, inst)); const fs_reg acc = retype(brw_acc_reg(inst->exec_size), inst->dst.type); fs_inst *mul = ibld.MUL(acc, inst->src[0], inst->src[1]); fs_inst *mach = ibld.MACH(inst->dst, inst->src[0], inst->src[1]); if (devinfo->gen >= 8) { /* Until Gen8, integer multiplies read 32-bits from one source, * and 16-bits from the other, and relying on the MACH instruction * to generate the high bits of the result. * * On Gen8, the multiply instruction does a full 32x32-bit * multiply, but in order to do a 64-bit multiply we can simulate * the previous behavior and then use a MACH instruction. * * FINISHME: Don't use source modifiers on src1. */ assert(mul->src[1].type == BRW_REGISTER_TYPE_D || mul->src[1].type == BRW_REGISTER_TYPE_UD); mul->src[1].type = BRW_REGISTER_TYPE_UW; mul->src[1].stride *= 2; } else if (devinfo->gen == 7 && !devinfo->is_haswell && inst->group > 0) { /* Among other things the quarter control bits influence which * accumulator register is used by the hardware for instructions * that access the accumulator implicitly (e.g. MACH). A * second-half instruction would normally map to acc1, which * doesn't exist on Gen7 and up (the hardware does emulate it for * floating-point instructions *only* by taking advantage of the * extra precision of acc0 not normally used for floating point * arithmetic). * * HSW and up are careful enough not to try to access an * accumulator register that doesn't exist, but on earlier Gen7 * hardware we need to make sure that the quarter control bits are * zero to avoid non-deterministic behaviour and emit an extra MOV * to get the result masked correctly according to the current * channel enables. */ mach->group = 0; mach->force_writemask_all = true; mach->dst = ibld.vgrf(inst->dst.type); ibld.MOV(inst->dst, mach->dst); } } else { continue; } inst->remove(block); progress = true; } if (progress) invalidate_live_intervals(); return progress; } bool fs_visitor::lower_minmax() { assert(devinfo->gen < 6); bool progress = false; foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { const fs_builder ibld(this, block, inst); if (inst->opcode == BRW_OPCODE_SEL && inst->predicate == BRW_PREDICATE_NONE) { /* FIXME: Using CMP doesn't preserve the NaN propagation semantics of * the original SEL.L/GE instruction */ ibld.CMP(ibld.null_reg_d(), inst->src[0], inst->src[1], inst->conditional_mod); inst->predicate = BRW_PREDICATE_NORMAL; inst->conditional_mod = BRW_CONDITIONAL_NONE; progress = true; } } if (progress) invalidate_live_intervals(); return progress; } static void setup_color_payload(const fs_builder &bld, const brw_wm_prog_key *key, fs_reg *dst, fs_reg color, unsigned components) { if (key->clamp_fragment_color) { fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_F, 4); assert(color.type == BRW_REGISTER_TYPE_F); for (unsigned i = 0; i < components; i++) set_saturate(true, bld.MOV(offset(tmp, bld, i), offset(color, bld, i))); color = tmp; } for (unsigned i = 0; i < components; i++) dst[i] = offset(color, bld, i); } static void lower_fb_write_logical_send(const fs_builder &bld, fs_inst *inst, const struct brw_wm_prog_data *prog_data, const brw_wm_prog_key *key, const fs_visitor::thread_payload &payload) { assert(inst->src[FB_WRITE_LOGICAL_SRC_COMPONENTS].file == IMM); const gen_device_info *devinfo = bld.shader->devinfo; const fs_reg &color0 = inst->src[FB_WRITE_LOGICAL_SRC_COLOR0]; const fs_reg &color1 = inst->src[FB_WRITE_LOGICAL_SRC_COLOR1]; const fs_reg &src0_alpha = inst->src[FB_WRITE_LOGICAL_SRC_SRC0_ALPHA]; const fs_reg &src_depth = inst->src[FB_WRITE_LOGICAL_SRC_SRC_DEPTH]; const fs_reg &dst_depth = inst->src[FB_WRITE_LOGICAL_SRC_DST_DEPTH]; const fs_reg &src_stencil = inst->src[FB_WRITE_LOGICAL_SRC_SRC_STENCIL]; fs_reg sample_mask = inst->src[FB_WRITE_LOGICAL_SRC_OMASK]; const unsigned components = inst->src[FB_WRITE_LOGICAL_SRC_COMPONENTS].ud; /* We can potentially have a message length of up to 15, so we have to set * base_mrf to either 0 or 1 in order to fit in m0..m15. */ fs_reg sources[15]; int header_size = 2, payload_header_size; unsigned length = 0; /* From the Sandy Bridge PRM, volume 4, page 198: * * "Dispatched Pixel Enables. One bit per pixel indicating * which pixels were originally enabled when the thread was * dispatched. This field is only required for the end-of- * thread message and on all dual-source messages." */ if (devinfo->gen >= 6 && (devinfo->is_haswell || devinfo->gen >= 8 || !prog_data->uses_kill) && color1.file == BAD_FILE && key->nr_color_regions == 1) { header_size = 0; } if (header_size != 0) { assert(header_size == 2); /* Allocate 2 registers for a header */ length += 2; } if (payload.aa_dest_stencil_reg) { sources[length] = fs_reg(VGRF, bld.shader->alloc.allocate(1)); bld.group(8, 0).exec_all().annotate("FB write stencil/AA alpha") .MOV(sources[length], fs_reg(brw_vec8_grf(payload.aa_dest_stencil_reg, 0))); length++; } if (sample_mask.file != BAD_FILE) { sources[length] = fs_reg(VGRF, bld.shader->alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* Hand over gl_SampleMask. Only the lower 16 bits of each channel are * relevant. Since it's unsigned single words one vgrf is always * 16-wide, but only the lower or higher 8 channels will be used by the * hardware when doing a SIMD8 write depending on whether we have * selected the subspans for the first or second half respectively. */ assert(sample_mask.file != BAD_FILE && type_sz(sample_mask.type) == 4); sample_mask.type = BRW_REGISTER_TYPE_UW; sample_mask.stride *= 2; bld.exec_all().annotate("FB write oMask") .MOV(horiz_offset(retype(sources[length], BRW_REGISTER_TYPE_UW), inst->group), sample_mask); length++; } payload_header_size = length; if (src0_alpha.file != BAD_FILE) { /* FIXME: This is being passed at the wrong location in the payload and * doesn't work when gl_SampleMask and MRTs are used simultaneously. * It's supposed to be immediately before oMask but there seems to be no * reasonable way to pass them in the correct order because LOAD_PAYLOAD * requires header sources to form a contiguous segment at the beginning * of the message and src0_alpha has per-channel semantics. */ setup_color_payload(bld, key, &sources[length], src0_alpha, 1); length++; } else if (key->replicate_alpha && inst->target != 0) { /* Handle the case when fragment shader doesn't write to draw buffer * zero. No need to call setup_color_payload() for src0_alpha because * alpha value will be undefined. */ length++; } setup_color_payload(bld, key, &sources[length], color0, components); length += 4; if (color1.file != BAD_FILE) { setup_color_payload(bld, key, &sources[length], color1, components); length += 4; } if (src_depth.file != BAD_FILE) { sources[length] = src_depth; length++; } if (dst_depth.file != BAD_FILE) { sources[length] = dst_depth; length++; } if (src_stencil.file != BAD_FILE) { assert(devinfo->gen >= 9); assert(bld.dispatch_width() != 16); /* XXX: src_stencil is only available on gen9+. dst_depth is never * available on gen9+. As such it's impossible to have both enabled at the * same time and therefore length cannot overrun the array. */ assert(length < 15); sources[length] = bld.vgrf(BRW_REGISTER_TYPE_UD); bld.exec_all().annotate("FB write OS") .MOV(retype(sources[length], BRW_REGISTER_TYPE_UB), subscript(src_stencil, BRW_REGISTER_TYPE_UB, 0)); length++; } fs_inst *load; if (devinfo->gen >= 7) { /* Send from the GRF */ fs_reg payload = fs_reg(VGRF, -1, BRW_REGISTER_TYPE_F); load = bld.LOAD_PAYLOAD(payload, sources, length, payload_header_size); payload.nr = bld.shader->alloc.allocate(regs_written(load)); load->dst = payload; inst->src[0] = payload; inst->resize_sources(1); } else { /* Send from the MRF */ load = bld.LOAD_PAYLOAD(fs_reg(MRF, 1, BRW_REGISTER_TYPE_F), sources, length, payload_header_size); /* On pre-SNB, we have to interlace the color values. LOAD_PAYLOAD * will do this for us if we just give it a COMPR4 destination. */ if (devinfo->gen < 6 && bld.dispatch_width() == 16) load->dst.nr |= BRW_MRF_COMPR4; inst->resize_sources(0); inst->base_mrf = 1; } inst->opcode = FS_OPCODE_FB_WRITE; inst->mlen = regs_written(load); inst->header_size = header_size; } static void lower_fb_read_logical_send(const fs_builder &bld, fs_inst *inst) { const fs_builder &ubld = bld.exec_all(); const unsigned length = 2; const fs_reg header = ubld.group(8, 0).vgrf(BRW_REGISTER_TYPE_UD, length); ubld.group(16, 0) .MOV(header, retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD)); inst->resize_sources(1); inst->src[0] = header; inst->opcode = FS_OPCODE_FB_READ; inst->mlen = length; inst->header_size = length; } static void lower_sampler_logical_send_gen4(const fs_builder &bld, fs_inst *inst, opcode op, const fs_reg &coordinate, const fs_reg &shadow_c, const fs_reg &lod, const fs_reg &lod2, const fs_reg &surface, const fs_reg &sampler, unsigned coord_components, unsigned grad_components) { const bool has_lod = (op == SHADER_OPCODE_TXL || op == FS_OPCODE_TXB || op == SHADER_OPCODE_TXF || op == SHADER_OPCODE_TXS); fs_reg msg_begin(MRF, 1, BRW_REGISTER_TYPE_F); fs_reg msg_end = msg_begin; /* g0 header. */ msg_end = offset(msg_end, bld.group(8, 0), 1); for (unsigned i = 0; i < coord_components; i++) bld.MOV(retype(offset(msg_end, bld, i), coordinate.type), offset(coordinate, bld, i)); msg_end = offset(msg_end, bld, coord_components); /* Messages other than SAMPLE and RESINFO in SIMD16 and TXD in SIMD8 * require all three components to be present and zero if they are unused. */ if (coord_components > 0 && (has_lod || shadow_c.file != BAD_FILE || (op == SHADER_OPCODE_TEX && bld.dispatch_width() == 8))) { for (unsigned i = coord_components; i < 3; i++) bld.MOV(offset(msg_end, bld, i), brw_imm_f(0.0f)); msg_end = offset(msg_end, bld, 3 - coord_components); } if (op == SHADER_OPCODE_TXD) { /* TXD unsupported in SIMD16 mode. */ assert(bld.dispatch_width() == 8); /* the slots for u and v are always present, but r is optional */ if (coord_components < 2) msg_end = offset(msg_end, bld, 2 - coord_components); /* P = u, v, r * dPdx = dudx, dvdx, drdx * dPdy = dudy, dvdy, drdy * * 1-arg: Does not exist. * * 2-arg: dudx dvdx dudy dvdy * dPdx.x dPdx.y dPdy.x dPdy.y * m4 m5 m6 m7 * * 3-arg: dudx dvdx drdx dudy dvdy drdy * dPdx.x dPdx.y dPdx.z dPdy.x dPdy.y dPdy.z * m5 m6 m7 m8 m9 m10 */ for (unsigned i = 0; i < grad_components; i++) bld.MOV(offset(msg_end, bld, i), offset(lod, bld, i)); msg_end = offset(msg_end, bld, MAX2(grad_components, 2)); for (unsigned i = 0; i < grad_components; i++) bld.MOV(offset(msg_end, bld, i), offset(lod2, bld, i)); msg_end = offset(msg_end, bld, MAX2(grad_components, 2)); } if (has_lod) { /* Bias/LOD with shadow comparator is unsupported in SIMD16 -- *Without* * shadow comparator (including RESINFO) it's unsupported in SIMD8 mode. */ assert(shadow_c.file != BAD_FILE ? bld.dispatch_width() == 8 : bld.dispatch_width() == 16); const brw_reg_type type = (op == SHADER_OPCODE_TXF || op == SHADER_OPCODE_TXS ? BRW_REGISTER_TYPE_UD : BRW_REGISTER_TYPE_F); bld.MOV(retype(msg_end, type), lod); msg_end = offset(msg_end, bld, 1); } if (shadow_c.file != BAD_FILE) { if (op == SHADER_OPCODE_TEX && bld.dispatch_width() == 8) { /* There's no plain shadow compare message, so we use shadow * compare with a bias of 0.0. */ bld.MOV(msg_end, brw_imm_f(0.0f)); msg_end = offset(msg_end, bld, 1); } bld.MOV(msg_end, shadow_c); msg_end = offset(msg_end, bld, 1); } inst->opcode = op; inst->src[0] = reg_undef; inst->src[1] = surface; inst->src[2] = sampler; inst->resize_sources(3); inst->base_mrf = msg_begin.nr; inst->mlen = msg_end.nr - msg_begin.nr; inst->header_size = 1; } static void lower_sampler_logical_send_gen5(const fs_builder &bld, fs_inst *inst, opcode op, const fs_reg &coordinate, const fs_reg &shadow_c, const fs_reg &lod, const fs_reg &lod2, const fs_reg &sample_index, const fs_reg &surface, const fs_reg &sampler, unsigned coord_components, unsigned grad_components) { fs_reg message(MRF, 2, BRW_REGISTER_TYPE_F); fs_reg msg_coords = message; unsigned header_size = 0; if (inst->offset != 0) { /* The offsets set up by the visitor are in the m1 header, so we can't * go headerless. */ header_size = 1; message.nr--; } for (unsigned i = 0; i < coord_components; i++) bld.MOV(retype(offset(msg_coords, bld, i), coordinate.type), offset(coordinate, bld, i)); fs_reg msg_end = offset(msg_coords, bld, coord_components); fs_reg msg_lod = offset(msg_coords, bld, 4); if (shadow_c.file != BAD_FILE) { fs_reg msg_shadow = msg_lod; bld.MOV(msg_shadow, shadow_c); msg_lod = offset(msg_shadow, bld, 1); msg_end = msg_lod; } switch (op) { case SHADER_OPCODE_TXL: case FS_OPCODE_TXB: bld.MOV(msg_lod, lod); msg_end = offset(msg_lod, bld, 1); break; case SHADER_OPCODE_TXD: /** * P = u, v, r * dPdx = dudx, dvdx, drdx * dPdy = dudy, dvdy, drdy * * Load up these values: * - dudx dudy dvdx dvdy drdx drdy * - dPdx.x dPdy.x dPdx.y dPdy.y dPdx.z dPdy.z */ msg_end = msg_lod; for (unsigned i = 0; i < grad_components; i++) { bld.MOV(msg_end, offset(lod, bld, i)); msg_end = offset(msg_end, bld, 1); bld.MOV(msg_end, offset(lod2, bld, i)); msg_end = offset(msg_end, bld, 1); } break; case SHADER_OPCODE_TXS: msg_lod = retype(msg_end, BRW_REGISTER_TYPE_UD); bld.MOV(msg_lod, lod); msg_end = offset(msg_lod, bld, 1); break; case SHADER_OPCODE_TXF: msg_lod = offset(msg_coords, bld, 3); bld.MOV(retype(msg_lod, BRW_REGISTER_TYPE_UD), lod); msg_end = offset(msg_lod, bld, 1); break; case SHADER_OPCODE_TXF_CMS: msg_lod = offset(msg_coords, bld, 3); /* lod */ bld.MOV(retype(msg_lod, BRW_REGISTER_TYPE_UD), brw_imm_ud(0u)); /* sample index */ bld.MOV(retype(offset(msg_lod, bld, 1), BRW_REGISTER_TYPE_UD), sample_index); msg_end = offset(msg_lod, bld, 2); break; default: break; } inst->opcode = op; inst->src[0] = reg_undef; inst->src[1] = surface; inst->src[2] = sampler; inst->resize_sources(3); inst->base_mrf = message.nr; inst->mlen = msg_end.nr - message.nr; inst->header_size = header_size; /* Message length > MAX_SAMPLER_MESSAGE_SIZE disallowed by hardware. */ assert(inst->mlen <= MAX_SAMPLER_MESSAGE_SIZE); } static bool is_high_sampler(const struct gen_device_info *devinfo, const fs_reg &sampler) { if (devinfo->gen < 8 && !devinfo->is_haswell) return false; return sampler.file != IMM || sampler.ud >= 16; } static void lower_sampler_logical_send_gen7(const fs_builder &bld, fs_inst *inst, opcode op, const fs_reg &coordinate, const fs_reg &shadow_c, fs_reg lod, const fs_reg &lod2, const fs_reg &sample_index, const fs_reg &mcs, const fs_reg &surface, const fs_reg &sampler, const fs_reg &tg4_offset, unsigned coord_components, unsigned grad_components) { const gen_device_info *devinfo = bld.shader->devinfo; unsigned reg_width = bld.dispatch_width() / 8; unsigned header_size = 0, length = 0; fs_reg sources[MAX_SAMPLER_MESSAGE_SIZE]; for (unsigned i = 0; i < ARRAY_SIZE(sources); i++) sources[i] = bld.vgrf(BRW_REGISTER_TYPE_F); if (op == SHADER_OPCODE_TG4 || op == SHADER_OPCODE_TG4_OFFSET || inst->offset != 0 || inst->eot || op == SHADER_OPCODE_SAMPLEINFO || is_high_sampler(devinfo, sampler)) { /* For general texture offsets (no txf workaround), we need a header to * put them in. Note that we're only reserving space for it in the * message payload as it will be initialized implicitly by the * generator. * * TG4 needs to place its channel select in the header, for interaction * with ARB_texture_swizzle. The sampler index is only 4-bits, so for * larger sampler numbers we need to offset the Sampler State Pointer in * the header. */ header_size = 1; sources[0] = fs_reg(); length++; /* If we're requesting fewer than four channels worth of response, * and we have an explicit header, we need to set up the sampler * writemask. It's reversed from normal: 1 means "don't write". */ if (!inst->eot && regs_written(inst) != 4 * reg_width) { assert(regs_written(inst) % reg_width == 0); unsigned mask = ~((1 << (regs_written(inst) / reg_width)) - 1) & 0xf; inst->offset |= mask << 12; } } if (shadow_c.file != BAD_FILE) { bld.MOV(sources[length], shadow_c); length++; } bool coordinate_done = false; /* Set up the LOD info */ switch (op) { case FS_OPCODE_TXB: case SHADER_OPCODE_TXL: if (devinfo->gen >= 9 && op == SHADER_OPCODE_TXL && lod.is_zero()) { op = SHADER_OPCODE_TXL_LZ; break; } bld.MOV(sources[length], lod); length++; break; case SHADER_OPCODE_TXD: /* TXD should have been lowered in SIMD16 mode. */ assert(bld.dispatch_width() == 8); /* Load dPdx and the coordinate together: * [hdr], [ref], x, dPdx.x, dPdy.x, y, dPdx.y, dPdy.y, z, dPdx.z, dPdy.z */ for (unsigned i = 0; i < coord_components; i++) { bld.MOV(sources[length++], offset(coordinate, bld, i)); /* For cube map array, the coordinate is (u,v,r,ai) but there are * only derivatives for (u, v, r). */ if (i < grad_components) { bld.MOV(sources[length++], offset(lod, bld, i)); bld.MOV(sources[length++], offset(lod2, bld, i)); } } coordinate_done = true; break; case SHADER_OPCODE_TXS: bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_UD), lod); length++; break; case SHADER_OPCODE_TXF: /* Unfortunately, the parameters for LD are intermixed: u, lod, v, r. * On Gen9 they are u, v, lod, r */ bld.MOV(retype(sources[length++], BRW_REGISTER_TYPE_D), coordinate); if (devinfo->gen >= 9) { if (coord_components >= 2) { bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_D), offset(coordinate, bld, 1)); } else { sources[length] = brw_imm_d(0); } length++; } if (devinfo->gen >= 9 && lod.is_zero()) { op = SHADER_OPCODE_TXF_LZ; } else { bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_D), lod); length++; } for (unsigned i = devinfo->gen >= 9 ? 2 : 1; i < coord_components; i++) bld.MOV(retype(sources[length++], BRW_REGISTER_TYPE_D), offset(coordinate, bld, i)); coordinate_done = true; break; case SHADER_OPCODE_TXF_CMS: case SHADER_OPCODE_TXF_CMS_W: case SHADER_OPCODE_TXF_UMS: case SHADER_OPCODE_TXF_MCS: if (op == SHADER_OPCODE_TXF_UMS || op == SHADER_OPCODE_TXF_CMS || op == SHADER_OPCODE_TXF_CMS_W) { bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_UD), sample_index); length++; } if (op == SHADER_OPCODE_TXF_CMS || op == SHADER_OPCODE_TXF_CMS_W) { /* Data from the multisample control surface. */ bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_UD), mcs); length++; /* On Gen9+ we'll use ld2dms_w instead which has two registers for * the MCS data. */ if (op == SHADER_OPCODE_TXF_CMS_W) { bld.MOV(retype(sources[length], BRW_REGISTER_TYPE_UD), mcs.file == IMM ? mcs : offset(mcs, bld, 1)); length++; } } /* There is no offsetting for this message; just copy in the integer * texture coordinates. */ for (unsigned i = 0; i < coord_components; i++) bld.MOV(retype(sources[length++], BRW_REGISTER_TYPE_D), offset(coordinate, bld, i)); coordinate_done = true; break; case SHADER_OPCODE_TG4_OFFSET: /* More crazy intermixing */ for (unsigned i = 0; i < 2; i++) /* u, v */ bld.MOV(sources[length++], offset(coordinate, bld, i)); for (unsigned i = 0; i < 2; i++) /* offu, offv */ bld.MOV(retype(sources[length++], BRW_REGISTER_TYPE_D), offset(tg4_offset, bld, i)); if (coord_components == 3) /* r if present */ bld.MOV(sources[length++], offset(coordinate, bld, 2)); coordinate_done = true; break; default: break; } /* Set up the coordinate (except for cases where it was done above) */ if (!coordinate_done) { for (unsigned i = 0; i < coord_components; i++) bld.MOV(sources[length++], offset(coordinate, bld, i)); } int mlen; if (reg_width == 2) mlen = length * reg_width - header_size; else mlen = length * reg_width; const fs_reg src_payload = fs_reg(VGRF, bld.shader->alloc.allocate(mlen), BRW_REGISTER_TYPE_F); bld.LOAD_PAYLOAD(src_payload, sources, length, header_size); /* Generate the SEND. */ inst->opcode = op; inst->src[0] = src_payload; inst->src[1] = surface; inst->src[2] = sampler; inst->resize_sources(3); inst->mlen = mlen; inst->header_size = header_size; /* Message length > MAX_SAMPLER_MESSAGE_SIZE disallowed by hardware. */ assert(inst->mlen <= MAX_SAMPLER_MESSAGE_SIZE); } static void lower_sampler_logical_send(const fs_builder &bld, fs_inst *inst, opcode op) { const gen_device_info *devinfo = bld.shader->devinfo; const fs_reg &coordinate = inst->src[TEX_LOGICAL_SRC_COORDINATE]; const fs_reg &shadow_c = inst->src[TEX_LOGICAL_SRC_SHADOW_C]; const fs_reg &lod = inst->src[TEX_LOGICAL_SRC_LOD]; const fs_reg &lod2 = inst->src[TEX_LOGICAL_SRC_LOD2]; const fs_reg &sample_index = inst->src[TEX_LOGICAL_SRC_SAMPLE_INDEX]; const fs_reg &mcs = inst->src[TEX_LOGICAL_SRC_MCS]; const fs_reg &surface = inst->src[TEX_LOGICAL_SRC_SURFACE]; const fs_reg &sampler = inst->src[TEX_LOGICAL_SRC_SAMPLER]; const fs_reg &tg4_offset = inst->src[TEX_LOGICAL_SRC_TG4_OFFSET]; assert(inst->src[TEX_LOGICAL_SRC_COORD_COMPONENTS].file == IMM); const unsigned coord_components = inst->src[TEX_LOGICAL_SRC_COORD_COMPONENTS].ud; assert(inst->src[TEX_LOGICAL_SRC_GRAD_COMPONENTS].file == IMM); const unsigned grad_components = inst->src[TEX_LOGICAL_SRC_GRAD_COMPONENTS].ud; if (devinfo->gen >= 7) { lower_sampler_logical_send_gen7(bld, inst, op, coordinate, shadow_c, lod, lod2, sample_index, mcs, surface, sampler, tg4_offset, coord_components, grad_components); } else if (devinfo->gen >= 5) { lower_sampler_logical_send_gen5(bld, inst, op, coordinate, shadow_c, lod, lod2, sample_index, surface, sampler, coord_components, grad_components); } else { lower_sampler_logical_send_gen4(bld, inst, op, coordinate, shadow_c, lod, lod2, surface, sampler, coord_components, grad_components); } } /** * Initialize the header present in some typed and untyped surface * messages. */ static fs_reg emit_surface_header(const fs_builder &bld, const fs_reg &sample_mask) { fs_builder ubld = bld.exec_all().group(8, 0); const fs_reg dst = ubld.vgrf(BRW_REGISTER_TYPE_UD); ubld.MOV(dst, brw_imm_d(0)); ubld.MOV(component(dst, 7), sample_mask); return dst; } static void lower_surface_logical_send(const fs_builder &bld, fs_inst *inst, opcode op, const fs_reg &sample_mask) { /* Get the logical send arguments. */ const fs_reg &addr = inst->src[0]; const fs_reg &src = inst->src[1]; const fs_reg &surface = inst->src[2]; const UNUSED fs_reg &dims = inst->src[3]; const fs_reg &arg = inst->src[4]; /* Calculate the total number of components of the payload. */ const unsigned addr_sz = inst->components_read(0); const unsigned src_sz = inst->components_read(1); const unsigned header_sz = (sample_mask.file == BAD_FILE ? 