/* * Copyright © 2010 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. */ /** @file brw_fs_visitor.cpp * * This file supports generating the FS LIR from the GLSL IR. The LIR * makes it easier to do backend-specific optimizations than doing so * in the GLSL IR or in the native code. */ #include #include "main/macros.h" #include "main/shaderobj.h" #include "program/prog_parameter.h" #include "program/prog_print.h" #include "program/prog_optimize.h" #include "util/register_allocate.h" #include "program/hash_table.h" #include "brw_context.h" #include "brw_eu.h" #include "brw_wm.h" #include "brw_cs.h" #include "brw_vec4.h" #include "brw_fs.h" #include "main/uniforms.h" #include "glsl/glsl_types.h" #include "glsl/ir_optimization.h" #include "program/sampler.h" using namespace brw; fs_reg * fs_visitor::emit_vs_system_value(int location) { fs_reg *reg = new(this->mem_ctx) fs_reg(ATTR, VERT_ATTRIB_MAX, BRW_REGISTER_TYPE_D); brw_vs_prog_data *vs_prog_data = (brw_vs_prog_data *) prog_data; switch (location) { case SYSTEM_VALUE_BASE_VERTEX: reg->reg_offset = 0; vs_prog_data->uses_vertexid = true; break; case SYSTEM_VALUE_VERTEX_ID: case SYSTEM_VALUE_VERTEX_ID_ZERO_BASE: reg->reg_offset = 2; vs_prog_data->uses_vertexid = true; break; case SYSTEM_VALUE_INSTANCE_ID: reg->reg_offset = 3; vs_prog_data->uses_instanceid = true; break; default: unreachable("not reached"); } return reg; } fs_reg fs_visitor::rescale_texcoord(fs_reg coordinate, int coord_components, bool is_rect, uint32_t sampler, int texunit) { bool needs_gl_clamp = true; fs_reg scale_x, scale_y; /* The 965 requires the EU to do the normalization of GL rectangle * texture coordinates. We use the program parameter state * tracking to get the scaling factor. */ if (is_rect && (devinfo->gen < 6 || (devinfo->gen >= 6 && (key_tex->gl_clamp_mask[0] & (1 << sampler) || key_tex->gl_clamp_mask[1] & (1 << sampler))))) { struct gl_program_parameter_list *params = prog->Parameters; int tokens[STATE_LENGTH] = { STATE_INTERNAL, STATE_TEXRECT_SCALE, texunit, 0, 0 }; no16("rectangle scale uniform setup not supported on SIMD16\n"); if (dispatch_width == 16) { return coordinate; } GLuint index = _mesa_add_state_reference(params, (gl_state_index *)tokens); /* Try to find existing copies of the texrect scale uniforms. */ for (unsigned i = 0; i < uniforms; i++) { if (stage_prog_data->param[i] == &prog->Parameters->ParameterValues[index][0]) { scale_x = fs_reg(UNIFORM, i); scale_y = fs_reg(UNIFORM, i + 1); break; } } /* If we didn't already set them up, do so now. */ if (scale_x.file == BAD_FILE) { scale_x = fs_reg(UNIFORM, uniforms); scale_y = fs_reg(UNIFORM, uniforms + 1); stage_prog_data->param[uniforms++] = &prog->Parameters->ParameterValues[index][0]; stage_prog_data->param[uniforms++] = &prog->Parameters->ParameterValues[index][1]; } } /* The 965 requires the EU to do the normalization of GL rectangle * texture coordinates. We use the program parameter state * tracking to get the scaling factor. */ if (devinfo->gen < 6 && is_rect) { fs_reg dst = fs_reg(GRF, alloc.allocate(coord_components)); fs_reg src = coordinate; coordinate = dst; bld.MUL(dst, src, scale_x); dst = offset(dst, bld, 1); src = offset(src, bld, 1); bld.MUL(dst, src, scale_y); } else if (is_rect) { /* On gen6+, the sampler handles the rectangle coordinates * natively, without needing rescaling. But that means we have * to do GL_CLAMP clamping at the [0, width], [0, height] scale, * not [0, 1] like the default case below. */ needs_gl_clamp = false; for (int i = 0; i < 2; i++) { if (key_tex->gl_clamp_mask[i] & (1 << sampler)) { fs_reg chan = coordinate; chan = offset(chan, bld, i); set_condmod(BRW_CONDITIONAL_GE, bld.emit(BRW_OPCODE_SEL, chan, chan, fs_reg(0.0f))); /* Our parameter comes in as 1.0/width or 1.0/height, * because that's what people normally want for doing * texture rectangle handling. We need width or height * for clamping, but we don't care enough to make a new * parameter type, so just invert back. */ fs_reg limit = vgrf(glsl_type::float_type); bld.MOV(limit, i == 0 ? scale_x : scale_y); bld.emit(SHADER_OPCODE_RCP, limit, limit); set_condmod(BRW_CONDITIONAL_L, bld.emit(BRW_OPCODE_SEL, chan, chan, limit)); } } } if (coord_components > 0 && needs_gl_clamp) { for (int i = 0; i < MIN2(coord_components, 3); i++) { if (key_tex->gl_clamp_mask[i] & (1 << sampler)) { fs_reg chan = coordinate; chan = offset(chan, bld, i); set_saturate(true, bld.MOV(chan, chan)); } } } return coordinate; } /* Sample from the MCS surface attached to this multisample texture. */ fs_reg