nir/algebraic: add option to lower fall_equalN/fany_nequalN
[mesa.git] / src / compiler / nir / nir_opt_algebraic.py
1 #
2 # Copyright (C) 2014 Intel Corporation
3 #
4 # Permission is hereby granted, free of charge, to any person obtaining a
5 # copy of this software and associated documentation files (the "Software"),
6 # to deal in the Software without restriction, including without limitation
7 # the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 # and/or sell copies of the Software, and to permit persons to whom the
9 # Software is furnished to do so, subject to the following conditions:
10 #
11 # The above copyright notice and this permission notice (including the next
12 # paragraph) shall be included in all copies or substantial portions of the
13 # Software.
14 #
15 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 # IN THE SOFTWARE.
22 #
23 # Authors:
24 # Jason Ekstrand (jason@jlekstrand.net)
25
26 from __future__ import print_function
27
28 from collections import OrderedDict
29 import nir_algebraic
30 from nir_opcodes import type_sizes
31 import itertools
32 from math import pi
33
34 # