--- /dev/null
+/*
+ * Copyright © 2023 Timothy Arceri <tarceri@itsqueeze.com>
+ * Copyright © 2016 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.
+ */
+
+
+#include "nir.h"
+#include "nir_builder.h"
+#include "gl_nir.h"
+#include "program/prog_instruction.h"
+
+#include "util/bitscan.h"
+#include "main/shader_types.h"
+
+#define imm1(b, x) nir_imm_float(b, x)
+#define imm3(b, x) nir_imm_vec3(b, x, x, x)
+
+static nir_ssa_def *
+swizzle(nir_builder *b, nir_ssa_def *src, int swizzle, int components)
+{
+ unsigned swizzle_arr[4];
+ swizzle_arr[0] = GET_SWZ(swizzle, 0);
+ swizzle_arr[1] = GET_SWZ(swizzle, 1);
+ swizzle_arr[2] = GET_SWZ(swizzle, 2);
+ swizzle_arr[3] = GET_SWZ(swizzle, 3);
+
+ return nir_swizzle(b, src, swizzle_arr, components);
+}
+
+static nir_ssa_def *
+swizzle_x(nir_builder *b, nir_ssa_def *src)
+{
+ return nir_channel(b, src, 0);
+}
+
+static nir_ssa_def *
+swizzle_y(nir_builder *b, nir_ssa_def *src)
+{
+ return nir_channel(b, src, 1);
+}
+
+static nir_ssa_def *
+swizzle_z(nir_builder *b, nir_ssa_def *src)
+{
+ return nir_channel(b, src, 2);
+}
+
+static nir_ssa_def *
+swizzle_w(nir_builder *b, nir_ssa_def *src)
+{
+ return nir_channel(b, src, 3);
+}
+
+static nir_ssa_def *
+blend_multiply(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = Cs*Cd */
+ return nir_fmul(b, src, dst);
+}
+
+static nir_ssa_def *
+blend_screen(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = Cs+Cd-Cs*Cd */
+ return nir_fsub(b, nir_fadd(b, src, dst), nir_fmul(b, src, dst));
+}
+
+static nir_ssa_def *
+blend_overlay(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = 2*Cs*Cd, if Cd <= 0.5
+ * 1-2*(1-Cs)*(1-Cd), otherwise
+ */
+ nir_ssa_def *rule_1 = nir_fmul(b, nir_fmul(b, src, dst), imm3(b, 2.0));
+ nir_ssa_def *rule_2 =
+ nir_fsub(b, imm3(b, 1.0), nir_fmul(b, nir_fmul(b, nir_fsub(b, imm3(b, 1.0), src), nir_fsub(b, imm3(b, 1.0), dst)), imm3(b, 2.0)));
+ return nir_bcsel(b, nir_fge(b, imm3(b, 0.5f), dst), rule_1, rule_2);
+}
+
+static nir_ssa_def *
+blend_darken(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = min(Cs,Cd) */
+ return nir_fmin(b, src, dst);
+}
+
+static nir_ssa_def *
+blend_lighten(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = max(Cs,Cd) */
+ return nir_fmax(b, src, dst);
+}
+
+static nir_ssa_def *
+blend_colordodge(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) =
+ * 0, if Cd <= 0
+ * min(1,Cd/(1-Cs)), if Cd > 0 and Cs < 1
+ * 1, if Cd > 0 and Cs >= 1
+ */
+ return nir_bcsel(b, nir_fge(b, imm3(b, 0.0), dst), imm3(b, 0.0),
+ nir_bcsel(b, nir_fge(b, src, imm3(b, 1.0)), imm3(b, 1.0),
+ nir_fmin(b, imm3(b, 1.0), nir_fdiv(b, dst, nir_fsub(b, imm3(b, 1.0), src)))));
+}
+
+static nir_ssa_def *
+blend_colorburn(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) =
+ * 1, if Cd >= 1
+ * 1 - min(1,(1-Cd)/Cs), if Cd < 1 and Cs > 0
+ * 0, if Cd < 1 and Cs <= 0
+ */
+ return nir_bcsel(b, nir_fge(b, dst, imm3(b, 1.0)), imm3(b, 1.0),
+ nir_bcsel(b, nir_fge(b, imm3(b, 0.0), src), imm3(b, 0.0),
+ nir_fsub(b, imm3(b, 1.0), nir_fmin(b, imm3(b, 1.0), nir_fdiv(b, nir_fsub(b, imm3(b, 1.0), dst), src)))));
+}
+
+static nir_ssa_def *
+blend_hardlight(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) = 2*Cs*Cd, if Cs <= 0.5
+ * 1-2*(1-Cs)*(1-Cd), otherwise
+ */
+ nir_ssa_def *rule_1 = nir_fmul(b, imm3(b, 2.0), nir_fmul(b, src, dst));
+ nir_ssa_def *rule_2 =
+ nir_fsub(b, imm3(b, 1.0), nir_fmul(b, imm3(b, 2.0), nir_fmul(b, nir_fsub(b, imm3(b, 1.0), src), nir_fsub(b, imm3(b, 1.0), dst))));
+ return nir_bcsel(b, nir_fge(b, imm3(b, 0.5), src), rule_1, rule_2);
+}
+
+static nir_ssa_def *
+blend_softlight(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ /* f(Cs,Cd) =
+ * Cd-(1-2*Cs)*Cd*(1-Cd),
+ * if Cs <= 0.5
+ * Cd+(2*Cs-1)*Cd*((16*Cd-12)*Cd+3),
+ * if Cs > 0.5 and Cd <= 0.25
+ * Cd+(2*Cs-1)*(sqrt(Cd)-Cd),
+ * if Cs > 0.5 and Cd > 0.25
+ *
+ * We can simplify this to
+ *
+ * f(Cs,Cd) = Cd+(2*Cs-1)*g(Cs,Cd) where
+ * g(Cs,Cd) = Cd*Cd-Cd if Cs <= 0.5
+ * Cd*((16*Cd-12)*Cd+3) if Cs > 0.5 and Cd <= 0.25
+ * sqrt(Cd)-Cd, otherwise
+ */
+ nir_ssa_def *factor_1 = nir_fmul(b, dst, nir_fsub(b, imm3(b, 1.0), dst));
+ nir_ssa_def *factor_2 =
+ nir_fmul(b, dst, nir_fadd(b, nir_fmul(b, nir_fsub(b, nir_fmul(b, imm3(b, 16.0), dst), imm3(b, 12.0)), dst), imm3(b, 3.0)));
+ nir_ssa_def *factor_3 = nir_fsub(b, nir_fsqrt(b, dst), dst);
+ nir_ssa_def *factor = nir_bcsel(b, nir_fge(b, imm3(b, 0.5), src), factor_1,
+ nir_bcsel(b, nir_fge(b, imm3(b, 0.25), dst), factor_2, factor_3));
+ return nir_fadd(b, dst, nir_fmul(b, nir_fsub(b, nir_fmul(b, imm3(b, 2.0), src), imm3(b, 1.0)), factor));
+}
+
+static nir_ssa_def *
+blend_difference(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ return nir_fabs(b, nir_fsub(b, dst, src));
+}
+
+static nir_ssa_def *
+blend_exclusion(nir_builder *b, nir_ssa_def *src, nir_ssa_def *dst)
+{
+ return nir_fadd(b, src, nir_fsub(b, dst, nir_fmul(b, imm3(b, 2.0), nir_fmul(b, src, dst))));
+}
+
+/* Return the minimum of a vec3's components */
+static nir_ssa_def *
+minv3(nir_builder *b, nir_ssa_def *v)
+{
+ return nir_fmin(b, nir_fmin(b, swizzle_x(b, v), swizzle_y(b, v)), swizzle_z(b, v));
+}
+
+/* Return the maximum of a vec3's components */
+static nir_ssa_def *
+maxv3(nir_builder *b, nir_ssa_def *v)
+{
+ return nir_fmax(b, nir_fmax(b, swizzle_x(b, v), swizzle_y(b, v)), swizzle_z(b, v));
+}
+
+static nir_ssa_def *
+lumv3(nir_builder *b, nir_ssa_def *c)
+{
+ return nir_fdot(b, c, nir_imm_vec3(b, 0.30, 0.59, 0.11));
+}
+
+static nir_ssa_def *
+satv3(nir_builder *b, nir_ssa_def *c)
+{
+ return nir_fsub(b, maxv3(b, c), minv3(b, c));
+}
+
+static nir_variable *
+add_temp_var(nir_builder *b, char *name, const struct glsl_type *type)
+{
+ nir_variable *var = rzalloc(b->shader, nir_variable);
+ var->type = type;
+ var->name = ralloc_strdup(var, name);
+ var->data.mode = nir_var_function_temp;
+ nir_function_impl_add_variable(b->impl, var);
+
+ return var;
+}
+
+/* Take the base RGB color <cbase> and override its luminosity with that
+ * of the RGB color <clum>.