fs_visitor::emit_mcs_fetch(const fs_reg &coordinate, unsigned components, const fs_reg &sampler) { const fs_reg dest = vgrf(glsl_type::uvec4_type); const fs_reg srcs[] = { coordinate, fs_reg(), fs_reg(), fs_reg(), fs_reg(), fs_reg(), sampler, fs_reg(), fs_reg(components), fs_reg(0) }; fs_inst *inst = bld.emit(SHADER_OPCODE_TXF_MCS_LOGICAL, dest, srcs, ARRAY_SIZE(srcs)); /* We only care about one reg of response, but the sampler always writes * 4/8. */ inst->regs_written = 4 * dispatch_width / 8; return dest; } void fs_visitor::emit_texture(ir_texture_opcode op, const glsl_type *dest_type, fs_reg coordinate, int coord_components, fs_reg shadow_c, fs_reg lod, fs_reg lod2, int grad_components, fs_reg sample_index, fs_reg offset_value, fs_reg mcs, int gather_component, bool is_cube_array, bool is_rect, uint32_t sampler, fs_reg sampler_reg, int texunit) { fs_inst *inst = NULL; if (op == ir_tg4) { /* When tg4 is used with the degenerate ZERO/ONE swizzles, don't bother * emitting anything other than setting up the constant result. */ int swiz = GET_SWZ(key_tex->swizzles[sampler], gather_component); if (swiz == SWIZZLE_ZERO || swiz == SWIZZLE_ONE) { fs_reg res = vgrf(glsl_type::vec4_type); this->result = res; for (int i=0; i<4; i++) { bld.MOV(res, fs_reg(swiz == SWIZZLE_ZERO ? 0.0f : 1.0f)); res = offset(res, bld, 1); } return; } } if (op == ir_query_levels) { /* textureQueryLevels() is implemented in terms of TXS so we need to * pass a valid LOD argument. */ assert(lod.file == BAD_FILE); lod = fs_reg(0u); } if (coordinate.file != BAD_FILE) { /* FINISHME: Texture coordinate rescaling doesn't work with non-constant * samplers. This should only be a problem with GL_CLAMP on Gen7. */ coordinate = rescale_texcoord(coordinate, coord_components, is_rect, sampler, texunit); } /* Writemasking doesn't eliminate channels on SIMD8 texture * samples, so don't worry about them. */ fs_reg dst = vgrf(glsl_type::get_instance(dest_type->base_type, 4, 1)); const fs_reg srcs[] = { coordinate, shadow_c, lod, lod2, sample_index, mcs, sampler_reg, offset_value, fs_reg(coord_components), fs_reg(grad_components) }; enum opcode opcode; switch (op) { case ir_tex: opcode = SHADER_OPCODE_TEX_LOGICAL; break; case ir_txb: opcode = FS_OPCODE_TXB_LOGICAL; break; case ir_txl: opcode = SHADER_OPCODE_TXL_LOGICAL; break; case ir_txd: opcode = SHADER_OPCODE_TXD_LOGICAL; break; case ir_txf: opcode = SHADER_OPCODE_TXF_LOGICAL; break; case ir_txf_ms: opcode = SHADER_OPCODE_TXF_CMS_LOGICAL; break; case ir_txs: case ir_query_levels: opcode = SHADER_OPCODE_TXS_LOGICAL; break; case ir_lod: opcode = SHADER_OPCODE_LOD_LOGICAL; break; case ir_tg4: opcode = (offset_value.file != BAD_FILE && offset_value.file != IMM ? SHADER_OPCODE_TG4_OFFSET_LOGICAL : SHADER_OPCODE_TG4_LOGICAL); break; default: unreachable("Invalid texture opcode."); } inst = bld.emit(opcode, dst, srcs, ARRAY_SIZE(srcs)); inst->regs_written = 4 * dispatch_width / 8; if (shadow_c.file != BAD_FILE) inst->shadow_compare = true; if (offset_value.file == IMM) inst->offset = offset_value.fixed_hw_reg.dw1.ud; if (op == ir_tg4) { inst->offset |= gather_channel(gather_component, sampler) << 16; /* M0.2:16-17 */ if (devinfo->gen == 6) emit_gen6_gather_wa(key_tex->gen6_gather_wa[sampler], dst); } /* fixup #layers for cube map arrays */ if (op == ir_txs && is_cube_array) { fs_reg depth = offset(dst, bld, 2); fs_reg fixed_depth = vgrf(glsl_type::int_type); bld.emit(SHADER_OPCODE_INT_QUOTIENT, fixed_depth, depth, fs_reg(6)); fs_reg *fixed_payload = ralloc_array(mem_ctx, fs_reg, inst->regs_written); int components = inst->regs_written / (inst->exec_size / 8); for (int i = 0; i < components; i++) { if (i == 2) { fixed_payload[i] = fixed_depth; } else { fixed_payload[i] = offset(dst, bld, i); } } bld.LOAD_PAYLOAD(dst, fixed_payload, components, 0); } swizzle_result(op, dest_type->vector_elements, dst, sampler); } /** * Apply workarounds for Gen6 gather with UINT/SINT */ void fs_visitor::emit_gen6_gather_wa(uint8_t wa, fs_reg dst) { if (!wa) return; int width = (wa & WA_8BIT) ? 