<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Sat, May 14, 2016 at 12:23 PM, 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"><div class="HOEnZb"><div class="h5">On Thu, May 12, 2016 at 10:17 PM, Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> wrote: > > > On Mon, May 9, 2016 at 12:33 PM, Rob Clark <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> wrote: >> >> From: Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> >> >> Signed-off-by: Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> >> Reviewed-by: Connor Abbott <<a href="mailto:cwabbott0@gmail.com">cwabbott0@gmail.com</a>> >> --- >> src/compiler/Makefile.sources | 1 + >> src/compiler/nir/nir.h | 11 + >> src/compiler/nir/nir_lower_wpos_ytransform.c | 310 >> +++++++++++++++++++++++++++ >> 3 files changed, 322 insertions(+) >> create mode 100644 src/compiler/nir/nir_lower_wpos_ytransform.c >> >> diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources >> index 2a52319..b542a1a 100644 >> --- a/src/compiler/Makefile.sources >> +++ b/src/compiler/Makefile.sources >> @@ -208,6 +208,7 @@ NIR_FILES = \ >> nir/nir_lower_vars_to_ssa.c \ >> nir/nir_lower_var_copies.c \ >> nir/nir_lower_vec_to_movs.c \ >> + nir/nir_lower_wpos_ytransform.c \ >> nir/nir_metadata.c \ >> nir/nir_move_vec_src_uses_to_dest.c \ >> nir/nir_normalize_cubemap_coords.c \ >> diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h >> index 8a616d4..474ba63 100644 >> --- a/src/compiler/nir/nir.h >> +++ b/src/compiler/nir/nir.h >> @@ -2374,6 +2374,17 @@ void nir_lower_two_sided_color(nir_shader *shader); >> >> void nir_lower_clamp_color_outputs(nir_shader *shader); >> >> +typedef struct nir_lower_wpos_ytransform_options { >> + int state_tokens[5]; >> + bool fs_coord_origin_upper_left :1; >> + bool fs_coord_origin_lower_left :1; >> + bool fs_coord_pixel_center_integer :1; >> + bool fs_coord_pixel_center_half_integer :1; > > > Drive-by commentary: Why are we using two booleans for one boolean here? > All hardware should be either lower-left or upper-left and I'm going to > hazard that the other two are mutually exclusive as well. The pass > certainly seems to assume so. </div></div>mostly just because gallium splits it out into two caps, and this matches the logic in the equiv tgsi lowering pass more closely.. The way it is currently would, I think, work if there was some hw that supported both cases (which is, I assume, why the gallium part of it works the way it does) </blockquote><div> </div><div>Yeah, I guess I could see that. In that case, I suppose you could just not run the pass? I guess you could have a case where HW supports both gl_FragCoords modes but only one pixel-center mode. Whatever. I guess I'm ok with 4 bools if it's useful. </div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> BR, -R <div class="HOEnZb"><div class="h5"> > Let's just make it two booleans. If we come across hardware that puts the > pixel center at 0.75, 0.25 then we can make fs_coord_pixel_center an enum. > --Jason > >> >> +} nir_lower_wpos_ytransform_options; >> + >> +bool nir_lower_wpos_ytransform(nir_shader *shader, >> + const nir_lower_wpos_ytransform_options >> *options); >> + >> void nir_lower_atomics(nir_shader *shader, >> const struct gl_shader_program *shader_program); >> void nir_lower_to_source_mods(nir_shader *shader); >> diff --git a/src/compiler/nir/nir_lower_wpos_ytransform.c >> b/src/compiler/nir/nir_lower_wpos_ytransform.c >> new file mode 100644 >> index 0000000..1d53530 >> --- /dev/null >> +++ b/src/compiler/nir/nir_lower_wpos_ytransform.c >> @@ -0,0 +1,310 @@ >> +/* >> + * Copyright © 2015 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. >> + */ >> + >> +#include "nir.h" >> +#include "nir_builder.h" >> + >> +/* Lower gl_FragCoord (and fddy) to account for driver's requested >> coordinate- >> + * origin and pixel-center vs. shader. If transformation is required, a >> + * gl_FbWposYTransform uniform is inserted (with the specified >> state-slots) >> + * and additional instructions are inserted to transform gl_FragCoord >> (and >> + * fddy src arg). >> + * >> + * This is based on the logic in emit_wpos()/emit_wpos_adjustment() in >> TGSI >> + * compiler. >> + * >> + * Run before nir_lower_io. >> + */ >> + >> +typedef struct { >> + const nir_lower_wpos_ytransform_options *options; >> + nir_shader *shader; >> + nir_builder b; >> + nir_variable *transform; >> +} lower_wpos_ytransform_state; >> + >> +static nir_ssa_def * >> +get_transform(lower_wpos_ytransform_state *state) >> +{ >> + if (state->transform == NULL) { >> + /* NOTE: name must be prefixed w/ "gl_" to trigger slot based >> + * special handling in uniform setup: >> + */ >> + nir_variable *var = nir_variable_create(state->shader, >> + nir_var_uniform, >> + glsl_vec4_type(), >> + "gl_FbWposYTransform"); >> + >> + var->num_state_slots = 1; >> + var->state_slots = ralloc_array(var, nir_state_slot, 1); >> + memcpy(var->state_slots[0].tokens, state->options->state_tokens, >> + sizeof(var->state_slots[0].tokens)); >> + >> + state->transform = var; >> + } >> + return nir_load_var(&state->b, state->transform); >> +} >> + >> +/* NIR equiv of TGSI CMP instruction: */ >> +static nir_ssa_def * >> +nir_cmp(nir_builder *b, nir_ssa_def *src0, nir_ssa_def *src1, nir_ssa_def >> *src2) >> +{ >> + return nir_bcsel(b, nir_flt(b, src0, nir_imm_float(b, 0.0)), src1, >> src2); >> +} >> + >> +/* see emit_wpos_adjustment() in st_mesa_to_tgsi.c */ >> +static void >> +emit_wpos_adjustment(lower_wpos_ytransform_state *state, >> + nir_intrinsic_instr *intr, >> + bool invert, float adjX, float adjY[2]) >> +{ >> + nir_builder *b = &state->b; >> + nir_variable *fragcoord = intr->variables[0]->var; >> + nir_ssa_def *wpostrans, *wpos_temp, *wpos_temp_y, *wpos_input; >> + >> + assert(intr->dest.is_ssa); >> + >> + b->cursor = nir_before_instr(&intr->instr); >> + >> + wpostrans = get_transform(state); >> + wpos_input = nir_load_var(b, fragcoord); >> + >> + /* First, apply the coordinate shift: */ >> + if (adjX || adjY[0] || adjY[1]) { >> + if (adjY[0] != adjY[1]) { >> + /* Adjust the y coordinate by adjY[1] or adjY[0] respectively >> + * depending on whether inversion is actually going to be >> applied >> + * or not, which is determined by testing against the inversion >> + * state variable used below, which will be either +1 or -1. >> + */ >> + nir_ssa_def *adj_temp; >> + >> + adj_temp = nir_cmp(b, >> + nir_channel(b, wpostrans, invert ? 