+ *
+ * This follows the equations given in the ES 3.2 (June 15th, 2016)
+ * specification. Revision 16 of GL_KHR_blend_equation_advanced and
+ * revision 9 of GL_NV_blend_equation_advanced specify a different set
+ * of equations. Older revisions match ES 3.2's text, and dEQP expects
+ * the ES 3.2 rules implemented here.
+ */
+static void
+set_lum(nir_builder *b,
+ nir_variable *color,
+ nir_variable *cbase,
+ nir_variable *clum)
+{
+ nir_ssa_def *cbase_def = nir_load_var(b, cbase);
+ nir_store_var(b, color, nir_fadd(b, cbase_def, nir_fsub(b, lumv3(b, nir_load_var(b, clum)), lumv3(b, cbase_def))), ~0);
+
+ nir_variable *llum = add_temp_var(b, "__blend_lum", glsl_float_type());
+ nir_variable *mincol = add_temp_var(b, "__blend_mincol", glsl_float_type());
+ nir_variable *maxcol = add_temp_var(b, "__blend_maxcol", glsl_float_type());
+
+ nir_ssa_def *color_def = nir_load_var(b, color);
+ nir_store_var(b, llum, lumv3(b, color_def), ~0);
+ nir_store_var(b, mincol, minv3(b, color_def), ~0);
+ nir_store_var(b, maxcol, maxv3(b, color_def), ~0);
+
+ nir_ssa_def *mincol_def = nir_load_var(b, mincol);
+ nir_ssa_def *llum_def = nir_load_var(b, llum);
+ nir_if *nif = nir_push_if(b, nir_flt(b, mincol_def, imm1(b, 0.0)));
+
+ /* Add then block */
+ nir_store_var(b, color, nir_fadd(b, llum_def, nir_fdiv(b, nir_fmul(b, nir_fsub(b, color_def, llum_def), llum_def), nir_fsub(b, llum_def, mincol_def))), ~0);
+
+ /* Add else block */
+ nir_push_else(b, nif);
+ nir_ssa_def *maxcol_def = nir_load_var(b, maxcol);
+ nir_if *nif2 = nir_push_if(b, nir_flt(b, imm1(b, 1.0), maxcol_def));
+ nir_store_var(b, color, nir_fadd(b, llum_def, nir_fdiv(b, nir_fmul(b, nir_fsub(b, color_def, llum_def), nir_fsub(b, imm3(b, 1.0), llum_def)), nir_fsub(b, maxcol_def, llum_def))), ~0);
+ nir_pop_if(b, nif2);
+ nir_pop_if(b, nif);
+}
+
+/* Take the base RGB color <cbase> and override its saturation with
+ * that of the RGB color <csat>. The override the luminosity of the
+ * result with that of the RGB color <clum>.
+ */
+static void
+set_lum_sat(nir_builder *b,
+ nir_variable *color,
+ nir_variable *cbase,
+ nir_variable *csat,
+ nir_variable *clum)
+{
+ nir_ssa_def *cbase_def = nir_load_var(b, cbase);
+ nir_ssa_def *csat_def = nir_load_var(b, csat);
+
+ nir_variable *sbase = add_temp_var(b, "__blend_sbase", glsl_float_type());
+ nir_store_var(b, sbase, satv3(b, cbase_def), ~0);
+
+ /* Equivalent (modulo rounding errors) to setting the
+ * smallest (R,G,B) component to 0, the largest to <ssat>,
+ * and interpolating the "middle" component based on its
+ * original value relative to the smallest/largest.