8 : 16; for (int i = 0; i < 4; i++) { fs_reg dst_f = retype(dst, BRW_REGISTER_TYPE_F); /* Convert from UNORM to UINT */ bld.MUL(dst_f, dst_f, fs_reg((float)((1 << width) - 1))); bld.MOV(dst, dst_f); if (wa & WA_SIGN) { /* Reinterpret the UINT value as a signed INT value by * shifting the sign bit into place, then shifting back * preserving sign. */ bld.SHL(dst, dst, fs_reg(32 - width)); bld.ASR(dst, dst, fs_reg(32 - width)); } dst = offset(dst, bld, 1); } } /** * Set up the gather channel based on the swizzle, for gather4. */ uint32_t fs_visitor::gather_channel(int orig_chan, uint32_t sampler) { int swiz = GET_SWZ(key_tex->swizzles[sampler], orig_chan); switch (swiz) { case SWIZZLE_X: return 0; case SWIZZLE_Y: /* gather4 sampler is broken for green channel on RG32F -- * we must ask for blue instead. */ if (key_tex->gather_channel_quirk_mask & (1 << sampler)) return 2; return 1; case SWIZZLE_Z: return 2; case SWIZZLE_W: return 3; default: unreachable("Not reached"); /* zero, one swizzles handled already */ } } /** * Swizzle the result of a texture result. This is necessary for * EXT_texture_swizzle as well as DEPTH_TEXTURE_MODE for shadow comparisons. */ void fs_visitor::swizzle_result(ir_texture_opcode op, int dest_components, fs_reg orig_val, uint32_t sampler) { if (op == ir_query_levels) { /* # levels is in .w */ this->result = offset(orig_val, bld, 3); return; } this->result = orig_val; /* txs,lod don't actually sample the texture, so swizzling the result * makes no sense. */ if (op == ir_txs || op == ir_lod || op == ir_tg4) return; if (dest_components == 1) { /* Ignore DEPTH_TEXTURE_MODE swizzling. */ } else if (key_tex->swizzles[sampler] != SWIZZLE_NOOP) { fs_reg swizzled_result = vgrf(glsl_type::vec4_type); swizzled_result.type = orig_val.type; for (int i = 0; i < 4; i++) { int swiz = GET_SWZ(key_tex->swizzles[sampler], i); fs_reg l = swizzled_result; l = offset(l, bld, i); if (swiz == SWIZZLE_ZERO) { bld.MOV(l, fs_reg(0.0f)); } else if (swiz == SWIZZLE_ONE) { bld.MOV(l, fs_reg(1.0f)); } else { bld.MOV(l, offset(orig_val, bld, GET_SWZ(key_tex->swizzles[sampler], i))); } } this->result = swizzled_result; } } /** * Try to replace IF/MOV/ELSE/MOV/ENDIF with SEL. * * Many GLSL shaders contain the following pattern: * * x = condition ? foo : bar * * The compiler emits an ir_if tree for this, since each subexpression might be * a complex tree that could have side-effects or short-circuit logic. * * However, the common case is to simply select one of two constants or * variable values---which is exactly what SEL is for. In this case, the * assembly looks like: * * (+f0) IF * MOV dst src0 * ELSE * MOV dst src1 * ENDIF * * which can be easily translated into: * * (+f0) SEL dst src0 src1 * * If src0 is an immediate value, we promote it to a temporary GRF. */ bool fs_visitor::try_replace_with_sel() { fs_inst *endif_inst = (fs_inst *) instructions.get_tail(); assert(endif_inst->opcode == BRW_OPCODE_ENDIF); /* Pattern match in reverse: IF, MOV, ELSE, MOV, ENDIF. */ int opcodes[] = { BRW_OPCODE_IF, BRW_OPCODE_MOV, BRW_OPCODE_ELSE, BRW_OPCODE_MOV, }; fs_inst *match = (fs_inst *) endif_inst->prev; for (int i = 0; i < 4; i++) { if (match->is_head_sentinel() || match->opcode != opcodes[4-i-1]) return false; match = (fs_inst *) match->prev; } /* The opcodes match; it looks like the right sequence of instructions. */ fs_inst *else_mov = (fs_inst *) endif_inst->prev; fs_inst *then_mov = (fs_inst *) else_mov->prev->prev; fs_inst *if_inst = (fs_inst *) then_mov->prev; /* Check that the MOVs are the right form. */ if (then_mov->dst.equals(else_mov->dst) && !then_mov->is_partial_write() && !else_mov->is_partial_write()) { /* Remove the matched instructions; we'll emit a SEL to replace them. */ while (!if_inst->next->is_tail_sentinel()) if_inst->next->exec_node::remove(); if_inst->exec_node::remove(); /* Only the last source register can be a constant, so if the MOV in * the "then" clause uses a constant, we need to put it in a temporary. */ fs_reg src0(then_mov->src[0]); if (src0.file == IMM) { src0 = vgrf(glsl_type::float_type); src0.type = then_mov->src[0].type; bld.MOV(src0, then_mov->src[0]); } if (if_inst->conditional_mod) { /* Sandybridge-specific IF with embedded comparison */ bld.CMP(bld.null_reg_d(), if_inst->src[0], if_inst->src[1], if_inst->conditional_mod); set_predicate(BRW_PREDICATE_NORMAL, bld.emit(BRW_OPCODE_SEL, then_mov->dst, src0, else_mov->src[0])); } else { /* Separate CMP and IF instructions */ set_predicate_inv(if_inst->predicate, if_inst->predicate_inverse, bld.emit(BRW_OPCODE_SEL, then_mov->dst, src0, else_mov->src[0])); } return true; } return false; } void fs_visitor::emit_untyped_atomic(unsigned atomic_op, unsigned surf_index, fs_reg dst, fs_reg offset, fs_reg src0, fs_reg src1) { int reg_width = dispatch_width / 8; int length = 0; fs_reg *sources = ralloc_array(mem_ctx, fs_reg, 4); sources[0] = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* Initialize the sample mask in the message header. */ bld.exec_all().MOV(sources[0], fs_reg(0u)); if (stage == MESA_SHADER_FRAGMENT) { if (((brw_wm_prog_data*)this->prog_data)->uses_kill) { bld.exec_all() .MOV(component(sources[0], 7), brw_flag_reg(0, 1)); } else { bld.exec_all() .MOV(component(sources[0], 7), retype(brw_vec1_grf(1, 7), BRW_REGISTER_TYPE_UD)); } } else { /* The execution mask is part of the side-band information sent together with * the message payload to the data port. It's implicitly ANDed with the sample * mask sent in the header to compute the actual set of channels that execute * the atomic operation. */ assert(stage == MESA_SHADER_VERTEX || stage == MESA_SHADER_COMPUTE); bld.exec_all() .MOV(component(sources[0], 7), fs_reg(0xffffu)); } length++; /* Set the atomic operation offset. */ sources[1] = vgrf(glsl_type::uint_type); bld.MOV(sources[1], offset); length++; /* Set the atomic operation arguments. */ if (src0.file != BAD_FILE) { sources[length] = vgrf(glsl_type::uint_type); bld.MOV(sources[length], src0); length++; } if (src1.file != BAD_FILE) { sources[length] = vgrf(glsl_type::uint_type); bld.MOV(sources[length], src1); length++; } int mlen = 1 + (length - 1) * reg_width; fs_reg src_payload = fs_reg(GRF, alloc.allocate(mlen), BRW_REGISTER_TYPE_UD); bld.LOAD_PAYLOAD(src_payload, sources, length, 1); /* Emit the instruction. */ fs_inst *inst = bld.emit(SHADER_OPCODE_UNTYPED_ATOMIC, dst, src_payload, fs_reg(surf_index), fs_reg(atomic_op)); inst->mlen = mlen; } void fs_visitor::emit_untyped_surface_read(unsigned surf_index, fs_reg dst, fs_reg offset) { int reg_width = dispatch_width / 8; fs_reg *sources = ralloc_array(mem_ctx, fs_reg, 2); sources[0] = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* Initialize the sample mask in the message header. */ bld.exec_all() .MOV(sources[0], fs_reg(0u)); if (stage == MESA_SHADER_FRAGMENT) { if (((brw_wm_prog_data*)this->prog_data)->uses_kill) { bld.exec_all() .MOV(component(sources[0], 7), brw_flag_reg(0, 1)); } else { bld.exec_all() .MOV(component(sources[0], 7), retype(brw_vec1_grf(1, 7), BRW_REGISTER_TYPE_UD)); } } else { /* The execution mask is part of the side-band information sent together with * the message payload to the data port. It's implicitly ANDed with the sample * mask sent in the header to compute the actual set of channels that execute * the atomic operation. */ assert(stage == MESA_SHADER_VERTEX || stage == MESA_SHADER_COMPUTE); bld.exec_all() .MOV(component(sources[0], 7), fs_reg(0xffffu)); } /* Set the surface read offset. */ sources[1] = vgrf(glsl_type::uint_type); bld.MOV(sources[1], offset); int mlen = 1 + reg_width; fs_reg src_payload = fs_reg(GRF, alloc.allocate(mlen), BRW_REGISTER_TYPE_UD); fs_inst *inst = bld.LOAD_PAYLOAD(src_payload, sources, 2, 1); /* Emit the instruction. */ inst = bld.emit(SHADER_OPCODE_UNTYPED_SURFACE_READ, dst, src_payload, fs_reg(surf_index), fs_reg(1)); inst->mlen = mlen; } /** Emits a dummy fragment shader consisting of magenta for bringup purposes. */ void fs_visitor::emit_dummy_fs() { int reg_width = dispatch_width / 8; /* Everyone's favorite color. */ const float color[4] = { 1.0, 0.0, 1.0, 0.0 }; for (int i = 0; i < 4; i++) { bld.MOV(fs_reg(MRF, 2 + i * reg_width, BRW_REGISTER_TYPE_F), fs_reg(color[i])); } fs_inst *write; write = bld.emit(FS_OPCODE_FB_WRITE); write->eot = true; if (devinfo->gen >= 6) { write->base_mrf = 2; write->mlen = 4 * reg_width; } else { write->header_size = 2; write->base_mrf = 0; write->mlen = 2 + 4 * reg_width; } /* Tell the SF we don't have any inputs. Gen4-5 require at least one * varying to avoid GPU hangs, so set that. */ brw_wm_prog_data *wm_prog_data = (brw_wm_prog_data *) this->prog_data; wm_prog_data->num_varying_inputs = devinfo->gen < 6 ? 1 : 0; memset(wm_prog_data->urb_setup, -1, sizeof(wm_prog_data->urb_setup[0]) * VARYING_SLOT_MAX); /* We don't have any uniforms. */ stage_prog_data->nr_params = 0; stage_prog_data->nr_pull_params = 0; stage_prog_data->curb_read_length = 0; stage_prog_data->dispatch_grf_start_reg = 2; wm_prog_data->dispatch_grf_start_reg_16 = 2; grf_used = 1; /* Gen4-5 don't allow zero GRF blocks */ calculate_cfg(); } /* The register location here is relative to the start of the URB * data. It will get adjusted to be a real location before * generate_code() time. */ struct brw_reg fs_visitor::interp_reg(int location, int channel) { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data; int regnr = prog_data->urb_setup[location] * 2 + channel / 2; int stride = (channel & 1) * 4; assert(prog_data->urb_setup[location] != -1); return brw_vec1_grf(regnr, stride); } /** Emits the interpolation for the varying inputs. */ void fs_visitor::emit_interpolation_setup_gen4() { struct brw_reg g1_uw = retype(brw_vec1_grf(1, 0), BRW_REGISTER_TYPE_UW); fs_builder abld = bld.annotate("compute pixel centers"); this->pixel_x = vgrf(glsl_type::uint_type); this->pixel_y = vgrf(glsl_type::uint_type); this->pixel_x.type = BRW_REGISTER_TYPE_UW; this->pixel_y.type = BRW_REGISTER_TYPE_UW; abld.ADD(this->pixel_x, fs_reg(stride(suboffset(g1_uw, 4), 2, 4, 0)), fs_reg(brw_imm_v(0x10101010))); abld.ADD(this->pixel_y, fs_reg(stride(suboffset(g1_uw, 5), 2, 4, 0)), fs_reg(brw_imm_v(0x11001100))); abld = bld.annotate("compute pixel deltas from v0"); this->delta_xy[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC] = vgrf(glsl_type::vec2_type); const fs_reg &delta_xy = this->delta_xy[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC]; const fs_reg xstart(negate(brw_vec1_grf(1, 0))); const fs_reg ystart(negate(brw_vec1_grf(1, 1))); if (devinfo->has_pln && dispatch_width == 16) { for (unsigned i = 0; i < 2; i++) { abld.half(i).ADD(half(offset(delta_xy, abld, i), 0), half(this->pixel_x, i), xstart); abld.half(i).ADD(half(offset(delta_xy, abld, i), 1), half(this->pixel_y, i), ystart); } } else { abld.ADD(offset(delta_xy, abld, 0), this->pixel_x, xstart); abld.ADD(offset(delta_xy, abld, 1), this->pixel_y, ystart); } abld = bld.annotate("compute pos.w and 1/pos.w"); /* Compute wpos.w. It's always in our setup, since it's needed to * interpolate the other attributes. */ this->wpos_w = vgrf(glsl_type::float_type); abld.emit(FS_OPCODE_LINTERP, wpos_w, delta_xy, interp_reg(VARYING_SLOT_POS, 3)); /* Compute the pixel 1/W value from wpos.w. */ this->pixel_w = vgrf(glsl_type::float_type); abld.emit(SHADER_OPCODE_RCP, this->pixel_w, wpos_w); } /** Emits the interpolation for the varying inputs. */ void fs_visitor::emit_interpolation_setup_gen6() { struct brw_reg g1_uw = retype(brw_vec1_grf(1, 0), BRW_REGISTER_TYPE_UW); fs_builder abld = bld.annotate("compute pixel centers"); if (devinfo->gen >= 8 || dispatch_width == 8) { /* The "Register Region Restrictions" page says for BDW (and newer, * presumably): * * "When destination spans two registers, the source may be one or * two registers. The destination elements must be evenly split * between the two registers." * * Thus we can do a single add(16) in SIMD8 or an add(32) in SIMD16 to * compute our pixel centers. */ fs_reg int_pixel_xy(GRF, alloc.allocate(dispatch_width / 8), BRW_REGISTER_TYPE_UW); const fs_builder dbld = abld.exec_all().group(dispatch_width * 2, 0); dbld.ADD(int_pixel_xy, fs_reg(stride(suboffset(g1_uw, 4), 1, 4, 0)), fs_reg(brw_imm_v(0x11001010))); this->pixel_x = vgrf(glsl_type::float_type); this->pixel_y = vgrf(glsl_type::float_type); abld.emit(FS_OPCODE_PIXEL_X, this->pixel_x, int_pixel_xy); abld.emit(FS_OPCODE_PIXEL_Y, this->pixel_y, int_pixel_xy); } else { /* The "Register Region Restrictions" page says for SNB, IVB, HSW: * * "When destination spans two registers, the source MUST span two * registers." * * Since the GRF source of the ADD will only read a single register, we * must do two separate ADDs in SIMD16. */ fs_reg int_pixel_x = vgrf(glsl_type::uint_type); fs_reg int_pixel_y = vgrf(glsl_type::uint_type); int_pixel_x.type = BRW_REGISTER_TYPE_UW; int_pixel_y.type = BRW_REGISTER_TYPE_UW; abld.ADD(int_pixel_x, fs_reg(stride(suboffset(g1_uw, 4), 2, 4, 0)), fs_reg(brw_imm_v(0x10101010))); abld.ADD(int_pixel_y, fs_reg(stride(suboffset(g1_uw, 5), 2, 4, 0)), fs_reg(brw_imm_v(0x11001100))); /* As of gen6, we can no longer mix float and int sources. We have * to turn the integer pixel centers into floats for their actual * use. */ this->pixel_x = vgrf(glsl_type::float_type); this->pixel_y = vgrf(glsl_type::float_type); abld.MOV(this->pixel_x, int_pixel_x); abld.MOV(this->pixel_y, int_pixel_y); } abld = bld.annotate("compute pos.w"); this->pixel_w = fs_reg(brw_vec8_grf(payload.source_w_reg, 0)); this->wpos_w = vgrf(glsl_type::float_type); abld.emit(SHADER_OPCODE_RCP, this->wpos_w, this->pixel_w); for (int i = 0; i < BRW_WM_BARYCENTRIC_INTERP_MODE_COUNT; ++i) { uint8_t reg = payload.barycentric_coord_reg[i]; this->delta_xy[i] = fs_reg(brw_vec16_grf(reg, 0)); } } static enum brw_conditional_mod cond_for_alpha_func(GLenum func) { switch(func) { case GL_GREATER: return BRW_CONDITIONAL_G; case GL_GEQUAL: return BRW_CONDITIONAL_GE; case GL_LESS: return BRW_CONDITIONAL_L; case GL_LEQUAL: return BRW_CONDITIONAL_LE; case GL_EQUAL: return BRW_CONDITIONAL_EQ; case GL_NOTEQUAL: return BRW_CONDITIONAL_NEQ; default: unreachable("Not reached"); } } /** * Alpha test support for when we compile it into the shader instead * of using