2 : 0), >> + nir_imm_vec4(b, adjX, adjY[0], 0.0f, 0.0f), >> + nir_imm_vec4(b, adjX, adjY[1], 0.0f, 0.0f)); >> + >> + wpos_temp = nir_fadd(b, wpos_input, adj_temp); >> + } else { >> + wpos_temp = nir_fadd(b, >> + wpos_input, >> + nir_imm_vec4(b, adjX, adjY[0], 0.0f, >> 0.0f)); >> + } >> + wpos_input = wpos_temp; >> + } else { >> + /* MOV wpos_temp, input[wpos] >> + */ >> + wpos_temp = wpos_input; >> + } >> + >> + /* Now the conditional y flip: STATE_FB_WPOS_Y_TRANSFORM.xy/zw will be >> + * inversion/identity, or the other way around if we're drawing to an >> FBO. >> + */ >> + if (invert) { >> + /* MAD wpos_temp.y, wpos_input, wpostrans.xxxx, wpostrans.yyyy >> + */ >> + wpos_temp_y = nir_ffma(b, >> + nir_channel(b, wpos_temp, 1), >> + nir_channel(b, wpostrans, 0), >> + nir_channel(b, wpostrans, 1)); >> + } else { >> + /* MAD wpos_temp.y, wpos_input, wpostrans.zzzz, wpostrans.wwww >> + */ >> + wpos_temp_y = nir_ffma(b, >> + nir_channel(b, wpos_temp, 1), >> + nir_channel(b, wpostrans, 2), >> + nir_channel(b, wpostrans, 3)); >> + } >> + >> + wpos_temp = nir_vec4(b, >> + nir_channel(b, wpos_temp, 0), >> + wpos_temp_y, >> + nir_channel(b, wpos_temp, 2), >> + nir_channel(b, wpos_temp, 3)); >> + >> + nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(wpos_temp)); >> +} >> + >> +static void >> +lower_fragcoord(lower_wpos_ytransform_state *state, nir_intrinsic_instr >> *intr) >> +{ >> + const nir_lower_wpos_ytransform_options *options = state->options; >> + nir_variable *fragcoord = intr->variables[0]->var; >> + float adjX = 0.0f; >> + float adjY[2] = { 0.0f, 0.0f }; >> + bool invert = false; >> + >> + /* Based on logic in emit_wpos(): >> + * >> + * Query the pixel center conventions supported by the pipe driver and >> set >> + * adjX, adjY to help out if it cannot handle the requested one >> internally. >> + * >> + * The bias of the y-coordinate depends on whether y-inversion takes >> place >> + * (adjY[1]) or not (adjY[0]), which is in turn dependent on whether >> we are >> + * drawing to an FBO (causes additional inversion), and whether the >> the pipe >> + * driver origin and the requested origin differ (the latter condition >> is >> + * stored in the 'invert' variable). >> + * >> + * For height = 100 (i = integer, h = half-integer, l = lower, u = >> upper): >> + * >> + * center shift only: >> + * i -> h: +0.5 >> + * h -> i: -0.5 >> + * >> + * inversion only: >> + * l,i -> u,i: ( 0.0 + 1.0) * -1 + 100 = 99 >> + * l,h -> u,h: ( 0.5 + 0.0) * -1 + 100 = 99.5 >> + * u,i -> l,i: (99.0 + 1.0) * -1 + 100 = 0 >> + * u,h -> l,h: (99.5 + 0.0) * -1 + 100 = 0.5 >> + * >> + * inversion and center shift: >> + * l,i -> u,h: ( 0.0 + 0.5) * -1 + 100 = 99.5 >> + * l,h -> u,i: ( 0.5 + 0.5) * -1 + 100 = 99 >> + * u,i -> l,h: (99.0 + 0.5) * -1 + 100 = 0.5 >> + * u,h -> l,i: (99.5 + 0.5) * -1 + 100 = 0 >> + */ >> + >> + if (fragcoord->data.origin_upper_left) { >> + /* Fragment shader wants origin in upper-left */ >> + if (options->fs_coord_origin_upper_left) { >> + /* the driver supports upper-left origin */ >> + } else if (options->fs_coord_origin_lower_left) { >> + /* the driver supports lower-left origin, need to invert Y */ >> + invert = true; >> + } else { >> + unreachable("invalid options"); >> + } >> + } else { >> + /* Fragment shader wants origin in lower-left */ >> + if (options->fs_coord_origin_lower_left) { >> + /* the driver supports lower-left origin */ >> + } else if (options->fs_coord_origin_upper_left) { >> + /* the driver supports upper-left origin, need