0 : 1); const unsigned sz = header_sz + addr_sz + src_sz; /* Allocate space for the payload. */ fs_reg *const components = new fs_reg[sz]; const fs_reg payload = bld.vgrf(BRW_REGISTER_TYPE_UD, sz); unsigned n = 0; /* Construct the payload. */ if (header_sz) components[n++] = emit_surface_header(bld, sample_mask); for (unsigned i = 0; i < addr_sz; i++) components[n++] = offset(addr, bld, i); for (unsigned i = 0; i < src_sz; i++) components[n++] = offset(src, bld, i); bld.LOAD_PAYLOAD(payload, components, sz, header_sz); /* Update the original instruction. */ inst->opcode = op; inst->mlen = header_sz + (addr_sz + src_sz) * inst->exec_size / 8; inst->header_size = header_sz; inst->src[0] = payload; inst->src[1] = surface; inst->src[2] = arg; inst->resize_sources(3); delete[] components; } static void lower_varying_pull_constant_logical_send(const fs_builder &bld, fs_inst *inst) { const gen_device_info *devinfo = bld.shader->devinfo; if (devinfo->gen >= 7) { /* We are switching the instruction from an ALU-like instruction to a * send-from-grf instruction. Since sends can't handle strides or * source modifiers, we have to make a copy of the offset source. */ fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_UD); bld.MOV(tmp, inst->src[1]); inst->src[1] = tmp; inst->opcode = FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7; } else { const fs_reg payload(MRF, FIRST_PULL_LOAD_MRF(devinfo->gen), BRW_REGISTER_TYPE_UD); bld.MOV(byte_offset(payload, REG_SIZE), inst->src[1]); inst->opcode = FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN4; inst->resize_sources(1); inst->base_mrf = payload.nr; inst->header_size = 1; inst->mlen = 1 + inst->exec_size / 8; } } static void lower_math_logical_send(const fs_builder &bld, fs_inst *inst) { assert(bld.shader->devinfo->gen < 6); inst->base_mrf = 2; inst->mlen = inst->sources * inst->exec_size / 8; if (inst->sources > 1) { /* From the Ironlake PRM, Volume 4, Part 1, Section 6.1.13 * "Message Payload": * * "Operand0[7]. For the INT DIV functions, this operand is the * denominator." * ... * "Operand1[7]. For the INT DIV functions, this operand is the * numerator." */ const bool is_int_div = inst->opcode != SHADER_OPCODE_POW; const fs_reg src0 = is_int_div ? inst->src[1] : inst->src[0]; const fs_reg src1 = is_int_div ? inst->src[0] : inst->src[1]; inst->resize_sources(1); inst->src[0] = src0; assert(inst->exec_size == 8); bld.MOV(fs_reg(MRF, inst->base_mrf + 1, src1.type), src1); } } bool fs_visitor::lower_logical_sends() { bool progress = false; foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { const fs_builder ibld(this, block, inst); switch (inst->opcode) { case FS_OPCODE_FB_WRITE_LOGICAL: assert(stage == MESA_SHADER_FRAGMENT); lower_fb_write_logical_send(ibld, inst, brw_wm_prog_data(prog_data), (const brw_wm_prog_key *)key, payload); break; case FS_OPCODE_FB_READ_LOGICAL: lower_fb_read_logical_send(ibld, inst); break; case SHADER_OPCODE_TEX_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TEX); break; case SHADER_OPCODE_TXD_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXD); break; case SHADER_OPCODE_TXF_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF); break; case SHADER_OPCODE_TXL_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXL); break; case SHADER_OPCODE_TXS_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXS); break; case FS_OPCODE_TXB_LOGICAL: lower_sampler_logical_send(ibld, inst, FS_OPCODE_TXB); break; case SHADER_OPCODE_TXF_CMS_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_CMS); break; case SHADER_OPCODE_TXF_CMS_W_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_CMS_W); break; case SHADER_OPCODE_TXF_UMS_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_UMS); break; case SHADER_OPCODE_TXF_MCS_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_MCS); break; case SHADER_OPCODE_LOD_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_LOD); break; case SHADER_OPCODE_TG4_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TG4); break; case SHADER_OPCODE_TG4_OFFSET_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TG4_OFFSET); break; case SHADER_OPCODE_SAMPLEINFO_LOGICAL: lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_SAMPLEINFO); break; case SHADER_OPCODE_UNTYPED_SURFACE_READ_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_UNTYPED_SURFACE_READ, fs_reg()); break; case SHADER_OPCODE_UNTYPED_SURFACE_WRITE_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_UNTYPED_SURFACE_WRITE, ibld.sample_mask_reg()); break; case SHADER_OPCODE_UNTYPED_ATOMIC_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_UNTYPED_ATOMIC, ibld.sample_mask_reg()); break; case SHADER_OPCODE_TYPED_SURFACE_READ_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_TYPED_SURFACE_READ, brw_imm_d(0xffff)); break; case SHADER_OPCODE_TYPED_SURFACE_WRITE_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_TYPED_SURFACE_WRITE, ibld.sample_mask_reg()); break; case SHADER_OPCODE_TYPED_ATOMIC_LOGICAL: lower_surface_logical_send(ibld, inst, SHADER_OPCODE_TYPED_ATOMIC, ibld.sample_mask_reg()); break; case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_LOGICAL: lower_varying_pull_constant_logical_send(ibld, inst); break; case SHADER_OPCODE_RCP: case SHADER_OPCODE_RSQ: case SHADER_OPCODE_SQRT: case SHADER_OPCODE_EXP2: case SHADER_OPCODE_LOG2: case SHADER_OPCODE_SIN: case SHADER_OPCODE_COS: case SHADER_OPCODE_POW: case SHADER_OPCODE_INT_QUOTIENT: case SHADER_OPCODE_INT_REMAINDER: /* The math opcodes are overloaded for the send-like and * expression-like instructions which seems kind of icky. Gen6+ has * a native (but rather quirky) MATH instruction so we don't need to * do anything here. On Gen4-5 we'll have to lower the Gen6-like * logical instructions (which we can easily recognize because they * have mlen = 0) into send-like virtual instructions. */ if (devinfo->gen < 6 && inst->mlen == 0) { lower_math_logical_send(ibld, inst); break; } else { continue; } default: continue; } progress = true; } if (progress) invalidate_live_intervals(); return progress; } /** * Get the closest allowed SIMD width for instruction \p inst accounting for * some common regioning and execution control restrictions that apply to FPU * instructions. These restrictions don't necessarily have any relevance to * instructions not executed by the FPU pipeline like extended math, control * flow or send message instructions. * * For virtual opcodes it's really up to the instruction -- In some cases * (e.g. where a virtual instruction unrolls into a simple sequence of FPU * instructions) it may simplify virtual instruction lowering if we can * enforce FPU-like regioning restrictions already on the virtual instruction, * in other cases (e.g. virtual send-like instructions) this may be * excessively restrictive. */ static unsigned get_fpu_lowered_simd_width(const struct gen_device_info *devinfo, const fs_inst *inst) { /* Maximum execution size representable in the instruction controls. */ unsigned max_width = MIN2(32, inst->exec_size); /* According to the PRMs: * "A. In Direct Addressing mode, a source cannot span more than 2 * adjacent GRF registers. * B. A destination cannot span more than 2 adjacent GRF registers." * * Look for the source or destination with the largest register region * which is the one that is going to limit the overall execution size of * the instruction due to this rule. */ unsigned reg_count = DIV_ROUND_UP(inst->size_written, REG_SIZE); for (unsigned i = 0; i < inst->sources; i++) reg_count = MAX2(reg_count, DIV_ROUND_UP(inst->size_read(i), REG_SIZE)); /* Calculate the maximum execution size of the instruction based on the * factor by which it goes over the hardware limit of 2 GRFs. */ if (reg_count > 2) max_width = MIN2(max_width, inst->exec_size / DIV_ROUND_UP(reg_count, 2)); /* According to the IVB PRMs: * "When destination spans two registers, the source MUST span two * registers. The exception to the above rule: * * - When source is scalar, the source registers are not incremented. * - When source is packed integer Word and destination is packed * integer DWord, the source register is not incremented but the * source sub register is incremented." * * The hardware specs from Gen4 to Gen7.5 mention similar regioning * restrictions. The code below intentionally doesn't check whether the * destination type is integer because empirically the hardware doesn't * seem to care what the actual type is as long as it's dword-aligned. */ if (devinfo->gen < 8) { for (unsigned i = 0; i < inst->sources; i++) { /* IVB implements DF scalars as <0;2,1> regions. */ const bool is_scalar_exception = is_uniform(inst->src[i]) && (devinfo->is_haswell || type_sz(inst->src[i].type) != 8); const bool is_packed_word_exception = type_sz(inst->dst.type) == 4 && inst->dst.stride == 1 && type_sz(inst->src[i].type) == 2 && inst->src[i].stride == 1; if (inst->size_written > REG_SIZE && inst->size_read(i) != 0 && inst->size_read(i) <= REG_SIZE && !is_scalar_exception && !is_packed_word_exception) { const unsigned reg_count = DIV_ROUND_UP(inst->size_written, REG_SIZE); max_width = MIN2(max_width, inst->exec_size / reg_count); } } } /* From the IVB PRMs: * "When an instruction is SIMD32, the low 16 bits of the execution mask * are applied for both halves of the SIMD32 instruction. If different * execution mask channels are required, split the instruction into two * SIMD16 instructions." * * There is similar text in the HSW PRMs. Gen4-6 don't even implement * 32-wide control flow support in hardware and will behave similarly. */ if (devinfo->gen < 8 && !inst->force_writemask_all) max_width = MIN2(max_width, 16); /* From the IVB PRMs (applies to HSW too): * "Instructions with condition modifiers must not use SIMD32." * * From the BDW PRMs (applies to later hardware too): * "Ternary instruction with condition modifiers must not use SIMD32." */ if (inst->conditional_mod && (devinfo->gen < 8 || inst->is_3src(devinfo))) max_width = MIN2(max_width, 16); /* From the IVB PRMs (applies to other devices that don't have the * gen_device_info::supports_simd16_3src flag set): * "In Align16 access mode, SIMD16 is not allowed for DW operations and * SIMD8 is not allowed for DF operations." */ if (inst->is_3src(devinfo) && !devinfo->supports_simd16_3src) max_width = MIN2(max_width, inst->exec_size / reg_count); /* Pre-Gen8 EUs are hardwired to use the QtrCtrl+1 (where QtrCtrl is * the 8-bit quarter of the execution mask signals specified in the * instruction control fields) for the second compressed half of any * single-precision instruction (for double-precision instructions * it's hardwired to use NibCtrl+1, at least on HSW), which means that * the EU will apply the wrong execution controls for the second * sequential GRF write if the number of channels per GRF is not exactly * eight in single-precision mode (or four in double-float mode). * * In this situation we calculate the maximum size of the split * instructions so they only ever write to a single register. */ if (devinfo->gen < 8 && inst->size_written > REG_SIZE && !inst->force_writemask_all) { const unsigned channels_per_grf = inst->exec_size / DIV_ROUND_UP(inst->size_written, REG_SIZE); const unsigned exec_type_size = get_exec_type_size(inst); assert(exec_type_size); /* The hardware shifts exactly 8 channels per compressed half of the * instruction in single-precision mode and exactly 4 in double-precision. */ if (channels_per_grf != (exec_type_size == 8 ? 4 : 8)) max_width = MIN2(max_width, channels_per_grf); /* Lower all non-force_writemask_all DF instructions to SIMD4 on IVB/BYT * because HW applies the same channel enable signals to both halves of * the compressed instruction which will be just wrong under * non-uniform control flow. */ if (devinfo->gen == 7 && !devinfo->is_haswell && (exec_type_size == 8 || type_sz(inst->dst.type) == 8)) max_width = MIN2(max_width, 4); } /* Only power-of-two execution sizes are representable in the instruction * control fields. */ return 1 << _mesa_logbase2(max_width); } /** * Get the maximum allowed SIMD width for instruction \p inst accounting for * various payload size restrictions that apply to sampler message * instructions. * * This is only intended to provide a maximum theoretical bound for the * execution size of the message based on the number of argument components * alone, which in most cases will determine whether the SIMD8 or SIMD16 * variant of the message can be used, though some messages may have * additional restrictions not accounted for here (e.g. pre-ILK hardware uses * the message length to determine the exact SIMD width and argument count, * which makes a number of sampler message combinations impossible to * represent). */ static unsigned get_sampler_lowered_simd_width(const struct gen_device_info *devinfo, const fs_inst *inst) { /* Calculate the number of coordinate components that have to be present * assuming that additional arguments follow the texel coordinates in the * message payload. On IVB+ there is no need for padding, on ILK-SNB we * need to pad to four or three components depending on the message, * pre-ILK we need to pad to at most three components. */ const unsigned req_coord_components = (devinfo->gen >= 7 || !inst->components_read(TEX_LOGICAL_SRC_COORDINATE)) ? 0 : (devinfo->gen >= 5 && inst->opcode != SHADER_OPCODE_TXF_LOGICAL && inst->opcode != SHADER_OPCODE_TXF_CMS_LOGICAL) ? 4 : 3; /* On Gen9+ the LOD argument is for free if we're able to use the LZ * variant of the TXL or TXF message. */ const bool implicit_lod = devinfo->gen >= 9 && (inst->opcode == SHADER_OPCODE_TXL || inst->opcode == SHADER_OPCODE_TXF) && inst->src[TEX_LOGICAL_SRC_LOD].is_zero(); /* Calculate the total number of argument components that need to be passed * to the sampler unit. */ const unsigned num_payload_components = MAX2(inst->components_read(TEX_LOGICAL_SRC_COORDINATE), req_coord_components) + inst->components_read(TEX_LOGICAL_SRC_SHADOW_C) + (implicit_lod ? 0 : inst->components_read(TEX_LOGICAL_SRC_LOD)) + inst->components_read(TEX_LOGICAL_SRC_LOD2) + inst->components_read(TEX_LOGICAL_SRC_SAMPLE_INDEX) + (inst->opcode == SHADER_OPCODE_TG4_OFFSET_LOGICAL ? inst->components_read(TEX_LOGICAL_SRC_TG4_OFFSET) : 0) + inst->components_read(TEX_LOGICAL_SRC_MCS); /* SIMD16 messages with more than five arguments exceed the maximum message * size supported by the sampler, regardless of whether a header is * provided or not. */ return MIN2(inst->exec_size, num_payload_components > MAX_SAMPLER_MESSAGE_SIZE / 2 ? 8 : 16); } /** * Get the closest native SIMD width supported by the hardware for instruction * \p inst. The instruction will be left untouched by * fs_visitor::lower_simd_width() if the returned value is equal to the * original execution size. */ static unsigned get_lowered_simd_width(const struct gen_device_info *devinfo, const fs_inst *inst) { switch (inst->opcode) { case BRW_OPCODE_MOV: case BRW_OPCODE_SEL: case BRW_OPCODE_NOT: case BRW_OPCODE_AND: case BRW_OPCODE_OR: case BRW_OPCODE_XOR: case BRW_OPCODE_SHR: case BRW_OPCODE_SHL: case BRW_OPCODE_ASR: case BRW_OPCODE_CMPN: case BRW_OPCODE_CSEL: case BRW_OPCODE_F32TO16: case BRW_OPCODE_F16TO32: case BRW_OPCODE_BFREV: case BRW_OPCODE_BFE: case BRW_OPCODE_ADD: case BRW_OPCODE_MUL: case BRW_OPCODE_AVG: case BRW_OPCODE_FRC: case BRW_OPCODE_RNDU: case BRW_OPCODE_RNDD: case BRW_OPCODE_RNDE: case BRW_OPCODE_RNDZ: case BRW_OPCODE_LZD: case BRW_OPCODE_FBH: case BRW_OPCODE_FBL: case BRW_OPCODE_CBIT: case BRW_OPCODE_SAD2: case BRW_OPCODE_MAD: case BRW_OPCODE_LRP: case FS_OPCODE_PACK: return get_fpu_lowered_simd_width(devinfo, inst); case BRW_OPCODE_CMP: { /* The Ivybridge/BayTrail WaCMPInstFlagDepClearedEarly workaround says that * when the destination is a GRF the dependency-clear bit on the flag * register is cleared early. * * Suggested workarounds are to disable coissuing CMP instructions * or to split CMP(16) instructions into two CMP(8) instructions. * * We choose to split into CMP(8) instructions since disabling * coissuing would affect CMP instructions not otherwise affected by * the errata. */ const unsigned max_width = (devinfo->gen == 7 && !devinfo->is_haswell && !inst->dst.is_null() ? 8 : ~0); return MIN2(max_width, get_fpu_lowered_simd_width(devinfo, inst)); } case BRW_OPCODE_BFI1: case BRW_OPCODE_BFI2: /* The Haswell WaForceSIMD8ForBFIInstruction workaround says that we * should * "Force BFI instructions to be executed always in SIMD8." */ return MIN2(devinfo->is_haswell ? 8 : ~0u, get_fpu_lowered_simd_width(devinfo, inst)); case BRW_OPCODE_IF: assert(inst->src[0].file == BAD_FILE || inst->exec_size <= 16); return inst->exec_size; case SHADER_OPCODE_RCP: case SHADER_OPCODE_RSQ: case SHADER_OPCODE_SQRT: case SHADER_OPCODE_EXP2: case SHADER_OPCODE_LOG2: case SHADER_OPCODE_SIN: case SHADER_OPCODE_COS: /* Unary extended math instructions are limited to SIMD8 on Gen4 and * Gen6. */ return (devinfo->gen >= 7 ? MIN2(16, inst->exec_size) : devinfo->gen == 5 || devinfo->is_g4x ? MIN2(16, inst->exec_size) : MIN2(8, inst->exec_size)); case SHADER_OPCODE_POW: /* SIMD16 is only allowed on Gen7+. */ return (devinfo->gen >= 7 ? MIN2(16, inst->exec_size) : MIN2(8, inst->exec_size)); case SHADER_OPCODE_INT_QUOTIENT: case SHADER_OPCODE_INT_REMAINDER: /* Integer division is limited to SIMD8 on all generations. */ return MIN2(8, inst->exec_size); case FS_OPCODE_LINTERP: case FS_OPCODE_GET_BUFFER_SIZE: case FS_OPCODE_DDX_COARSE: case FS_OPCODE_DDX_FINE: case FS_OPCODE_DDY_COARSE: case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD: case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7: case FS_OPCODE_PACK_HALF_2x16_SPLIT: case FS_OPCODE_UNPACK_HALF_2x16_SPLIT_X: case FS_OPCODE_UNPACK_HALF_2x16_SPLIT_Y: case FS_OPCODE_INTERPOLATE_AT_SAMPLE: case FS_OPCODE_INTERPOLATE_AT_SHARED_OFFSET: case FS_OPCODE_INTERPOLATE_AT_PER_SLOT_OFFSET: return MIN2(16, inst->exec_size); case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_LOGICAL: /* Pre-ILK hardware doesn't have a SIMD8 variant of the texel fetch * message used to implement varying pull constant loads, so expand it * to SIMD16. An alternative with longer message payload length but * shorter return payload would be to use the SIMD8 sampler message that * takes (header, u, v, r) as parameters instead of (header, u). */ return (devinfo->gen == 4 ? 16 : MIN2(16, inst->exec_size)); case FS_OPCODE_DDY_FINE: /* The implementation of this virtual opcode may require emitting * compressed Align16 instructions, which are severely limited on some * generations. * * From the Ivy Bridge PRM, volume 4 part 3, section 3.3.9 (Register * Region Restrictions): * * "In Align16 access mode, SIMD16 is not allowed for DW operations * and SIMD8 is not allowed for DF operations." * * In this context, "DW operations" means "operations acting on 32-bit * values", so it includes operations on floats. * * Gen4 has a similar restriction. From the i965 PRM, section 11.5.3 * (Instruction Compression -> Rules and Restrictions): * * "A compressed instruction must be in Align1 access mode. Align16 * mode instructions cannot be compressed." * * Similar text exists in the g45 PRM. * * Empirically, compressed align16 instructions using odd register * numbers don't appear to work on Sandybridge either. */ return (devinfo->gen == 4 || devinfo->gen == 6 || (devinfo->gen == 7 && !devinfo->is_haswell) ? MIN2(8, inst->exec_size) : MIN2(16, inst->exec_size)); case SHADER_OPCODE_MULH: /* MULH is lowered to the MUL/MACH sequence using the accumulator, which * is 8-wide on Gen7+. */ return (devinfo->gen >= 7 ? 8 : get_fpu_lowered_simd_width(devinfo, inst)); case FS_OPCODE_FB_WRITE_LOGICAL: /* Gen6 doesn't support SIMD16 depth writes but we cannot handle them * here. */ assert(devinfo->gen != 6 || inst->src[FB_WRITE_LOGICAL_SRC_SRC_DEPTH].file == BAD_FILE || inst->exec_size == 8); /* Dual-source FB writes are unsupported in SIMD16 mode. */ return (inst->src[FB_WRITE_LOGICAL_SRC_COLOR1].file != BAD_FILE ? 8 : MIN2(16, inst->exec_size)); case FS_OPCODE_FB_READ_LOGICAL: return MIN2(16, inst->exec_size); case SHADER_OPCODE_TEX_LOGICAL: case SHADER_OPCODE_TXF_CMS_LOGICAL: case SHADER_OPCODE_TXF_UMS_LOGICAL: case SHADER_OPCODE_TXF_MCS_LOGICAL: case SHADER_OPCODE_LOD_LOGICAL: case SHADER_OPCODE_TG4_LOGICAL: case SHADER_OPCODE_SAMPLEINFO_LOGICAL: case SHADER_OPCODE_TXF_CMS_W_LOGICAL: case SHADER_OPCODE_TG4_OFFSET_LOGICAL: return get_sampler_lowered_simd_width(devinfo, inst); case SHADER_OPCODE_TXD_LOGICAL: /* TXD is unsupported in SIMD16 mode. */ return 8; case SHADER_OPCODE_TXL_LOGICAL: case FS_OPCODE_TXB_LOGICAL: /* Only one execution size is representable pre-ILK depending on whether * the shadow reference argument is present. */ if (devinfo->gen == 4) return inst->src[TEX_LOGICAL_SRC_SHADOW_C].file == BAD_FILE ? 16 : 8; else return get_sampler_lowered_simd_width(devinfo, inst); case SHADER_OPCODE_TXF_LOGICAL: case SHADER_OPCODE_TXS_LOGICAL: /* Gen4 doesn't have SIMD8 variants for the RESINFO and LD-with-LOD * messages. Use SIMD16 instead. */ if (devinfo->gen == 4) return 16; else return get_sampler_lowered_simd_width(devinfo, inst); case SHADER_OPCODE_TYPED_ATOMIC_LOGICAL: case SHADER_OPCODE_TYPED_SURFACE_READ_LOGICAL: case SHADER_OPCODE_TYPED_SURFACE_WRITE_LOGICAL: return 8; case SHADER_OPCODE_UNTYPED_ATOMIC_LOGICAL: case SHADER_OPCODE_UNTYPED_SURFACE_READ_LOGICAL: case SHADER_OPCODE_UNTYPED_SURFACE_WRITE_LOGICAL: return MIN2(16, inst->exec_size); case SHADER_OPCODE_URB_READ_SIMD8: case SHADER_OPCODE_URB_READ_SIMD8_PER_SLOT: case SHADER_OPCODE_URB_WRITE_SIMD8: case SHADER_OPCODE_URB_WRITE_SIMD8_PER_SLOT: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED: case SHADER_OPCODE_URB_WRITE_SIMD8_MASKED_PER_SLOT: return MIN2(8, inst->exec_size); case SHADER_OPCODE_MOV_INDIRECT: { /* From IVB and HSW PRMs: * * "2.When the destination requires two registers and the sources are * indirect, the sources must use 1x1 regioning mode. * * In case of DF instructions in HSW/IVB, the exec_size is limited by * the EU decompression logic not handling VxH indirect addressing * correctly. */ const unsigned max_size = (devinfo->gen >= 8 ? 2 : 1) * REG_SIZE; /* Prior to Broadwell, we only have 8 address subregisters. */ return MIN3(devinfo->gen >= 8 ? 16 : 8, max_size / (inst->dst.stride * type_sz(inst->dst.type)), inst->exec_size); } case SHADER_OPCODE_LOAD_PAYLOAD: { const unsigned reg_count = DIV_ROUND_UP(inst->dst.component_size(inst->exec_size), REG_SIZE); if (reg_count > 2) { /* Only LOAD_PAYLOAD instructions with per-channel destination region * can be easily lowered (which excludes headers and heterogeneous * types). */ assert(!inst->header_size); for (unsigned i = 0; i < inst->sources; i++) assert(type_sz(inst->dst.type) == type_sz(inst->src[i].type) || inst->src[i].file == BAD_FILE); return inst->exec_size / DIV_ROUND_UP(reg_count, 2); } else { return inst->exec_size; } } default: return inst->exec_size; } } /** * Return true if splitting out the group of channels of instruction \p inst * given by lbld.group() requires allocating a temporary for the i-th source * of the lowered instruction. */ static inline bool needs_src_copy(const fs_builder &lbld, const fs_inst *inst, unsigned i) { return !(is_periodic(inst->src[i], lbld.dispatch_width()) || (inst->components_read(i) == 1 && lbld.dispatch_width() <= inst->exec_size)); } /** * Extract the data that would be consumed by the channel group given by * lbld.group() from the i-th source region of instruction \p inst and return * it as result in packed form. If any copy instructions are required they * will be emitted before the given \p inst in \p block. */ static fs_reg emit_unzip(const fs_builder &lbld, bblock_t *block, fs_inst *inst, unsigned i) { /* Specified channel group from the source region. */ const fs_reg src = horiz_offset(inst->src[i], lbld.group()); if (needs_src_copy(lbld, inst, i)) { /* Builder of the right width to perform the copy avoiding uninitialized * data if the lowered execution size is greater than the original * execution size of the instruction. */ const fs_builder cbld = lbld.group(MIN2(lbld.dispatch_width(), inst->exec_size), 0); const fs_reg tmp = lbld.vgrf(inst->src[i].type, inst->components_read(i)); for (unsigned k = 0; k < inst->components_read(i); ++k) cbld.at(block, inst) .MOV(offset(tmp, lbld, k), offset(src, inst->exec_size, k)); return tmp; } else if (is_periodic(inst->src[i], lbld.dispatch_width())) { /* The source is invariant for all dispatch_width-wide groups of the * original region. */ return inst->src[i]; } else { /* We can just point the lowered instruction at the right channel group * from the original region. */ return src; } } /** * Return true if splitting out the group of channels of instruction \p inst * given by lbld.group() requires allocating a temporary for the destination * of the lowered instruction and copying the data back to the original * destination region. */ static inline bool needs_dst_copy(const fs_builder &lbld, const fs_inst *inst) { /* If the instruction writes more than one component we'll have to shuffle * the results of multiple lowered instructions in order to make sure that * they end up arranged correctly in the original destination region. */ if (inst->size_written > inst->dst.component_size(inst->exec_size)) return true; /* If the lowered execution size is larger than the original the result of * the instruction won't fit in the original destination, so we'll have to * allocate a temporary in any case. */ if (lbld.dispatch_width() > inst->exec_size) return true; for (unsigned i = 0; i < inst->sources; i++) { /* If we already made a copy of the source for other reasons there won't * be any overlap with the destination. */ if (needs_src_copy(lbld, inst, i)) continue; /* In order to keep the logic simple we emit a copy whenever the * destination region doesn't exactly match an overlapping source, which * may point at the source and destination not being aligned group by * group which could cause one of the lowered instructions to overwrite * the data read from the same source by other lowered instructions. */ if (regions_overlap(inst->dst, inst->size_written, inst->src[i], inst->size_read(i)) && !inst->dst.equals(inst->src[i])) return true; } return false; } /** * Insert data from a packed temporary into the channel group given by * lbld.group() of the destination region of instruction \p inst and return * the temporary as result. If any copy instructions are required they will * be emitted around the given \p inst in \p block. */ static fs_reg emit_zip(const fs_builder &lbld, bblock_t *block, fs_inst *inst) { /* Builder of the right width to perform the copy avoiding uninitialized * data if the lowered execution size is greater than the original * execution size of the instruction. */ const fs_builder cbld = lbld.group(MIN2(lbld.dispatch_width(), inst->exec_size), 0); /* Specified channel group from the destination region. */ const fs_reg dst = horiz_offset(inst->dst, lbld.group()); const unsigned dst_size = inst->size_written / inst->dst.component_size(inst->exec_size); if (needs_dst_copy(lbld, inst)) { const fs_reg tmp = lbld.vgrf(inst->dst.type, dst_size); if (inst->predicate) { /* Handle predication by copying the original contents of * the destination into the temporary before emitting the * lowered instruction. */ for (unsigned k = 0; k < dst_size; ++k) cbld.at(block, inst) .MOV(offset(tmp, lbld, k), offset(dst, inst->exec_size, k)); } for (unsigned k = 0; k < dst_size; ++k) cbld.at(block, inst->next) .MOV(offset(dst, inst->exec_size, k), offset(tmp, lbld, k)); return tmp; } else { /* No need to allocate a temporary for the lowered instruction, just * take the right group of channels from the original region. */ return dst; } } bool fs_visitor::lower_simd_width() { bool progress = false; foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { const unsigned lower_width = get_lowered_simd_width(devinfo, inst); if (lower_width != inst->exec_size) { /* Builder matching the original instruction. We may also need to * emit an instruction of width larger than the original, set the * execution size of the builder to the highest of both for now so * we're sure that both cases can be handled. */ const unsigned max_width = MAX2(inst->exec_size, lower_width); const fs_builder ibld = bld.at(block, inst) .exec_all(inst->force_writemask_all) .group(max_width, inst->group / max_width); /* Split the copies in chunks of the execution width of either the * original or the lowered instruction, whichever is lower. */ const unsigned n = DIV_ROUND_UP(inst->exec_size, lower_width); const unsigned dst_size = inst->size_written / inst->dst.component_size(inst->exec_size); assert(!inst->writes_accumulator && !inst->mlen); for (unsigned i = 0; i < n; i++) { /* Emit a copy of the original instruction with the lowered width. * If the EOT flag was set throw it away except for the last * instruction to avoid killing the thread prematurely. */ fs_inst split_inst = *inst; split_inst.exec_size = lower_width; split_inst.eot = inst->eot && i == n - 1; /* Select the correct channel enables for the i-th group, then * transform the sources and destination and emit the lowered * instruction. */ const fs_builder lbld = ibld.group(lower_width, i); for (unsigned j = 0; j < inst->sources; j++) split_inst.src[j] = emit_unzip(lbld, block, inst, j); split_inst.dst = emit_zip(lbld, block, inst); split_inst.size_written = split_inst.dst.component_size(lower_width) * dst_size; lbld.emit(split_inst); } inst->remove(block); progress = true; } } if (progress) invalidate_live_intervals(); return progress; } void fs_visitor::dump_instructions() { dump_instructions(NULL); } void fs_visitor::dump_instructions(const char *name) { FILE *file = stderr; if (name && geteuid() != 0) { file = fopen(name, "w"); if (!file) file = stderr; } if (cfg) { calculate_register_pressure(); int ip = 0, max_pressure = 0; foreach_block_and_inst(block, backend_instruction, inst, cfg) { max_pressure = MAX2(max_pressure, regs_live_at_ip[ip]); fprintf(file, "{%3d} %4d: ", regs_live_at_ip[ip], ip); dump_instruction(inst, file); ip++; } fprintf(file, "Maximum %3d registers live at once.\n", max_pressure); } else { int ip = 0; foreach_in_list(backend_instruction, inst, &instructions) { fprintf(file, "%4d: ", ip++); dump_instruction(inst, file); } } if (file != stderr) { fclose(file); } } void fs_visitor::dump_instruction(backend_instruction *be_inst) { dump_instruction(be_inst, stderr); } void fs_visitor::dump_instruction(backend_instruction *be_inst, FILE *file) { fs_inst *inst = (fs_inst *)be_inst; if (inst->predicate) { fprintf(file, "(%cf0.%d) ", inst->predicate_inverse ? '-' : '+', inst->flag_subreg); } fprintf(file, "%s", brw_instruction_name(devinfo, inst->opcode)); if (inst->saturate) fprintf(file, ".sat"); if (inst->conditional_mod) { fprintf(file, "%s", conditional_modifier[inst->conditional_mod]); if (!inst->predicate && (devinfo->gen < 5 || (inst->opcode != BRW_OPCODE_SEL && inst->opcode != BRW_OPCODE_IF && inst->opcode != BRW_OPCODE_WHILE))) { fprintf(file, ".f0.%d", inst->flag_subreg); } } fprintf(file, "(%d) ", inst->exec_size); if (inst->mlen) { fprintf(file, "(mlen: %d) ", inst->mlen); } if (inst->eot) { fprintf(file, "(EOT) "); } switch (inst->dst.file) { case VGRF: fprintf(file, "vgrf%d", inst->dst.nr); break; case FIXED_GRF: fprintf(file, "g%d", inst->dst.nr); break; case MRF: fprintf(file, "m%d", inst->dst.nr); break; case BAD_FILE: fprintf(file, "(null)"); break; case UNIFORM: fprintf(file, "***u%d***", inst->dst.nr); break; case ATTR: fprintf(file, "***attr%d***", inst->dst.nr); break; case ARF: switch (inst->dst.nr) { case BRW_ARF_NULL: fprintf(file, "null"); break; case BRW_ARF_ADDRESS: fprintf(file, "a0.%d", inst->dst.subnr); break; case BRW_ARF_ACCUMULATOR: fprintf(file, "acc%d", inst->dst.subnr); break; case BRW_ARF_FLAG: fprintf(file, "f%d.%d", inst->dst.nr & 0xf, inst->dst.subnr); break; default: fprintf(file, "arf%d.%d", inst->dst.nr & 0xf, inst->dst.subnr); break; } break; case IMM: unreachable("not reached"); } if (inst->dst.offset || (inst->dst.file == VGRF && alloc.sizes[inst->dst.nr] * REG_SIZE != inst->size_written)) { const unsigned reg_size = (inst->dst.file == UNIFORM ? 4 : REG_SIZE); fprintf(file, "+%d.%d", inst->dst.offset / reg_size, inst->dst.offset % reg_size); } if (inst->dst.stride != 1) fprintf(file, "<%u>", inst->dst.stride); fprintf(file, ":%s, ", brw_reg_type_to_letters(inst->dst.type)); for (int i = 0; i < inst->sources; i++) { if (inst->src[i].negate) fprintf(file, "-"); if (inst->src[i].abs) fprintf(file, "|"); switch (inst->src[i].file) { case VGRF: fprintf(file, "vgrf%d", inst->src[i].nr); break; case FIXED_GRF: fprintf(file, "g%d", inst->src[i].nr); break; case MRF: fprintf(file, "***m%d***", inst->src[i].nr); break; case ATTR: fprintf(file, "attr%d", inst->src[i].nr); break; case UNIFORM: fprintf(file, "u%d", inst->src[i].nr); break; case BAD_FILE: fprintf(file, "(null)"); break; case IMM: switch (inst->src[i].type) { case BRW_REGISTER_TYPE_F: fprintf(file, "%-gf", inst->src[i].f); break; case BRW_REGISTER_TYPE_DF: fprintf(file, "%fdf", inst->src[i].df); break; case BRW_REGISTER_TYPE_W: case BRW_REGISTER_TYPE_D: fprintf(file, "%dd", inst->src[i].d); break; case BRW_REGISTER_TYPE_UW: case BRW_REGISTER_TYPE_UD: fprintf(file, "%uu", inst->src[i].ud); break; case BRW_REGISTER_TYPE_VF: fprintf(file, "[%-gF, %-gF, %-gF, %-gF]", brw_vf_to_float((inst->src[i].ud >> 0) & 0xff), brw_vf_to_float((inst->src[i].ud >> 8) & 0xff), brw_vf_to_float((inst->src[i].ud >> 16) & 0xff), brw_vf_to_float((inst->src[i].ud >> 24) & 0xff)); break; default: fprintf(file, "???"); break; } break; case ARF: switch (inst->src[i].nr) { case BRW_ARF_NULL: fprintf(file, "null"); break; case BRW_ARF_ADDRESS: fprintf(file, "a0.%d", inst->src[i].subnr); break; case BRW_ARF_ACCUMULATOR: fprintf(file, "acc%d", inst->src[i].subnr); break; case BRW_ARF_FLAG: fprintf(file, "f%d.%d", inst->src[i].nr & 0xf, inst->src[i].subnr); break; default: fprintf(file, "arf%d.%d", inst->src[i].nr & 0xf, inst->src[i].subnr); break; } break; } if (inst->src[i].offset || (inst->src[i].file == VGRF && alloc.sizes[inst->src[i].nr] * REG_SIZE != inst->size_read(i))) { const unsigned reg_size = (inst->src[i].file == UNIFORM ? 4 : REG_SIZE); fprintf(file, "+%d.%d", inst->src[i].offset / reg_size, inst->src[i].offset % reg_size); } if (inst->src[i].abs) fprintf(file, "|"); if (inst->src[i].file != IMM) { unsigned stride; if (inst->src[i].file == ARF || inst->src[i].file == FIXED_GRF) { unsigned hstride = inst->src[i].hstride; stride = (hstride == 0 ? 0 : (1 << (hstride - 1))); } else { stride = inst->src[i].stride; } if (stride != 1) fprintf(file, "<%u>", stride); fprintf(file, ":%s", brw_reg_type_to_letters(inst->src[i].type)); } if (i < inst->sources - 1 && inst->src[i + 1].file != BAD_FILE) fprintf(file, ", "); } fprintf(file, " "); if (inst->force_writemask_all) fprintf(file, "NoMask "); if (inst->exec_size != dispatch_width) fprintf(file, "group%d ", inst->group); fprintf(file, "\n"); } /** * Possibly returns an instruction that set up @param reg. * * Sometimes we want to take the result of some expression/variable * dereference tree and rewrite the instruction generating the result * of the tree. When processing the tree, we know that the * instructions generated are all writing temporaries that are dead * outside of this tree. So, if we have some instructions that write * a temporary, we're free to point that temp write somewhere else. * * Note that this doesn't guarantee that the instruction generated * only reg -- it might be the size=4 destination of a texture instruction. */ fs_inst * fs_visitor::get_instruction_generating_reg(fs_inst *start, fs_inst *end, const fs_reg ®) { if (end == start || end->is_partial_write() || !reg.equals(end->dst)) { return NULL; } else { return end; } } void fs_visitor::setup_fs_payload_gen6() { assert(stage == MESA_SHADER_FRAGMENT); struct brw_wm_prog_data *prog_data = brw_wm_prog_data(this->prog_data); assert(devinfo->gen >= 6); /* R0-1: masks, pixel X/Y coordinates. */ payload.num_regs = 2; /* R2: only for 32-pixel dispatch.*/ /* R3-26: barycentric interpolation coordinates. These appear in the * same order that they appear in the brw_barycentric_mode * enum. Each set of coordinates occupies 2 registers if dispatch width * == 8 and 4 registers if dispatch width == 16. Coordinates only * appear if they were enabled using the "Barycentric Interpolation * Mode" bits in WM_STATE. */ for (int i = 0; i < BRW_BARYCENTRIC_MODE_COUNT; ++i) { if (prog_data->barycentric_interp_modes & (1 << i)) { payload.barycentric_coord_reg[i] = payload.num_regs; payload.num_regs += 2; if (dispatch_width == 16) { payload.num_regs += 2; } } } /* R27: interpolated depth if uses source depth */ prog_data->uses_src_depth = (nir->info.inputs_read & (1 << VARYING_SLOT_POS)) != 0; if (prog_data->uses_src_depth) { payload.source_depth_reg = payload.num_regs; payload.num_regs++; if (dispatch_width == 16) { /* R28: interpolated depth if not SIMD8. */ payload.num_regs++; } } /* R29: interpolated W set if GEN6_WM_USES_SOURCE_W. */ prog_data->uses_src_w = (nir->info.inputs_read & (1 << VARYING_SLOT_POS)) != 0; if (prog_data->uses_src_w) { payload.source_w_reg = payload.num_regs; payload.num_regs++; if (dispatch_width == 16) { /* R30: interpolated W if not SIMD8. */ payload.num_regs++; } } /* R31: MSAA position offsets. */ if (prog_data->persample_dispatch && (nir->info.system_values_read & SYSTEM_BIT_SAMPLE_POS)) { /* From the Ivy Bridge PRM documentation for 3DSTATE_PS: * * "MSDISPMODE_PERSAMPLE is required in order to select * POSOFFSET_SAMPLE" * * So we can only really get sample positions if we are doing real * per-sample dispatch. If we need gl_SamplePosition and we don't have * persample dispatch, we hard-code it to 0.5. */ prog_data->uses_pos_offset = true; payload.sample_pos_reg = payload.num_regs; payload.num_regs++; } /* R32: MSAA input coverage mask */ prog_data->uses_sample_mask = (nir->info.system_values_read & SYSTEM_BIT_SAMPLE_MASK_IN) != 0; if (prog_data->uses_sample_mask) { assert(devinfo->gen >= 7); payload.sample_mask_in_reg = payload.num_regs; payload.num_regs++; if (dispatch_width == 16) { /* R33: input coverage mask if not SIMD8. */ payload.num_regs++; } } /* R34-: bary for 32-pixel. */ /* R58-59: interp W for 32-pixel. */ if (nir->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) { source_depth_to_render_target = true; } } void fs_visitor::setup_vs_payload() { /* R0: thread header, R1: urb handles */ payload.num_regs = 2; } void fs_visitor::setup_gs_payload() { assert(stage == MESA_SHADER_GEOMETRY); struct brw_gs_prog_data *gs_prog_data = brw_gs_prog_data(prog_data); struct brw_vue_prog_data *vue_prog_data = brw_vue_prog_data(prog_data); /* R0: thread header, R1: output URB handles */ payload.num_regs = 2; if (gs_prog_data->include_primitive_id) { /* R2: Primitive ID 0..7 */ payload.num_regs++; } /* Use a maximum of 24 registers for push-model inputs. */ const unsigned max_push_components = 24; /* If pushing our inputs would take too many registers, reduce the URB read * length (which is in HWords, or 8 registers), and resort to pulling. * * Note that the GS reads HWords for every vertex - so we * have to multiply by VerticesIn to obtain the total storage requirement. */ if (8 * vue_prog_data->urb_read_length * nir->info.gs.vertices_in > max_push_components || gs_prog_data->invocations > 1) { gs_prog_data->base.include_vue_handles = true; /* R3..RN: ICP Handles for each incoming vertex (when using pull model) */ payload.num_regs += nir->info.gs.vertices_in; vue_prog_data->urb_read_length = ROUND_DOWN_TO(max_push_components / nir->info.gs.vertices_in, 8) / 8; } } void fs_visitor::setup_cs_payload() { assert(devinfo->gen >= 7); payload.num_regs = 1; } void fs_visitor::calculate_register_pressure() { invalidate_live_intervals(); calculate_live_intervals(); unsigned num_instructions = 0; foreach_block(block, cfg) num_instructions += block->instructions.length(); regs_live_at_ip = rzalloc_array(mem_ctx, int, num_instructions); for (unsigned reg = 0; reg < alloc.count; reg++) { for (int ip = virtual_grf_start[reg]; ip <= virtual_grf_end[reg]; ip++) regs_live_at_ip[ip] += alloc.sizes[reg]; } } /** * Look for repeated FS_OPCODE_MOV_DISPATCH_TO_FLAGS and drop the later ones. * * The needs_unlit_centroid_workaround ends up producing one of these per * channel of centroid input, so it's good to clean them up. * * An assumption here is that nothing ever modifies the dispatched pixels * value that FS_OPCODE_MOV_DISPATCH_TO_FLAGS reads from, but the hardware * dictates that anyway. */ bool fs_visitor::opt_drop_redundant_mov_to_flags() { bool flag_mov_found[2] = {false}; bool progress = false; /* Instructions removed by this pass can only be added if this were true */ if (!devinfo->needs_unlit_centroid_workaround) return false; foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { if (inst->is_control_flow()) { memset(flag_mov_found, 0, sizeof(flag_mov_found)); } else if (inst->opcode == FS_OPCODE_MOV_DISPATCH_TO_FLAGS) { if (!flag_mov_found[inst->flag_subreg]) { flag_mov_found[inst->flag_subreg] = true; } else { inst->remove(block); progress = true; } } else if (inst->flags_written()) { flag_mov_found[inst->flag_subreg] = false; } } return progress; } void fs_visitor::optimize() { /* Start by validating the shader we currently have. */ validate(); /* bld is the common builder object pointing at the end of the program we * used to translate it into i965 IR. For the optimization and lowering * passes coming next, any code added after the end of the program without * having explicitly called fs_builder::at() clearly points at a mistake. * Ideally optimization passes wouldn't be part of the visitor so they * wouldn't have access to bld at all, but they do, so just in case some * pass forgets to ask for a location explicitly set it to NULL here to * make it trip. The dispatch width is initialized to a bogus value to * make sure that optimizations set the execution controls explicitly to * match the code they are manipulating instead of relying on the defaults. */ bld = fs_builder(this, 64); assign_constant_locations(); lower_constant_loads(); validate(); split_virtual_grfs(); validate(); #define OPT(pass, args...) ({ \ pass_num++; \ bool this_progress = pass(args); \ \ if (unlikely(INTEL_DEBUG & DEBUG_OPTIMIZER) && this_progress) { \ char filename[64]; \ snprintf(filename, 64, "%s%d-%s-%02d-%02d-" #pass, \ stage_abbrev, dispatch_width, nir->info.name, iteration, pass_num); \ \ backend_shader::dump_instructions(filename); \ } \ \ validate(); \ \ progress = progress || this_progress; \ this_progress; \ }) if (unlikely(INTEL_DEBUG & DEBUG_OPTIMIZER)) { char filename[64]; snprintf(filename, 64, "%s%d-%s-00-00-start", stage_abbrev, dispatch_width, nir->info.name); backend_shader::dump_instructions(filename); } bool progress = false; int iteration = 0; int pass_num = 0; OPT(opt_drop_redundant_mov_to_flags); do { progress = false; pass_num = 0; iteration++; OPT(remove_duplicate_mrf_writes); OPT(opt_algebraic); OPT(opt_cse); OPT(opt_copy_propagation); OPT(opt_predicated_break, this); OPT(opt_cmod_propagation); OPT(dead_code_eliminate); OPT(opt_peephole_sel); OPT(dead_control_flow_eliminate, this); OPT(opt_register_renaming); OPT(opt_saturate_propagation); OPT(register_coalesce); OPT(compute_to_mrf); OPT(eliminate_find_live_channel); OPT(compact_virtual_grfs); } while (progress); progress = false; pass_num = 0; if (OPT(lower_pack)) { OPT(register_coalesce); OPT(dead_code_eliminate); } OPT(lower_simd_width); /* After SIMD lowering just in case we had to unroll the EOT send. */ OPT(opt_sampler_eot); OPT(lower_logical_sends); if (progress) { OPT(opt_copy_propagation); /* Only run after logical send lowering because it's easier to implement * in terms of physical sends. */ if (OPT(opt_zero_samples)) OPT(opt_copy_propagation); /* Run after logical send lowering to give it a chance to CSE the * LOAD_PAYLOAD instructions created to construct the payloads of * e.g. texturing messages in cases where it wasn't possible to CSE the * whole logical instruction. */ OPT(opt_cse); OPT(register_coalesce); OPT(compute_to_mrf); OPT(dead_code_eliminate); OPT(remove_duplicate_mrf_writes); OPT(opt_peephole_sel); } OPT(opt_redundant_discard_jumps); if (OPT(lower_load_payload)) { split_virtual_grfs(); OPT(register_coalesce); OPT(compute_to_mrf); OPT(dead_code_eliminate); } OPT(opt_combine_constants); OPT(lower_integer_multiplication); if (devinfo->gen <= 5 && OPT(lower_minmax)) { OPT(opt_cmod_propagation); OPT(opt_cse); OPT(opt_copy_propagation); OPT(dead_code_eliminate); } if (OPT(lower_conversions)) { OPT(opt_copy_propagation); OPT(dead_code_eliminate); OPT(lower_simd_width); } lower_uniform_pull_constant_loads(); validate(); } /** * Three source instruction must have a GRF/MRF destination register. * ARF NULL is not allowed. Fix that up by allocating a temporary GRF. */ void fs_visitor::fixup_3src_null_dest() { bool progress = false; foreach_block_and_inst_safe (block, fs_inst, inst, cfg) { if (inst->is_3src(devinfo) && inst->dst.is_null()) { inst->dst = fs_reg(VGRF, alloc.allocate(dispatch_width / 8), inst->dst.type); progress = true; } } if (progress) invalidate_live_intervals(); } void fs_visitor::allocate_registers(bool allow_spilling) { bool allocated_without_spills; static const enum instruction_scheduler_mode pre_modes[] = { SCHEDULE_PRE, SCHEDULE_PRE_NON_LIFO, SCHEDULE_PRE_LIFO, }; bool spill_all = allow_spilling && (INTEL_DEBUG & DEBUG_SPILL_FS); /* Try each scheduling heuristic to see if it can successfully register * allocate without spilling. They should be ordered by decreasing * performance but increasing likelihood of allocating. */ for (unsigned i = 0; i < ARRAY_SIZE(pre_modes); i++) { schedule_instructions(pre_modes[i]); if (0) { assign_regs_trivial(); allocated_without_spills = true; } else { allocated_without_spills = assign_regs(false, spill_all); } if (allocated_without_spills) break; } if (!allocated_without_spills) { if (!allow_spilling) fail("Failure to register allocate and spilling is not allowed."); /* We assume that any spilling is worse than just dropping back to * SIMD8. There's probably actually some intermediate point where * SIMD16 with a couple of spills is still better. */ if (dispatch_width > min_dispatch_width) { fail("Failure to register allocate. Reduce number of " "live scalar values to avoid this."); } else { compiler->shader_perf_log(log_data, "%s shader triggered register spilling. " "Try reducing the number of live scalar " "values to improve performance.\n", stage_name); } /* Since we're out of heuristics, just go spill registers until we * get an allocation. */ while (!assign_regs(true, spill_all)) { if (failed) break; } } /* This must come after all optimization and register allocation, since * it inserts dead code that happens to have side effects, and it does * so based on the actual physical registers in use. */ insert_gen4_send_dependency_workarounds(); if (failed) return; schedule_instructions(SCHEDULE_POST); if (last_scratch > 0) { MAYBE_UNUSED unsigned max_scratch_size = 2 * 1024 * 1024; prog_data->total_scratch = brw_get_scratch_size(last_scratch); if (stage == MESA_SHADER_COMPUTE) { if (devinfo->is_haswell) { /* According to the MEDIA_VFE_STATE's "Per Thread Scratch Space" * field documentation, Haswell supports a minimum of 2kB of * scratch space for compute shaders, unlike every other stage * and platform. */ prog_data->total_scratch = MAX2(prog_data->total_scratch, 2048); } else if (devinfo->gen <= 7) { /* According to the MEDIA_VFE_STATE's "Per Thread Scratch Space" * field documentation, platforms prior to Haswell measure scratch * size linearly with a range of [1kB, 12kB] and 1kB granularity. */ prog_data->total_scratch = ALIGN(last_scratch, 1024); max_scratch_size = 12 * 1024; } } /* We currently only support up to 2MB of scratch space. If we * need to support more eventually, the documentation suggests * that we could allocate a larger buffer, and partition it out * ourselves. We'd just have to undo the hardware's address * calculation by subtracting (FFTID * Per Thread Scratch Space) * and then add FFTID * (Larger Per Thread Scratch Space). * * See 3D-Media-GPGPU Engine > Media GPGPU Pipeline > * Thread Group Tracking > Local Memory/Scratch Space. */ assert(prog_data->total_scratch < max_scratch_size); } } bool fs_visitor::run_vs(gl_clip_plane *clip_planes) { assert(stage == MESA_SHADER_VERTEX); setup_vs_payload(); if (shader_time_index >= 0) emit_shader_time_begin(); emit_nir_code(); if (failed) return false; compute_clip_distance(clip_planes); emit_urb_writes(); if (shader_time_index >= 0) emit_shader_time_end(); calculate_cfg(); optimize(); assign_curb_setup(); assign_vs_urb_setup(); fixup_3src_null_dest(); allocate_registers(true); return !failed; } bool fs_visitor::run_tcs_single_patch() { assert(stage == MESA_SHADER_TESS_CTRL); struct brw_tcs_prog_data *tcs_prog_data = brw_tcs_prog_data(prog_data); /* r1-r4 contain the ICP handles. */ payload.num_regs = 5; if (shader_time_index >= 0) emit_shader_time_begin(); /* Initialize gl_InvocationID */ fs_reg channels_uw = bld.vgrf(BRW_REGISTER_TYPE_UW); fs_reg channels_ud = bld.vgrf(BRW_REGISTER_TYPE_UD); bld.MOV(channels_uw, fs_reg(brw_imm_uv(0x76543210))); bld.MOV(channels_ud, channels_uw); if (tcs_prog_data->instances == 1) { invocation_id = channels_ud; } else { invocation_id = bld.vgrf(BRW_REGISTER_TYPE_UD); /* Get instance number from g0.2 bits 23:17, and multiply it by 8. */ fs_reg t = bld.vgrf(BRW_REGISTER_TYPE_UD); fs_reg instance_times_8 = bld.vgrf(BRW_REGISTER_TYPE_UD); bld.AND(t, fs_reg(retype(brw_vec1_grf(0, 2), BRW_REGISTER_TYPE_UD)), brw_imm_ud(INTEL_MASK(23, 17))); bld.SHR(instance_times_8, t, brw_imm_ud(17 - 3)); bld.ADD(invocation_id, instance_times_8, channels_ud); } /* Fix the disptach mask */ if (nir->info.tess.tcs_vertices_out % 8) { bld.CMP(bld.null_reg_ud(), invocation_id, brw_imm_ud(nir->info.tess.tcs_vertices_out), BRW_CONDITIONAL_L); bld.IF(BRW_PREDICATE_NORMAL); } emit_nir_code(); if (nir->info.tess.tcs_vertices_out % 8) { bld.emit(BRW_OPCODE_ENDIF); } /* Emit EOT write; set TR DS Cache bit */ fs_reg srcs[3] = { fs_reg(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_UD)), fs_reg(brw_imm_ud(WRITEMASK_X << 16)), fs_reg(brw_imm_ud(0)), }; fs_reg payload = bld.vgrf(BRW_REGISTER_TYPE_UD, 3); bld.LOAD_PAYLOAD(payload, srcs, 3, 2); fs_inst *inst = bld.emit(SHADER_OPCODE_URB_WRITE_SIMD8_MASKED, bld.null_reg_ud(), payload); inst->mlen = 3; inst->eot = true; if (shader_time_index >= 0) emit_shader_time_end(); if (failed) return false; calculate_cfg(); optimize(); assign_curb_setup(); assign_tcs_single_patch_urb_setup(); fixup_3src_null_dest(); allocate_registers(true); return !failed; } bool fs_visitor::run_tes() { assert(stage == MESA_SHADER_TESS_EVAL); /* R0: thread header, R1-3: gl_TessCoord.xyz, R4: URB handles */ payload.num_regs = 5; if (shader_time_index >= 0) emit_shader_time_begin(); emit_nir_code(); if (failed) return false; emit_urb_writes(); if (shader_time_index >= 0) emit_shader_time_end(); calculate_cfg(); optimize(); assign_curb_setup(); assign_tes_urb_setup(); fixup_3src_null_dest(); allocate_registers(true); return !failed; } bool fs_visitor::run_gs() { assert(stage == MESA_SHADER_GEOMETRY); setup_gs_payload(); this->final_gs_vertex_count = vgrf(glsl_type::uint_type); if (gs_compile->control_data_header_size_bits > 0) { /* Create a VGRF to store accumulated control data bits. */ this->control_data_bits = vgrf(glsl_type::uint_type); /* If we're outputting more than 32 control data bits, then EmitVertex() * will set control_data_bits to 0 after emitting the first vertex. * Otherwise, we need to initialize it to 0 here. */ if (gs_compile->control_data_header_size_bits <= 32) { const fs_builder abld = bld.annotate("initialize control data bits"); abld.MOV(this->control_data_bits, brw_imm_ud(0u)); } } if (shader_time_index >= 0) emit_shader_time_begin(); emit_nir_code(); emit_gs_thread_end(); if (shader_time_index >= 0) emit_shader_time_end(); if (failed) return false; calculate_cfg(); optimize(); assign_curb_setup(); assign_gs_urb_setup(); fixup_3src_null_dest(); allocate_registers(true); return !failed; } bool fs_visitor::run_fs(bool allow_spilling, bool do_rep_send) { struct brw_wm_prog_data *wm_prog_data = brw_wm_prog_data(this->prog_data); brw_wm_prog_key *wm_key = (brw_wm_prog_key *) this->key; assert(stage == MESA_SHADER_FRAGMENT); if (devinfo->gen >= 6) setup_fs_payload_gen6(); else setup_fs_payload_gen4(); if (0) { emit_dummy_fs(); } else if (do_rep_send) { assert(dispatch_width == 16); emit_repclear_shader(); } else { if (shader_time_index >= 0) emit_shader_time_begin(); calculate_urb_setup(); if (nir->info.inputs_read > 0 || (nir->info.outputs_read > 0 && !wm_key->coherent_fb_fetch)) { if (devinfo->gen < 6) emit_interpolation_setup_gen4(); else emit_interpolation_setup_gen6(); } /* We handle discards by keeping track of the still-live pixels in f0.1. * Initialize it with the dispatched pixels. */ if (wm_prog_data->uses_kill) { fs_inst *discard_init = bld.emit(FS_OPCODE_MOV_DISPATCH_TO_FLAGS); discard_init->flag_subreg = 1; } /* Generate FS IR for main(). (the visitor only descends into * functions called "main"). */ emit_nir_code(); if (failed) return false; if (wm_prog_data->uses_kill) bld.emit(FS_OPCODE_PLACEHOLDER_HALT); if (wm_key->alpha_test_func) emit_alpha_test(); emit_fb_writes(); if (shader_time_index >= 0) emit_shader_time_end(); calculate_cfg(); optimize(); assign_curb_setup(); assign_urb_setup(); fixup_3src_null_dest(); allocate_registers(allow_spilling); if (failed) return false; } return !failed; } bool fs_visitor::run_cs() { assert(stage == MESA_SHADER_COMPUTE); setup_cs_payload(); if (shader_time_index >= 0) emit_shader_time_begin(); if (devinfo->is_haswell && prog_data->total_shared > 0) { /* Move SLM index from g0.0[27:24] to sr0.1[11:8] */ const fs_builder abld = bld.exec_all().group(1, 0); abld.MOV(retype(brw_sr0_reg(1), BRW_REGISTER_TYPE_UW), suboffset(retype(brw_vec1_grf(0, 0), BRW_REGISTER_TYPE_UW), 1)); } emit_nir_code(); if (failed) return false; emit_cs_terminate(); if (shader_time_index >= 0) emit_shader_time_end(); calculate_cfg(); optimize(); assign_curb_setup(); fixup_3src_null_dest(); allocate_registers(true); if (failed) return false; return !failed; } /** * Return a bitfield where bit n is set if barycentric interpolation mode n * (see enum brw_barycentric_mode) is needed by the fragment shader. * * We examine the load_barycentric intrinsics rather than looking at input * variables so that we catch interpolateAtCentroid() messages too, which * also need the BRW_BARYCENTRIC_[NON]PERSPECTIVE_CENTROID mode set up. */ static unsigned brw_compute_barycentric_interp_modes(const struct gen_device_info *devinfo, const nir_shader *shader) { unsigned barycentric_interp_modes = 0; nir_foreach_function(f, shader) { if (!f->impl) continue; nir_foreach_block(block, f->impl) { nir_foreach_instr(instr, block) { if (instr->type != nir_instr_type_intrinsic) continue; nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); if (intrin->intrinsic != nir_intrinsic_load_interpolated_input) continue; /* Ignore WPOS; it doesn't require interpolation. */ if (nir_intrinsic_base(intrin) == VARYING_SLOT_POS) continue; intrin = nir_instr_as_intrinsic(intrin->src[0].ssa->parent_instr); enum glsl_interp_mode interp = (enum glsl_interp_mode) nir_intrinsic_interp_mode(intrin); nir_intrinsic_op bary_op = intrin->intrinsic; enum brw_barycentric_mode bary = brw_barycentric_mode(interp, bary_op); barycentric_interp_modes |= 1 << bary; if (devinfo->needs_unlit_centroid_workaround && bary_op == nir_intrinsic_load_barycentric_centroid) barycentric_interp_modes |= 1 << centroid_to_pixel(bary); } } } return barycentric_interp_modes; } static void brw_compute_flat_inputs(struct brw_wm_prog_data *prog_data, const nir_shader *shader) { prog_data->flat_inputs = 0; nir_foreach_variable(var, &shader->inputs) { int input_index = prog_data->urb_setup[var->data.location]; if (input_index < 0) continue; /* flat shading */ if (var->data.interpolation == INTERP_MODE_FLAT) prog_data->flat_inputs |= (1 << input_index); } } static uint8_t computed_depth_mode(const nir_shader *shader) { if (shader->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) { switch (shader->info.fs.depth_layout) { case FRAG_DEPTH_LAYOUT_NONE: case FRAG_DEPTH_LAYOUT_ANY: return BRW_PSCDEPTH_ON; case FRAG_DEPTH_LAYOUT_GREATER: return BRW_PSCDEPTH_ON_GE; case FRAG_DEPTH_LAYOUT_LESS: return BRW_PSCDEPTH_ON_LE; case FRAG_DEPTH_LAYOUT_UNCHANGED: return BRW_PSCDEPTH_OFF; } } return BRW_PSCDEPTH_OFF; } /** * Move load_interpolated_input with simple (payload-based) barycentric modes * to the top of the program so we don't emit multiple PLNs for the same input. * * This works around CSE not being able to handle non-dominating cases * such as: * * if (...) { * interpolate input * } else { * interpolate the same exact input * } * * This should be replaced by global value numbering someday. */ static bool move_interpolation_to_top(nir_shader *nir) { bool progress = false; nir_foreach_function(f, nir) { if (!f->impl) continue; nir_block *top = nir_start_block(f->impl); exec_node *cursor_node = NULL; nir_foreach_block(block, f->impl) { if (block == top) continue; nir_foreach_instr_safe(instr, block) { if (instr->type != nir_instr_type_intrinsic) continue; nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); if (intrin->intrinsic != nir_intrinsic_load_interpolated_input) continue; nir_intrinsic_instr *bary_intrinsic = nir_instr_as_intrinsic(intrin->src[0].ssa->parent_instr); nir_intrinsic_op op = bary_intrinsic->intrinsic; /* Leave interpolateAtSample/Offset() where they are. */ if (op == nir_intrinsic_load_barycentric_at_sample || op == nir_intrinsic_load_barycentric_at_offset) continue; nir_instr *move[3] = { &bary_intrinsic->instr, intrin->src[1].ssa->parent_instr, instr }; for (unsigned i = 0; i < ARRAY_SIZE(move); i++) { if (move[i]->block != top) { move[i]->block = top; exec_node_remove(&move[i]->node); if (cursor_node) { exec_node_insert_after(cursor_node, &move[i]->node); } else { exec_list_push_head(&top->instr_list, &move[i]->node); } cursor_node = &move[i]->node; progress = true; } } } } nir_metadata_preserve(f->impl, (nir_metadata) ((unsigned) nir_metadata_block_index | (unsigned) nir_metadata_dominance)); } return progress; } /** * Demote per-sample barycentric intrinsics to centroid. * * Useful when rendering to a non-multisampled buffer. */ static bool demote_sample_qualifiers(nir_shader *nir) { bool progress = true; nir_foreach_function(f, nir) { if (!f->impl) continue; nir_builder b; nir_builder_init(&b, f->impl); nir_foreach_block(block, f->impl) { nir_foreach_instr_safe(instr, block) { if (instr->type != nir_instr_type_intrinsic) continue; nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); if (intrin->intrinsic != nir_intrinsic_load_barycentric_sample && intrin->intrinsic != nir_intrinsic_load_barycentric_at_sample) continue; b.cursor = nir_before_instr(instr); nir_ssa_def *centroid = nir_load_barycentric(&b, nir_intrinsic_load_barycentric_centroid, nir_intrinsic_interp_mode(intrin)); nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(centroid)); nir_instr_remove(instr); progress = true; } } nir_metadata_preserve(f->impl, (nir_metadata) ((unsigned) nir_metadata_block_index | (unsigned) nir_metadata_dominance)); } return progress; } /** * Pre-gen6, the register file of the EUs was shared between threads, * and each thread used some subset allocated on a 16-register block * granularity. The unit states wanted these block counts. */ static inline int brw_register_blocks(int reg_count) { return ALIGN(reg_count, 16) / 16 - 1; } const unsigned * brw_compile_fs(const struct brw_compiler *compiler, void *log_data, void *mem_ctx, const struct brw_wm_prog_key *key, struct brw_wm_prog_data *prog_data, const nir_shader *src_shader, struct gl_program *prog, int shader_time_index8, int shader_time_index16, bool allow_spilling, bool use_rep_send, struct brw_vue_map *vue_map, unsigned *final_assembly_size, char **error_str) { const struct gen_device_info *devinfo = compiler->devinfo; nir_shader *shader = nir_shader_clone(mem_ctx, src_shader); shader = brw_nir_apply_sampler_key(shader, compiler, &key->tex, true); brw_nir_lower_fs_inputs(shader, devinfo, key); brw_nir_lower_fs_outputs(shader); if (devinfo->gen < 6) { brw_setup_vue_interpolation(vue_map, shader, prog_data, devinfo); } if (!key->multisample_fbo) NIR_PASS_V(shader, demote_sample_qualifiers); NIR_PASS_V(shader, move_interpolation_to_top); shader = brw_postprocess_nir(shader, compiler, true); /* key->alpha_test_func means simulating alpha testing via discards, * so the shader definitely kills pixels. */ prog_data->uses_kill = shader->info.fs.uses_discard || key->alpha_test_func; prog_data->uses_omask = key->multisample_fbo && shader->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_SAMPLE_MASK); prog_data->computed_depth_mode = computed_depth_mode(shader); prog_data->computed_stencil = shader->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_STENCIL); prog_data->persample_dispatch = key->multisample_fbo && (key->persample_interp || (shader->info.system_values_read & (SYSTEM_BIT_SAMPLE_ID | SYSTEM_BIT_SAMPLE_POS)) || shader->info.fs.uses_sample_qualifier || shader->info.outputs_read); prog_data->has_render_target_reads = shader->info.outputs_read != 0ull; prog_data->early_fragment_tests = shader->info.fs.early_fragment_tests; prog_data->post_depth_coverage = shader->info.fs.post_depth_coverage; prog_data->inner_coverage = shader->info.fs.inner_coverage; prog_data->barycentric_interp_modes = brw_compute_barycentric_interp_modes(compiler->devinfo, shader); cfg_t *simd8_cfg = NULL, *simd16_cfg = NULL; uint8_t simd8_grf_start = 0, simd16_grf_start = 0; unsigned simd8_grf_used = 0, simd16_grf_used = 0; fs_visitor v8(compiler, log_data, mem_ctx, key, &prog_data->base, prog, shader, 8, shader_time_index8); if (!v8.run_fs(allow_spilling, false /* do_rep_send */)) { if (error_str) *error_str = ralloc_strdup(mem_ctx, v8.fail_msg); return NULL; } else if (likely(!