the normal fixed-function alpha test. */ void fs_visitor::emit_alpha_test() { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; const fs_builder abld = bld.annotate("Alpha test"); fs_inst *cmp; if (key->alpha_test_func == GL_ALWAYS) return; if (key->alpha_test_func == GL_NEVER) { /* f0.1 = 0 */ fs_reg some_reg = fs_reg(retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UW)); cmp = abld.CMP(bld.null_reg_f(), some_reg, some_reg, BRW_CONDITIONAL_NEQ); } else { /* RT0 alpha */ fs_reg color = offset(outputs[0], bld, 3); /* f0.1 &= func(color, ref) */ cmp = abld.CMP(bld.null_reg_f(), color, fs_reg(key->alpha_test_ref), cond_for_alpha_func(key->alpha_test_func)); } cmp->predicate = BRW_PREDICATE_NORMAL; cmp->flag_subreg = 1; } fs_inst * fs_visitor::emit_single_fb_write(const fs_builder &bld, fs_reg color0, fs_reg color1, fs_reg src0_alpha, unsigned components) { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data; /* Hand over gl_FragDepth or the payload depth. */ const fs_reg dst_depth = (payload.dest_depth_reg ? fs_reg(brw_vec8_grf(payload.dest_depth_reg, 0)) : fs_reg()); fs_reg src_depth; if (source_depth_to_render_target) { if (prog->OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) src_depth = frag_depth; else src_depth = fs_reg(brw_vec8_grf(payload.source_depth_reg, 0)); } const fs_reg sources[] = { color0, color1, src0_alpha, src_depth, dst_depth, sample_mask, fs_reg(components) }; fs_inst *write = bld.emit(FS_OPCODE_FB_WRITE_LOGICAL, fs_reg(), sources, ARRAY_SIZE(sources)); if (prog_data->uses_kill) { write->predicate = BRW_PREDICATE_NORMAL; write->flag_subreg = 1; } return write; } void fs_visitor::emit_fb_writes() { assert(stage == MESA_SHADER_FRAGMENT); brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data; brw_wm_prog_key *key = (brw_wm_prog_key*) this->key; fs_inst *inst = NULL; if (source_depth_to_render_target && devinfo->gen == 6) { /* For outputting oDepth on gen6, SIMD8 writes have to be used. This * would require SIMD8 moves of each half to message regs, e.g. by using * the SIMD lowering pass. Unfortunately this is more difficult than it * sounds because the SIMD8 single-source message lacks channel selects * for the second and third subspans. */ no16("Missing support for simd16 depth writes on gen6\n"); } if (do_dual_src) { const fs_builder abld = bld.annotate("FB dual-source write"); inst = emit_single_fb_write(abld, this->outputs[0], this->dual_src_output, reg_undef, 4); inst->target = 0; prog_data->dual_src_blend = true; } else { for (int target = 0; target < key->nr_color_regions; target++) { /* Skip over outputs that weren't written. */ if (this->outputs[target].file == BAD_FILE) continue; const fs_builder abld = bld.annotate( ralloc_asprintf(this->mem_ctx, "FB write target %d", target)); fs_reg src0_alpha; if (devinfo->gen >= 6 && key->replicate_alpha && target != 0) src0_alpha = offset(outputs[0], bld, 3); inst = emit_single_fb_write(abld, this->outputs[target], reg_undef, src0_alpha, this->output_components[target]); inst->target = target; } } if (inst == NULL) { /* Even if there's no color buffers enabled, we still need to send * alpha out the pipeline to our null renderbuffer to support * alpha-testing, alpha-to-coverage, and so on. */ /* FINISHME: Factor out this frequently recurring pattern into a * helper function. */ const fs_reg srcs[] = { reg_undef, reg_undef, reg_undef, offset(this->outputs[0], bld, 3) }; const fs_reg tmp = bld.vgrf(BRW_REGISTER_TYPE_UD, 4); bld.LOAD_PAYLOAD(tmp, srcs, 4, 0); inst = emit_single_fb_write(bld, tmp, reg_undef, reg_undef, 4); inst->target = 0; } inst->eot = true; } void fs_visitor::setup_uniform_clipplane_values(gl_clip_plane *clip_planes) { const struct brw_vue_prog_key *key = (const struct brw_vue_prog_key *) this->key; for (int i = 0; i < key->nr_userclip_plane_consts; i++) { this->userplane[i] = fs_reg(UNIFORM, uniforms); for (int j = 0; j < 4; ++j) { stage_prog_data->param[uniforms + j] = (gl_constant_value *) &clip_planes[i][j]; } uniforms += 4; } } /** * Lower legacy fixed-function and gl_ClipVertex clipping to clip distances. * * This does nothing if the shader uses gl_ClipDistance or user clipping is * disabled altogether. */ void fs_visitor::compute_clip_distance(gl_clip_plane *clip_planes) { struct brw_vue_prog_data *vue_prog_data = (struct brw_vue_prog_data *) prog_data; const struct brw_vue_prog_key *key = (const struct brw_vue_prog_key *) this->key; /* Bail unless some sort of legacy clipping is enabled */ if (!key->userclip_active || prog->UsesClipDistanceOut) return; /* From the GLSL 1.30 spec, section 7.1 (Vertex Shader Special Variables): * * "If a linked set of shaders forming the vertex stage contains no * static write to gl_ClipVertex or gl_ClipDistance, but the * application has requested clipping against user clip planes through * the API, then the coordinate written to gl_Position is used for * comparison against the user clip planes." * * This function is only called if the shader didn't write to * gl_ClipDistance. Accordingly, we use gl_ClipVertex to perform clipping * if the user wrote to it; otherwise we use gl_Position. */ gl_varying_slot clip_vertex = VARYING_SLOT_CLIP_VERTEX; if (!