to invert Y */ >> + invert = true; >> + } else { >> + unreachable("invalid options"); >> + } >> + } >> + >> + if (fragcoord->data.pixel_center_integer) { >> + /* Fragment shader wants pixel center integer */ >> + if (options->fs_coord_pixel_center_integer) { >> + /* the driver supports pixel center integer */ >> + adjY[1] = 1.0f; >> + } else if (options->fs_coord_pixel_center_half_integer) { >> + /* the driver supports pixel center half integer, need to bias >> X,Y */ >> + adjX = -0.5f; >> + adjY[0] = -0.5f; >> + adjY[1] = 0.5f; >> + } else { >> + unreachable("invalid options"); >> + } >> + } else { >> + /* Fragment shader wants pixel center half integer */ >> + if (options->fs_coord_pixel_center_half_integer) { >> + /* the driver supports pixel center half integer */ >> + } else if (options->fs_coord_pixel_center_integer) { >> + /* the driver supports pixel center integer, need to bias X,Y */ >> + adjX = adjY[0] = adjY[1] = 0.5f; >> + } else { >> + unreachable("invalid options"); >> + } >> + } >> + >> + emit_wpos_adjustment(state, intr, invert, adjX, adjY); >> +} >> + >> +/* turns 'fddy(p)' into 'fddy(fmul(p, transform.x))' */ >> +static void >> +lower_fddy(lower_wpos_ytransform_state *state, nir_alu_instr *fddy) >> +{ >> + nir_builder *b = &state->b; >> + nir_ssa_def *p, *pt, *trans; >> + >> + b->cursor = nir_before_instr(&fddy->instr); >> + >> + p = nir_ssa_for_alu_src(b, fddy, 0); >> + trans = get_transform(state); >> + pt = nir_fmul(b, p, nir_channel(b, trans, 0)); >> + >> + nir_instr_rewrite_src(&fddy->instr, >> + &fddy->src[0].src, >> + nir_src_for_ssa(pt)); >> +} >> + >> +static bool >> +lower_wpos_ytransform_block(lower_wpos_ytransform_state *state, nir_block >> *block) >> +{ >> + nir_foreach_instr_safe(instr, block) { >> + if (instr->type == nir_instr_type_intrinsic) { >> + nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); >> + if (intr->intrinsic == nir_intrinsic_load_var) { >> + nir_deref_var *dvar = intr->variables[0]; >> + nir_variable *var = dvar->var; >> + >> + if (strcmp(var->name, "gl_FragCoord") == 0) { >> + /* gl_FragCoord should not have array/struct deref's: */ >> + assert(dvar->deref.child == NULL); >> + lower_fragcoord(state, intr); >> + } >> + } >> + } else if (instr->type == nir_instr_type_alu) { >> + nir_alu_instr *alu = nir_instr_as_alu(instr); >> + if (alu->op == nir_op_fddy) >> + lower_fddy(state, alu); >> + } >> + } >> + >> + return true; >> +} >> + >> +static void >> +lower_wpos_ytransform_impl(lower_wpos_ytransform_state *state, >> nir_function_impl *impl) >> +{ >> + nir_builder_init(&state->b, impl); >> + >> + nir_foreach_block(block, impl) { >> + lower_wpos_ytransform_block(state, block); >> + } >> + nir_metadata_preserve(impl, nir_metadata_block_index | >> + nir_metadata_dominance); >> +} >> + >> +bool >> +nir_lower_wpos_ytransform(nir_shader *shader, >> + const nir_lower_wpos_ytransform_options >> *options) >> +{ >> + lower_wpos_ytransform_state state = { >> + .options = options, >> + .shader = shader, >> + }; >> + >> + assert(shader->stage == MESA_SHADER_FRAGMENT); >> + >> + nir_foreach_function(function, shader) { >> + if (function->impl) >> + lower_wpos_ytransform_impl(&state, function->impl); >> + } >> + >> + return state.transform != NULL; >> +} >> -- >> 2.5.5 >> > </div></div></blockquote></div> </div></div>