+ */
+ nir_ssa_def *sbase_def = nir_load_var(b, sbase);
+ nir_if *nif = nir_push_if(b, nir_flt(b, imm1(b, 0.0), sbase_def));
+ nir_ssa_def *ssat = satv3(b, csat_def);
+ nir_ssa_def *minbase = minv3(b, cbase_def);
+ nir_store_var(b, color, nir_fdiv(b, nir_fmul(b, nir_fsub(b, cbase_def, minbase), ssat), sbase_def), ~0);
+ nir_push_else(b, nif);
+ nir_store_var(b, color, imm3(b, 0.0), ~0);
+ nir_pop_if(b, nif);
+
+ set_lum(b, color, color, clum);
+}
+
+static nir_ssa_def *
+is_mode(nir_builder *b, nir_variable *mode, enum gl_advanced_blend_mode q)
+{
+ return nir_ieq_imm(b, nir_load_var(b, mode), (unsigned) q);
+}
+
+static nir_variable *
+calc_blend_result(nir_builder *b,
+ nir_variable *mode,
+ nir_variable *fb,
+ nir_ssa_def *blend_src,
+ GLbitfield blend_qualifiers)
+{
+ nir_variable *result = add_temp_var(b, "__blend_result", glsl_vec4_type());
+
+ /* If we're not doing advanced blending, just write the original value. */
+ nir_if *if_blending = nir_push_if(b, is_mode(b, mode, BLEND_NONE));
+ nir_store_var(b, result, blend_src, ~0);
+
+ nir_push_else(b, if_blending);
+
+ /* (Rs', Gs', Bs') =
+ * (0, 0, 0), if As == 0
+ * (Rs/As, Gs/As, Bs/As), otherwise
+ */
+ nir_variable *src_rgb = add_temp_var(b, "__blend_src_rgb", glsl_vec_type(3));
+ nir_variable *src_alpha = add_temp_var(b, "__blend_src_a", glsl_float_type());
+
+ /* (Rd', Gd', Bd') =
+ * (0, 0, 0), if Ad == 0
+ * (Rd/Ad, Gd/Ad, Bd/Ad), otherwise
+ */
+ nir_variable *dst_rgb = add_temp_var(b, "__blend_dst_rgb", glsl_vec_type(3));
+ nir_variable *dst_alpha = add_temp_var(b, "__blend_dst_a", glsl_float_type());
+
+ nir_ssa_def *fb_def = nir_load_var(b, fb);
+ nir_store_var(b, dst_alpha, swizzle_w(b, fb_def), ~0);
+
+ nir_ssa_def *dst_alpha_def = nir_load_var(b, dst_alpha);
+ nir_if *nif = nir_push_if(b, nir_feq(b, dst_alpha_def, imm1(b, 0.0)));
+ nir_store_var(b, dst_rgb, imm3(b, 0.0), ~0);
+ nir_push_else(b, nif);
+ nir_store_var(b, dst_rgb, nir_bcsel(b, nir_feq(b, nir_trim_vector(b, fb_def, 3), swizzle(b, fb_def, SWIZZLE_WWWW, 3)), imm3(b, 1.0), nir_fdiv(b, nir_trim_vector(b, fb_def, 3), dst_alpha_def)), ~0);
+ nir_pop_if(b, nif);
+
+ nir_store_var(b, src_alpha, swizzle_w(b, blend_src), ~0);
+ nir_ssa_def *src_alpha_def = nir_load_var(b, src_alpha);
+ nif = nir_push_if(b, nir_feq(b, src_alpha_def, imm1(b, 0.0)));
+ nir_store_var(b, src_rgb, imm3(b, 0.0), ~0);
+ nir_push_else(b, nif);
+ nir_store_var(b, src_rgb, nir_bcsel(b, nir_feq(b, nir_trim_vector(b, blend_src, 3), swizzle(b, blend_src, SWIZZLE_WWWW, 3)), imm3(b, 1.0), nir_fdiv(b, nir_trim_vector(b, blend_src, 3), src_alpha_def)), ~0);
+ nir_pop_if(b, nif);
+
+ nir_variable *factor = add_temp_var(b, "__blend_factor", glsl_vec_type(3));
+
+ nir_ssa_def *src_rgb_def = nir_load_var(b, src_rgb);
+ nir_ssa_def *dst_rgb_def = nir_load_var(b, dst_rgb);
+
+ unsigned choices = blend_qualifiers;
+ while (choices) {
+ enum gl_advanced_blend_mode choice = (enum gl_advanced_blend_mode)u_bit_scan(&choices);
+
+ nir_if *iff = nir_push_if(b, is_mode(b, mode, choice));
+ nir_ssa_def *val = NULL;
+
+ switch (choice) {
+ case BLEND_MULTIPLY:
+ val = blend_multiply(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_SCREEN:
+ val = blend_screen(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_OVERLAY:
+ val = blend_overlay(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_DARKEN:
+ val = blend_darken(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_LIGHTEN:
+ val = blend_lighten(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_COLORDODGE:
+ val = blend_colordodge(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_COLORBURN:
+ val = blend_colorburn(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_HARDLIGHT:
+ val = blend_hardlight(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_SOFTLIGHT:
+ val = blend_softlight(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_DIFFERENCE:
+ val = blend_difference(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_EXCLUSION:
+ val = blend_exclusion(b, src_rgb_def, dst_rgb_def);
+ break;
+ case BLEND_HSL_HUE:
+ set_lum_sat(b, factor, src_rgb, dst_rgb, dst_rgb);
+ break;
+ case BLEND_HSL_SATURATION:
+ set_lum_sat(b, factor, dst_rgb, src_rgb, dst_rgb);
+ break;
+ case BLEND_HSL_COLOR:
+ set_lum(b, factor, src_rgb, dst_rgb);
+ break;
+ case BLEND_HSL_LUMINOSITY:
+ set_lum(b, factor, dst_rgb, src_rgb);
+ break;
+ case BLEND_NONE:
+ unreachable("not real cases");
+ }
+
+ if (val)
+ nir_store_var(b, factor, val, ~0);
+
+ nir_push_else(b, iff);
+ }
+
+ /* reset cursor to the outtermost if-statements else block */
+ b->cursor = nir_after_block(nir_if_last_else_block(if_blending));
+
+ /* p0(As,Ad) = As*Ad
+ * p1(As,Ad) = As*(1-Ad)
+ * p2(As,Ad) = Ad*(1-As)
+ */
+ nir_variable *p0 = add_temp_var(b, "__blend_p0", glsl_float_type());
+ nir_variable *p1 = add_temp_var(b, "__blend_p1", glsl_float_type());
+ nir_variable *p2 = add_temp_var(b, "__blend_p2", glsl_float_type());
+
+ nir_store_var(b, p0, nir_fmul(b, src_alpha_def, dst_alpha_def), ~0);
+ nir_store_var(b, p1, nir_fmul(b, src_alpha_def, nir_fsub(b, imm1(b, 1.0), dst_alpha_def)), ~0);
+ nir_store_var(b, p2, nir_fmul(b, dst_alpha_def, nir_fsub(b, imm1(b, 1.0), src_alpha_def)), ~0);
+
+ /* R = f(Rs',Rd')*p0(As,Ad) + Y*Rs'*p1(As,Ad) + Z*Rd'*p2(As,Ad)
+ * G = f(Gs',Gd')*p0(As,Ad) + Y*Gs'*p1(As,Ad) + Z*Gd'*p2(As,Ad)
+ * B = f(Bs',Bd')*p0(As,Ad) + Y*Bs'*p1(As,Ad) + Z*Bd'*p2(As,Ad)
+ * A = X*p0(As,Ad) + Y*p1(As,Ad) + Z*p2(As,Ad)
+ *
+ * <X, Y, Z> is always <1, 1, 1>, so we can ignore it.
+ *
+ * In vector form, this is:
+ * RGB = factor * p0 + Cs * p1 + Cd * p2
+ * A = p0 + p1 + p2
+ */
+ src_rgb_def = nir_load_var(b, src_rgb);
+ dst_rgb_def = nir_load_var(b, dst_rgb);
+ /* WRITEMASK_XYZ */
+ nir_store_var(b, result, nir_pad_vec4(b, nir_fadd(b, nir_fadd(b, nir_fmul(b, nir_load_var(b, factor), nir_load_var(b, p0)), nir_fmul(b, src_rgb_def, nir_load_var(b, p1))), nir_fmul(b, dst_rgb_def, nir_load_var(b, p2)))), 0x7);
+ /* WRITEMASK_W */
+ nir_ssa_def *val = nir_fadd(b, nir_fadd(b, nir_load_var(b, p0), nir_load_var(b, p1)), nir_load_var(b, p2));
+ nir_store_var(b, result, nir_vec4(b, val, val, val, val), 0x8);
+
+ /* reset cursor to the end of the main function */
+ b->cursor = nir_after_block(nir_impl_last_block(b->impl));
+
+ return result;
+}
+
+/**
+ * Dereference var, or var[0] if it's an array.
+ */
+static nir_ssa_def *
+load_output(nir_builder *b, nir_variable *var)
+{
+ nir_ssa_def *var_def;
+ if (glsl_type_is_array(var->type)) {
+ var_def = nir_load_array_var_imm(b, var, 0);
+ } else {
+ var_def = nir_load_var(b, var);
+ }
+
+ return var_def;
+}
+
+bool
+gl_nir_lower_blend_equation_advanced(nir_shader *sh, bool coherent)
+{
+ assert(sh->info.stage == MESA_SHADER_FRAGMENT);
+
+ /* All functions should have been inlined at this point */
+ assert(exec_list_length(&sh->functions) == 1);
+ nir_function_impl *impl = nir_shader_get_entrypoint(sh);
+
+ if (sh->info.fs.advanced_blend_modes == 0) {
+ nir_metadata_preserve(impl, nir_metadata_all);
+ return false;
+ }
+
+ sh->info.fs.uses_sample_shading = true;
+
+ nir_builder b;
+ nir_builder_init(&b, impl);
+ b.cursor = nir_after_block(nir_impl_last_block(impl));
+
+ nir_variable *fb = nir_variable_create(sh, nir_var_shader_out,
+ glsl_vec4_type(),
+ "__blend_fb_fetch");
+ fb->data.location = -1; /* We will set the location at the end of this pass */
+ fb->data.read_only = 1;
+ fb->data.fb_fetch_output = 1;
+ if (coherent)
+ fb->data.access = ACCESS_COHERENT;
+ fb->data.how_declared = nir_var_hidden;
+
+ nir_variable *mode = nir_variable_create(sh, nir_var_uniform,
+ glsl_uint_type(),
+ "gl_AdvancedBlendModeMESA");
+ mode->data.how_declared = nir_var_hidden;
+ mode->state_slots = rzalloc_array(mode, nir_state_slot, 1);
+ mode->num_state_slots = 1;
+ mode->state_slots[0].tokens[0] = STATE_ADVANCED_BLENDING_MODE;
+
+ /* Gather any output variables referring to render target 0.
+ *
+ * ARB_enhanced_layouts irritatingly allows the shader to specify
+ * multiple output variables for the same render target, each of
+ * which writes a subset of the components, starting at location_frac.
+ * The variables can't overlap, thankfully.
+ */
+ nir_variable *outputs[4] = { NULL, NULL, NULL, NULL };
+ nir_foreach_variable_with_modes(var, sh, nir_var_shader_out) {
+ if (var->data.location == FRAG_RESULT_DATA0 ||
+ var->data.location == FRAG_RESULT_COLOR) {
+ const int components =
+ glsl_get_vector_elements(glsl_without_array(var->type));
+
+ for (int i = 0; i < components; i++) {
+ if (outputs[var->data.location_frac + i] == NULL)
+ outputs[var->data.location_frac + i] = var;
+ }
+ }
+ }
+
+ /* Combine values written to outputs into a single RGBA blend source.
+ * We assign <0, 0, 0, 1> to any components with no corresponding output.
+ */
+ nir_ssa_def *blend_source;
+ if (outputs[0] &&
+ glsl_get_vector_elements(glsl_without_array(outputs[0]->type)) == 4) {
+ blend_source = load_output(&b, outputs[0]);
+ } else {
+ nir_ssa_def *blend_comps[4];
+ for (int i = 0; i < 4; i++) {
+ nir_variable *var = outputs[i];
+ if (var) {
+ blend_comps[i] = swizzle(&b, load_output(&b, outputs[i]),
+ i - outputs[i]->data.location_frac, 1);
+ } else {
+ blend_comps[i] = nir_imm_float(&b, i < 3 ? 0.0f : 1.0f);
+ }
+ }
+
+ blend_source = nir_vec(&b, blend_comps, 4);
+ }
+
+ nir_variable *result_dest =
+ calc_blend_result(&b, mode, fb, blend_source,
+ sh->info.fs.advanced_blend_modes);
+
+ /* Copy the result back to the original values. */
+ for (int i = 0; i < 4; i++) {
+ if (!outputs[i])
+ continue;
+
+ if (glsl_type_is_array(outputs[i]->type)) {
+ nir_store_array_var_imm(&b, outputs[i], 0, nir_load_var(&b, result_dest), 1 << i);
+ } else {
+ nir_ssa_def *val = swizzle(&b, nir_load_var(&b, result_dest), i, 1);
+ nir_store_var(&b, outputs[i], nir_vec4(&b, val, val, val, val), 1 << i);
+ }
+ }
+
+ nir_metadata_preserve(impl, nir_metadata_none);
+
+ /* Remove any dead writes before assigning location to __blend_fb_fetch
+ * otherwise they will be unable to be removed.
+ */
+ NIR_PASS_V(sh, nir_split_var_copies);
+ NIR_PASS_V(sh, nir_opt_dead_write_vars);
+
+ nir_foreach_variable_with_modes(var, sh, nir_var_shader_out) {
+ if (strcmp(var->name, "__blend_fb_fetch") == 0) {
+ var->data.location = FRAG_RESULT_DATA0;
+ break;
+ }
+ }
+
+ nir_validate_shader(sh, "after lower blend equation advanced");
+ return true;
+}
projects / platform / upstream / mesa.git / commitdiff