(vue_prog_data->vue_map.slots_valid & VARYING_BIT_CLIP_VERTEX)) clip_vertex = VARYING_SLOT_POS; /* If the clip vertex isn't written, skip this. Typically this means * the GS will set up clipping. */ if (outputs[clip_vertex].file == BAD_FILE) return; setup_uniform_clipplane_values(clip_planes); const fs_builder abld = bld.annotate("user clip distances"); this->outputs[VARYING_SLOT_CLIP_DIST0] = vgrf(glsl_type::vec4_type); this->outputs[VARYING_SLOT_CLIP_DIST1] = vgrf(glsl_type::vec4_type); for (int i = 0; i < key->nr_userclip_plane_consts; i++) { fs_reg u = userplane[i]; fs_reg output = outputs[VARYING_SLOT_CLIP_DIST0 + i / 4]; output.reg_offset = i & 3; abld.MUL(output, outputs[clip_vertex], u); for (int j = 1; j < 4; j++) { u.reg = userplane[i].reg + j; abld.MAD(output, output, offset(outputs[clip_vertex], bld, j), u); } } } void fs_visitor::emit_urb_writes() { int slot, urb_offset, length; struct brw_vs_prog_data *vs_prog_data = (struct brw_vs_prog_data *) prog_data; const struct brw_vs_prog_key *key = (const struct brw_vs_prog_key *) this->key; const GLbitfield64 psiz_mask = VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT | VARYING_BIT_PSIZ; const struct brw_vue_map *vue_map = &vs_prog_data->base.vue_map; bool flush; fs_reg sources[8]; /* If we don't have any valid slots to write, just do a minimal urb write * send to terminate the shader. This includes 1 slot of undefined data, * because it's invalid to write 0 data: * * From the Broadwell PRM, Volume 7: 3D Media GPGPU, Shared Functions - * Unified Return Buffer (URB) > URB_SIMD8_Write and URB_SIMD8_Read > * Write Data Payload: * * "The write data payload can be between 1 and 8 message phases long." */ if (vue_map->slots_valid == 0) { fs_reg payload = fs_reg(GRF, alloc.allocate(2), BRW_REGISTER_TYPE_UD); bld.exec_all().MOV(payload, fs_reg(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD))); fs_inst *inst = bld.emit(SHADER_OPCODE_URB_WRITE_SIMD8, reg_undef, payload); inst->eot = true; inst->mlen = 2; inst->offset = 1; return; } length = 0; urb_offset = 0; flush = false; for (slot = 0; slot < vue_map->num_slots; slot++) { fs_reg reg, src, zero; int varying = vue_map->slot_to_varying[slot]; switch (varying) { case VARYING_SLOT_PSIZ: /* The point size varying slot is the vue header and is always in the * vue map. But often none of the special varyings that live there * are written and in that case we can skip writing to the vue * header, provided the corresponding state properly clamps the * values further down the pipeline. */ if ((vue_map->slots_valid & psiz_mask) == 0) { assert(length == 0); urb_offset++; break; } zero = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); bld.MOV(zero, fs_reg(0u)); sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_LAYER) sources[length++] = this->outputs[VARYING_SLOT_LAYER]; else sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_VIEWPORT) sources[length++] = this->outputs[VARYING_SLOT_VIEWPORT]; else sources[length++] = zero; if (vue_map->slots_valid & VARYING_BIT_PSIZ) sources[length++] = this->outputs[VARYING_SLOT_PSIZ]; else sources[length++] = zero; break; case BRW_VARYING_SLOT_NDC: case VARYING_SLOT_EDGE: unreachable("unexpected scalar vs output"); break; case BRW_VARYING_SLOT_PAD: break; default: /* gl_Position is always in the vue map, but isn't always written by * the shader. Other varyings (clip distances) get added to the vue * map but don't always get written. In those cases, the * corresponding this->output[] slot will be invalid we and can skip * the urb write for the varying. If we've already queued up a vue * slot for writing we flush a mlen 5 urb write, otherwise we just * advance the urb_offset. */ if (this->outputs[varying].file == BAD_FILE) { if (length > 0) flush = true; else urb_offset++; break; } if ((varying == VARYING_SLOT_COL0 || varying == VARYING_SLOT_COL1 || varying == VARYING_SLOT_BFC0 || varying == VARYING_SLOT_BFC1) && key->clamp_vertex_color) { /* We