(INTEL_DEBUG & DEBUG_NO8))) { simd8_cfg = v8.cfg; simd8_grf_start = v8.payload.num_regs; simd8_grf_used = v8.grf_used; } if (v8.max_dispatch_width >= 16 && likely(!(INTEL_DEBUG & DEBUG_NO16) || use_rep_send)) { /* Try a SIMD16 compile */ fs_visitor v16(compiler, log_data, mem_ctx, key, &prog_data->base, prog, shader, 16, shader_time_index16); v16.import_uniforms(&v8); if (!v16.run_fs(allow_spilling, use_rep_send)) { compiler->shader_perf_log(log_data, "SIMD16 shader failed to compile: %s", v16.fail_msg); } else { simd16_cfg = v16.cfg; simd16_grf_start = v16.payload.num_regs; simd16_grf_used = v16.grf_used; } } /* When the caller requests a repclear shader, they want SIMD16-only */ if (use_rep_send) simd8_cfg = NULL; /* Prior to Iron Lake, the PS had a single shader offset with a jump table * at the top to select the shader. We've never implemented that. * Instead, we just give them exactly one shader and we pick the widest one * available. */ if (compiler->devinfo->gen < 5 && simd16_cfg) simd8_cfg = NULL; if (prog_data->persample_dispatch) { /* Starting with SandyBridge (where we first get MSAA), the different * pixel dispatch combinations are grouped into classifications A * through F (SNB PRM Vol. 2 Part 1 Section 7.7.1). On all hardware * generations, the only configurations supporting persample dispatch * are are this in which only one dispatch width is enabled. * * If computed depth is enabled, SNB only allows SIMD8 while IVB+ * allow SIMD8 or SIMD16 so we choose SIMD16 if available. */ if (compiler->devinfo->gen == 6 && prog_data->computed_depth_mode != BRW_PSCDEPTH_OFF) { simd16_cfg = NULL; } else if (simd16_cfg) { simd8_cfg = NULL; } } /* We have to compute the flat inputs after the visitor is finished running * because it relies on prog_data->urb_setup which is computed in * fs_visitor::calculate_urb_setup(). */ brw_compute_flat_inputs(prog_data, shader); fs_generator g(compiler, log_data, mem_ctx, (void *) key, &prog_data->base, v8.promoted_constants, v8.runtime_check_aads_emit, MESA_SHADER_FRAGMENT); if (unlikely(INTEL_DEBUG & DEBUG_WM)) { g.enable_debug(ralloc_asprintf(mem_ctx, "%s fragment shader %s", shader->info.label ? shader->info.label : "unnamed", shader->info.name)); } if (simd8_cfg) { prog_data->dispatch_8 = true; g.generate_code(simd8_cfg, 8); prog_data->base.dispatch_grf_start_reg = simd8_grf_start; prog_data->reg_blocks_0 = brw_register_blocks(simd8_grf_used); if (simd16_cfg) { prog_data->dispatch_16 = true; prog_data->prog_offset_2 = g.generate_code(simd16_cfg, 16); prog_data->dispatch_grf_start_reg_2 = simd16_grf_start; prog_data->reg_blocks_2 = brw_register_blocks(simd16_grf_used); } } else if (simd16_cfg) { prog_data->dispatch_16 = true; g.generate_code(simd16_cfg, 16); prog_data->base.dispatch_grf_start_reg = simd16_grf_start; prog_data->reg_blocks_0 = brw_register_blocks(simd16_grf_used); } return g.get_assembly(final_assembly_size); } fs_reg * fs_visitor::emit_cs_work_group_id_setup() { assert(stage == MESA_SHADER_COMPUTE); fs_reg *reg = new(this->mem_ctx) fs_reg(vgrf(glsl_type::uvec3_type)); struct brw_reg r0_1(retype(brw_vec1_grf(0, 1), BRW_REGISTER_TYPE_UD)); struct brw_reg r0_6(retype(brw_vec1_grf(0, 6), BRW_REGISTER_TYPE_UD)); struct brw_reg r0_7(retype(brw_vec1_grf(0, 7), BRW_REGISTER_TYPE_UD)); bld.MOV(*reg, r0_1); bld.MOV(offset(*reg, bld, 1), r0_6); bld.MOV(offset(*reg, bld, 2), r0_7); return reg; } static void fill_push_const_block_info(struct brw_push_const_block *block, unsigned dwords) { block->dwords = dwords; block->regs = DIV_ROUND_UP(dwords, 8); block->size = block->regs * 32; } static void cs_fill_push_const_info(const struct gen_device_info *devinfo, struct brw_cs_prog_data *cs_prog_data) { const struct brw_stage_prog_data *prog_data = &cs_prog_data->base; bool fill_thread_id = cs_prog_data->thread_local_id_index >= 0 && cs_prog_data->thread_local_id_index < (int)prog_data->nr_params; bool cross_thread_supported = devinfo->gen > 7 || devinfo->is_haswell; /* The thread ID should be stored in the last param dword */ assert(prog_data->nr_params > 0 || !fill_thread_id); assert(!fill_thread_id || cs_prog_data->thread_local_id_index == (int)prog_data->nr_params - 1); unsigned cross_thread_dwords, per_thread_dwords; if (!cross_thread_supported) { cross_thread_dwords = 0u; per_thread_dwords = prog_data->nr_params; } else if (fill_thread_id) { /* Fill all but the last register with cross-thread payload */ cross_thread_dwords = 8 * (cs_prog_data->thread_local_id_index / 8); per_thread_dwords = prog_data->nr_params - cross_thread_dwords; assert(per_thread_dwords > 0 && per_thread_dwords <= 8); } else { /* Fill all data using cross-thread payload */ cross_thread_dwords = prog_data->nr_params; per_thread_dwords = 0u; } fill_push_const_block_info(&cs_prog_data->push.cross_thread, cross_thread_dwords); fill_push_const_block_info(&cs_prog_data->push.per_thread, per_thread_dwords); unsigned total_dwords = (cs_prog_data->push.per_thread.size * cs_prog_data->threads + cs_prog_data->push.cross_thread.size) / 4; fill_push_const_block_info(&cs_prog_data->push.total, total_dwords); assert(cs_prog_data->push.cross_thread.dwords % 8 == 0 || cs_prog_data->push.per_thread.size == 0); assert(cs_prog_data->push.cross_thread.dwords + cs_prog_data->push.per_thread.dwords == prog_data->nr_params); } static void cs_set_simd_size(struct brw_cs_prog_data *cs_prog_data, unsigned size) { cs_prog_data->simd_size = size; unsigned group_size = cs_prog_data->local_size[0] * cs_prog_data->local_size[1] * cs_prog_data->local_size[2]; cs_prog_data->threads = (group_size + size - 1) / size; } const unsigned * brw_compile_cs(const struct brw_compiler *compiler, void *log_data, void *mem_ctx, const struct brw_cs_prog_key *key, struct brw_cs_prog_data *prog_data, const nir_shader *src_shader, int shader_time_index, unsigned *final_assembly_size, char **error_str) { nir_shader *shader = nir_shader_clone(mem_ctx, src_shader); shader = brw_nir_apply_sampler_key(shader, compiler, &key->tex, true); /* Now that we cloned the nir_shader, we can update num_uniforms based on * the thread_local_id_index. */ assert(prog_data->thread_local_id_index >= 0); shader->num_uniforms = MAX2(shader->num_uniforms, (unsigned)4 * (prog_data->thread_local_id_index + 1)); brw_nir_lower_intrinsics(shader, &prog_data->base); shader = brw_postprocess_nir(shader, compiler, true); prog_data->local_size[0] = shader->info.cs.local_size[0]; prog_data->local_size[1] = shader->info.cs.local_size[1]; prog_data->local_size[2] = shader->info.cs.local_size[2]; unsigned local_workgroup_size = shader->info.cs.local_size[0] * shader->info.cs.local_size[1] * shader->info.cs.local_size[2]; unsigned max_cs_threads = compiler->devinfo->max_cs_threads; unsigned simd_required = DIV_ROUND_UP(local_workgroup_size, max_cs_threads); cfg_t *cfg = NULL; const char *fail_msg = NULL; /* Now the main event: Visit the shader IR and generate our CS IR for it. */ fs_visitor v8(compiler, log_data, mem_ctx, key, &prog_data->base, NULL, /* Never used in core profile */ shader, 8, shader_time_index); if (simd_required <= 8) { if (!v8.run_cs()) { fail_msg = v8.fail_msg; } else { cfg = v8.cfg; cs_set_simd_size(prog_data, 8); cs_fill_push_const_info(compiler->devinfo, prog_data); prog_data->base.dispatch_grf_start_reg = v8.payload.num_regs; } } fs_visitor v16(compiler, log_data, mem_ctx, key, &prog_data->base, NULL, /* Never used in core profile */ shader, 16, shader_time_index); if (likely(!(INTEL_DEBUG & DEBUG_NO16)) && !fail_msg && v8.max_dispatch_width >= 16 && simd_required <= 16) { /* Try a SIMD16 compile */ if (simd_required <= 8) v16.import_uniforms(&v8); if (!v16.run_cs()) { compiler->shader_perf_log(log_data, "SIMD16 shader failed to compile: %s", v16.fail_msg); if (!cfg) { fail_msg = "Couldn't generate SIMD16 program and not " "enough threads for SIMD8"; } } else { cfg = v16.cfg; cs_set_simd_size(prog_data, 16); cs_fill_push_const_info(compiler->devinfo, prog_data); prog_data->dispatch_grf_start_reg_16 = v16.payload.num_regs; } } fs_visitor v32(compiler, log_data, mem_ctx, key, &prog_data->base, NULL, /* Never used in core profile */ shader, 32, shader_time_index); if (!fail_msg && v8.max_dispatch_width >= 32 && (simd_required > 16 || (INTEL_DEBUG & DEBUG_DO32))) { /* Try a SIMD32 compile */ if (simd_required <= 8) v32.import_uniforms(&v8); else if (simd_required <= 16) v32.import_uniforms(&v16); if (!v32.run_cs()) { compiler->shader_perf_log(log_data, "SIMD32 shader failed to compile: %s", v16.fail_msg); if (!cfg) { fail_msg = "Couldn't generate SIMD32 program and not " "enough threads for SIMD16"; } } else { cfg = v32.cfg; cs_set_simd_size(prog_data, 32); cs_fill_push_const_info(compiler->devinfo, prog_data); } } if (unlikely(cfg == NULL)) { assert(fail_msg); if (error_str) *error_str = ralloc_strdup(mem_ctx, fail_msg); return NULL; } fs_generator g(compiler, log_data, mem_ctx, (void*) key, &prog_data->base, v8.promoted_constants, v8.runtime_check_aads_emit, MESA_SHADER_COMPUTE); if (INTEL_DEBUG & DEBUG_CS) { char *name = ralloc_asprintf(mem_ctx, "%s compute shader %s", shader->info.label ? shader->info.label : "unnamed", shader->info.name); g.enable_debug(name); } g.generate_code(cfg, prog_data->simd_size); return g.get_assembly(final_assembly_size); } /** * Test the dispatch mask packing assumptions of * brw_stage_has_packed_dispatch(). Call this from e.g. the top of * fs_visitor::emit_nir_code() to cause a GPU hang if any shader invocation is * executed with an unexpected dispatch mask. */ static UNUSED void brw_fs_test_dispatch_packing(const fs_builder &bld) { const gl_shader_stage stage = bld.shader->stage; if (brw_stage_has_packed_dispatch(bld.shader->devinfo, stage, bld.shader->stage_prog_data)) { const fs_builder ubld = bld.exec_all().group(1, 0); const fs_reg tmp = component(bld.vgrf(BRW_REGISTER_TYPE_UD), 0); const fs_reg mask = (stage == MESA_SHADER_FRAGMENT ? brw_vmask_reg() : brw_dmask_reg()); ubld.ADD(tmp, mask, brw_imm_ud(1)); ubld.AND(tmp, mask, tmp); /* This will loop forever if the dispatch mask doesn't have the expected * form '2^n-1', in which case tmp will be non-zero. */ bld.emit(BRW_OPCODE_DO); bld.CMP(bld.null_reg_ud(), tmp, brw_imm_ud(0), BRW_CONDITIONAL_NZ); set_predicate(BRW_PREDICATE_NORMAL, bld.emit(BRW_OPCODE_WHILE)); } }