<div dir="ltr">Nice! This may let us delete some back-end code too. I'll review later. </div><div class="gmail_extra"> <div class="gmail_quote">On Thu, Apr 13, 2017 at 8:23 AM, Rob Clark <<a href="mailto:robdclark@gmail.com" target="_blank">robdclark@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">This is equivalent to what mesa/st does in glsl_to_tgsi. For most hw there isn't a particularly good reason to treat these differently. Signed-off-by: Rob Clark <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> --- This is part of a larger patchset I'm working on to add SSBO and compute shader support in mesa/st glsl_to_nir path, and compute/SSBO support in freedreno. Still working on a few things and some cleanup on the rest of it, but I figured I should send this out to get some early comments. src/compiler/Makefile.sources | 1 + src/compiler/nir/nir.h | 1 + src/compiler/nir/nir_lower_atomics_to_ssbo.c | 215 +++++++++++++++++++++++++++ 3 files changed, 217 insertions(+) create mode 100644 src/compiler/nir/nir_lower_atomics_to_ssbo.c diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources index 2455d4e..b2a3a42 100644 --- a/src/compiler/Makefile.sources +++ b/src/compiler/Makefile.sources @@ -208,6 +208,7 @@ NIR_FILES = \ nir/nir_lower_64bit_packing.c \ nir/nir_lower_alu_to_scalar.c \ nir/nir_lower_atomics.c \ + nir/nir_lower_atomics_to_ssbo.c \ nir/nir_lower_bitmap.c \ nir/nir_lower_clamp_color_outputs.c \ nir/nir_lower_clip.c \ diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h index ce5b434..be35930 100644 --- a/src/compiler/nir/nir.h +++ b/src/compiler/nir/nir.h @@ -2546,6 +2546,7 @@ void nir_lower_bitmap(nir_shader *shader, const nir_lower_bitmap_options *option bool nir_lower_atomics(nir_shader *shader, const struct gl_shader_program *shader_program); +bool nir_lower_atomics_to_ssbo(nir_shader *shader, unsigned ssbo_offset); bool nir_lower_to_source_mods(nir_shader *shader); bool nir_lower_gs_intrinsics(nir_shader *shader); diff --git a/src/compiler/nir/nir_lower_atomics_to_ssbo.c b/src/compiler/nir/nir_lower_atomics_to_ssbo.c new file mode 100644 index 0000000..f382e29 --- /dev/null +++ b/src/compiler/nir/nir_lower_atomics_to_ssbo.c @@ -0,0 +1,215 @@ +/* + * Copyright © 2017 Red Hat + * + * 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. + * + * Authors: + * Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> + */ + +#include "nir.h" +#include "nir_builder.h" + +/* + * Remap atomic counters to SSBOs. Atomic counters get remapped to + * SSBO binding points [0..ssbo_offset) and the original SSBOs are + * remapped to [ssbo_offset..n) (mostly to align with what mesa/st + * does. + */ + +static bool +lower_instr(nir_intrinsic_instr *instr, unsigned ssbo_offset, nir_builder *b) +{ + nir_intrinsic_op op; + switch (instr->intrinsic) { + case nir_intrinsic_ssbo_atomic_add: + case nir_intrinsic_ssbo_atomic_imin: + case nir_intrinsic_ssbo_atomic_umin: + case nir_intrinsic_ssbo_atomic_imax: + case nir_intrinsic_ssbo_atomic_umax: + case nir_intrinsic_ssbo_atomic_and: + case nir_intrinsic_ssbo_atomic_or: + case nir_intrinsic_ssbo_atomic_xor: + case nir_intrinsic_ssbo_atomic_exchange: + case nir_intrinsic_ssbo_atomic_comp_swap: + case nir_intrinsic_store_ssbo: + case nir_intrinsic_load_ssbo: + /* keep same opcode, remap buffer_index */ + op = instr->intrinsic; + break; + case nir_intrinsic_atomic_counter_inc: + case nir_intrinsic_atomic_counter_add: + case nir_intrinsic_atomic_counter_dec: + /* inc and dec get remapped to add: */ + op = nir_intrinsic_ssbo_atomic_add; + break; + case nir_intrinsic_atomic_counter_read: + op = nir_intrinsic_load_ssbo; + break; + case nir_intrinsic_atomic_counter_min: + op = nir_intrinsic_ssbo_atomic_umin; + break; + case nir_intrinsic_atomic_counter_max: + op = nir_intrinsic_ssbo_atomic_umax; + break; + case nir_intrinsic_atomic_counter_and: + op = nir_intrinsic_ssbo_atomic_and; + break; + case nir_intrinsic_atomic_counter_or: + op = nir_intrinsic_ssbo_atomic_or; + break; + case nir_intrinsic_atomic_counter_xor: + op = nir_intrinsic_ssbo_atomic_xor; + break; + case nir_intrinsic_atomic_counter_exchange: + op = nir_intrinsic_ssbo_atomic_exchange; + break; + case nir_intrinsic_atomic_counter_comp_swap: + op = nir_intrinsic_ssbo_atomic_comp_swap; + break; + default: + return false; + } + + b->cursor = nir_before_instr(&instr->instr); + + /* easy case, just remap SSBO buffer index: */ + if (op == instr->intrinsic) { + unsigned srcn = (op == nir_intrinsic_store_ssbo) ? 