need to clamp these guys, so do a saturating MOV into a * temp register and use that for the payload. */ for (int i = 0; i < 4; i++) { reg = fs_reg(GRF, alloc.allocate(1), outputs[varying].type); src = offset(this->outputs[varying], bld, i); set_saturate(true, bld.MOV(reg, src)); sources[length++] = reg; } } else { for (int i = 0; i < 4; i++) sources[length++] = offset(this->outputs[varying], bld, i); } break; } const fs_builder abld = bld.annotate("URB write"); /* If we've queued up 8 registers of payload (2 VUE slots), if this is * the last slot or if we need to flush (see BAD_FILE varying case * above), emit a URB write send now to flush out the data. */ int last = slot == vue_map->num_slots - 1; if (length == 8 || last) flush = true; if (flush) { fs_reg *payload_sources = ralloc_array(mem_ctx, fs_reg, length + 1); fs_reg payload = fs_reg(GRF, alloc.allocate(length + 1), BRW_REGISTER_TYPE_F); payload_sources[0] = fs_reg(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD)); memcpy(&payload_sources[1], sources, length * sizeof sources[0]); abld.LOAD_PAYLOAD(payload, payload_sources, length + 1, 1); fs_inst *inst = abld.emit(SHADER_OPCODE_URB_WRITE_SIMD8, reg_undef, payload); inst->eot = last; inst->mlen = length + 1; inst->offset = urb_offset; urb_offset = slot + 1; length = 0; flush = false; } } } void fs_visitor::emit_cs_terminate() { assert(devinfo->gen >= 7); /* We are getting the thread ID from the compute shader header */ assert(stage == MESA_SHADER_COMPUTE); /* We can't directly send from g0, since sends with EOT have to use * g112-127. So, copy it to a virtual register, The register allocator will * make sure it uses the appropriate register range. */ struct brw_reg g0 = retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD); fs_reg payload = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); bld.group(8, 0).exec_all().MOV(payload, g0); /* Send a message to the thread spawner to terminate the thread. */ fs_inst *inst = bld.exec_all() .emit(CS_OPCODE_CS_TERMINATE, reg_undef, payload); inst->eot = true; } void fs_visitor::emit_barrier() { assert(devinfo->gen >= 7); /* We are getting the barrier ID from the compute shader header */ assert(stage == MESA_SHADER_COMPUTE); fs_reg payload = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD); /* Clear the message payload */ bld.exec_all().MOV(payload, fs_reg(0u)); /* Copy bits 27:24 of r0.2 (barrier id) to the message payload reg.2 */ fs_reg r0_2 = fs_reg(retype(brw_vec1_grf(0, 2), BRW_REGISTER_TYPE_UD)); bld.exec_all().AND(component(payload, 2), r0_2, fs_reg(0x0f000000u)); /* Emit a gateway "barrier" message using the payload we set up, followed * by a wait instruction. */ bld.exec_all().emit(SHADER_OPCODE_BARRIER, reg_undef, payload); } fs_visitor::fs_visitor(const struct brw_compiler *compiler, void *log_data, void *mem_ctx, gl_shader_stage stage, const void *key, struct brw_stage_prog_data *prog_data, struct gl_shader_program *shader_prog, struct gl_program *prog, unsigned dispatch_width, int shader_time_index) : backend_shader(compiler, log_data, mem_ctx, shader_prog, prog, prog_data, stage), key(key), prog_data(prog_data), dispatch_width(dispatch_width), shader_time_index(shader_time_index), promoted_constants(0), bld(fs_builder(this, dispatch_width).at_end()) { switch (stage) { case MESA_SHADER_FRAGMENT: key_tex = &((const brw_wm_prog_key *) key)->tex; break; case MESA_SHADER_VERTEX: case MESA_SHADER_GEOMETRY: key_tex = &((const brw_vue_prog_key *) key)->tex; break; case MESA_SHADER_COMPUTE: key_tex = &((const brw_cs_prog_key*) key)->tex; break; default: unreachable("unhandled shader stage"); } this->failed = false; this->simd16_unsupported = false; this->no16_msg = NULL; this->nir_locals = NULL; this->nir_ssa_values = NULL; memset(&this->payload, 0, sizeof(this->payload)); memset(this->outputs, 0, sizeof(this->outputs)); memset(this->output_components, 0, sizeof(this->output_components)); this->source_depth_to_render_target = false; this->runtime_check_aads_emit = false; this->first_non_payload_grf = 0; this->max_grf = devinfo->gen >= 7 ? GEN7_MRF_HACK_START : BRW_MAX_GRF; this->virtual_grf_start = NULL; this->virtual_grf_end = NULL; this->live_intervals = NULL; this->regs_live_at_ip = NULL; this->uniforms = 0; this->last_scratch = 0; this->pull_constant_loc = NULL; this->push_constant_loc = NULL; this->spilled_any_registers = false; this->do_dual_src = false; if (dispatch_width == 8) this->param_size = rzalloc_array(mem_ctx, int, stage_prog_data->nr_params); } fs_visitor::~fs_visitor() { }