From 75afe17b7954984ea5b55c2a6d5d124f5eb03328 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Fri, 26 Sep 2014 14:47:03 -0700 Subject: [PATCH] i965/fs: Manually generate the meta fast-clear shader MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Previously, we were generating the fast-clear shader from GLSL. The problem is that fast clears require that we use a replicated write rather than a regular write instruction. In order to get this we had a complicated and somewhat fragile optimization pass that looked for places where we can use a replicated write and used it. Since replicated writes have a lot of restrictions, we only ever use them for fast-clear operations. This commit replaces the optimization pass with a function that just generates the shader we want. This is a) less code, b) less fragile than the optimization pass, and c) generates a more efficient shader. Signed-off-by: Jason Ekstrand Reviewed-by: Kristian Høgsberg Acked-by: Kenneth Graunke --- src/mesa/drivers/dri/i965/brw_fs.cpp | 122 ++++++++------------------- src/mesa/drivers/dri/i965/brw_fs.h | 3 +- 2 files changed, 35 insertions(+), 90 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index ffe8ba89497..f3c39e7cdb4 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -2329,98 +2329,44 @@ fs_visitor::compute_to_mrf() * instructions to FS_OPCODE_REP_FB_WRITE. */ void -fs_visitor::try_rep_send() +fs_visitor::emit_repclear_shader() { - int i, count; - fs_inst *start = NULL; - bblock_t *mov_block; + int base_mrf = 1; + int color_mrf = base_mrf + 2; - /* From the Ivybridge PRM, Volume 4 Part 1, section 3.9.11.2 - * ("Message Descriptor - Render Target Write"): - * - * "SIMD16_REPDATA message must not be used in SIMD8 pixel-shaders." - */ - if (dispatch_width != 16) - return; - - /* The constant color write message can't handle anything but the 4 color - * values. We could do MRT, but the loops below would need to understand - * handling the header being enabled or disabled on different messages. It - * also requires that the render target be tiled, which might not be the - * case for some EGLImage paths or if we some day do rendering to PBOs. - */ - if (prog->OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH) || - payload.aa_dest_stencil_reg || - payload.dest_depth_reg || - dual_src_output.file != BAD_FILE) - return; + fs_inst *mov = emit(MOV(vec4(brw_message_reg(color_mrf)), + fs_reg(UNIFORM, 0, BRW_REGISTER_TYPE_F))); + mov->force_writemask_all = true; + mov->force_uncompressed = true; - /* The optimization is implemented as one pass through the instruction - * list. We keep track of the most recent block of MOVs into sequential - * MRFs from single, sequential float registers (ie uniforms). Then when - * we find an FB_WRITE opcode, we see if the payload registers match the - * destination registers in our block of MOVs. - */ - count = 0; - foreach_block_and_inst_safe(block, fs_inst, inst, cfg) { - if (count == 0) { - start = inst; - mov_block = block; - } - if (inst->opcode == BRW_OPCODE_MOV && - inst->dst.file == MRF && - inst->dst.reg == start->dst.reg + 2 * count && - inst->src[0].file == HW_REG && - inst->src[0].reg_offset == start->src[0].reg_offset + count) { - if (count == 0) { - start = inst; - mov_block = block; - } - count++; + fs_inst *write; + if (key->nr_color_regions == 1) { + write = emit(FS_OPCODE_REP_FB_WRITE); + write->saturate = key->clamp_fragment_color; + write->base_mrf = color_mrf; + write->target = 0; + write->header_present = false; + write->mlen = 1; + } else { + for (int i = 0; i < key->nr_color_regions; ++i) { + write = emit(FS_OPCODE_REP_FB_WRITE); + write->saturate = key->clamp_fragment_color; + write->base_mrf = base_mrf; + write->target = i; + write->header_present = true; + write->mlen = 3; } + } + write->eot = true; - if (inst->opcode == FS_OPCODE_FB_WRITE && - count == 4 && - (inst->base_mrf == start->dst.reg || - (inst->base_mrf + 2 == start->dst.reg && inst->header_present))) { - fs_inst *mov = MOV(start->dst, start->src[0]); + calculate_cfg(); - /* Make a MOV that moves the four floats into the replicated write - * payload. Since we're running at the very end of code generation - * we can use hw registers and generate the stride and offsets we - * need for this MOV. We use the first of the eight registers - * allocated for the SIMD16 payload for the four floats. - */ - mov->dst.fixed_hw_reg = - brw_vec4_reg(BRW_MESSAGE_REGISTER_FILE, - start->dst.reg, 0); - mov->dst.file = HW_REG; - mov->dst.type = mov->dst.fixed_hw_reg.type; - - mov->src[0].fixed_hw_reg = - brw_vec4_grf(mov->src[0].fixed_hw_reg.nr, 0); - mov->src[0].file = HW_REG; - mov->src[0].type = mov->src[0].fixed_hw_reg.type; - mov->force_writemask_all = true; - mov->dst.type = BRW_REGISTER_TYPE_F; - - /* Replace the four MOVs with the new vec4 MOV. */ - start->insert_before(mov_block, mov); - for (i = 0; i < 4; i++) - ((fs_inst *) mov->next)->remove(mov_block); - - /* Finally, adjust the message length and set the opcode to - * REP_FB_WRITE for the send, so that the generator will use the - * replicated data mesage type. Then reset count so we'll start - * looking for a new block in case we're in a MRT shader. - */ - inst->opcode = FS_OPCODE_REP_FB_WRITE; - inst->mlen -= 7; - count = 0; - } - } + assign_constant_locations(); + assign_curb_setup(); - return; + /* Now that we have the uniform assigned, go ahead and force it to a vec4. */ + assert(mov->src[0].file == HW_REG); + mov->src[0] = brw_vec4_grf(mov->src[0].fixed_hw_reg.nr, 0); } /** @@ -3199,6 +3145,9 @@ fs_visitor::run() if (0) { emit_dummy_fs(); + } else if (brw->use_rep_send && dispatch_width == 16) { + emit_repclear_shader(); + allocated_without_spills = true; } else { if (INTEL_DEBUG & DEBUG_SHADER_TIME) emit_shader_time_begin(); @@ -3379,9 +3328,6 @@ fs_visitor::run() prog_data->total_scratch = brw_get_scratch_size(last_scratch); } - if (brw->use_rep_send) - try_rep_send(); - if (stage == MESA_SHADER_FRAGMENT) { brw_wm_prog_data *prog_data = (brw_wm_prog_data*) this->prog_data; if (dispatch_width == 8) diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h index f8bc46c710a..108e5b34d9f 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.h +++ b/src/mesa/drivers/dri/i965/brw_fs.h @@ -358,12 +358,11 @@ public: void lower_uniform_pull_constant_loads(); bool lower_load_payload(); - void try_rep_send(); - void push_force_uncompressed(); void pop_force_uncompressed(); void emit_dummy_fs(); + void emit_repclear_shader(); fs_reg *emit_fragcoord_interpolation(ir_variable *ir); fs_inst *emit_linterp(const fs_reg &attr, const fs_reg &interp, glsl_interp_qualifier interpolation_mode, -- 2.30.2