1 : 0; + nir_ssa_def *old_idx = nir_ssa_for_src(b, instr->src[srcn], 1); + nir_ssa_def *new_idx = nir_iadd(b, old_idx, nir_imm_int(b, ssbo_offset)); + nir_instr_rewrite_src(&instr->instr, + &instr->src[srcn], + nir_src_for_ssa(new_idx)); + + return true; + } + + nir_ssa_def *buffer = nir_imm_int(b, nir_intrinsic_base(instr)); + nir_ssa_def *temp = NULL; + nir_intrinsic_instr *new_instr = + nir_intrinsic_instr_create(ralloc_parent(instr), op); + + /* a couple instructions need special handling since they don't map + * 1:1 with ssbo atomics + */ + switch (instr->intrinsic) { + case nir_intrinsic_atomic_counter_inc: + /* remapped to ssbo_atomic_add: { buffer_idx, offset, +1 } */ + temp = nir_imm_int(b, +1); + new_instr->src[0] = nir_src_for_ssa(buffer); + new_instr->src[1] = instr->src[0]; + new_instr->src[2] = nir_src_for_ssa(temp); + break; + case nir_intrinsic_atomic_counter_dec: + /* remapped to ssbo_atomic_add: { buffer_idx, offset, -1 } */ + /* NOTE semantic difference so we adjust the return value below */ + temp = nir_imm_int(b, -1); + new_instr->src[0] = nir_src_for_ssa(buffer); + new_instr->src[1] = instr->src[0]; + new_instr->src[2] = nir_src_for_ssa(temp); + break; + case nir_intrinsic_atomic_counter_read: + /* remapped to load_ssbo: { buffer_idx, offset } */ + new_instr->src[0] = nir_src_for_ssa(buffer); + new_instr->src[1] = instr->src[0]; + break; + default: + /* remapped to ssbo_atomic_x: { buffer_idx, offset, data, (compare)? } */ + new_instr->src[0] = nir_src_for_ssa(buffer); + new_instr->src[1] = instr->src[0]; + new_instr->src[2] = instr->src[1]; + if (op == nir_intrinsic_ssbo_atomic_comp_swap) + new_instr->src[3] = instr->src[2]; + break; + } + + nir_ssa_dest_init(&new_instr->instr, &new_instr->dest, + instr->dest.ssa.num_components, + instr->dest.ssa.bit_size, NULL); + nir_instr_insert_before(&instr->instr, &new_instr->instr); + nir_instr_remove(&instr->instr); + + if (instr->intrinsic == nir_intrinsic_atomic_counter_dec) { + b->cursor = nir_after_instr(&new_instr->instr); + nir_ssa_def *result = nir_iadd(b, &new_instr->dest.ssa, temp); + nir_ssa_def_rewrite_uses(&instr->dest.ssa, nir_src_for_ssa(result)); + } else { + nir_ssa_def_rewrite_uses(&instr->dest.ssa, nir_src_for_ssa(&new_instr->dest.ssa)); + } + + return true; +} + +bool +nir_lower_atomics_to_ssbo(nir_shader *shader, unsigned ssbo_offset) +{ + bool progress = false; + + nir_foreach_function(function, shader) { + if (function->impl) { + nir_builder builder; + nir_builder_init(&builder, function->impl); + nir_foreach_block(block, function->impl) { + nir_foreach_instr_safe(instr, block) { + if (instr->type == nir_instr_type_intrinsic) + progress |= lower_instr(nir_instr_as_intrinsic(instr), + ssbo_offset, &builder); + } + } + + nir_metadata_preserve(function->impl, nir_metadata_block_index | + nir_metadata_dominance); + } + } + + if (progress) { + /* replace atomic_uint uniforms with ssbo's: */ + unsigned replaced = 0; + nir_foreach_variable_safe(var, &shader->uniforms) { + if (glsl_get_base_type(var->type) == GLSL_TYPE_ATOMIC_UINT) { + exec_node_remove(&var->node); + + if (replaced & (1 << var->data.binding)) + continue; + + nir_variable *ssbo; + char name[16]; + + // TODO can we declare an array without size? Or do we have + // to find all the atomic_uint's in one pass and figure out + // max offset?? + const struct glsl_type *type = + glsl_array_type(glsl_uint_type(), 256); + + snprintf(name, sizeof(name), "counter%d", var->data.binding); + + ssbo = nir_variable_create(shader, nir_var_shader_storage, + type, name); + ssbo->data.binding = var->data.binding; + + replaced |= (1 << var->data.binding); + } + } + } + + return progress; +} + -- 2.9.3 </blockquote></div> </div>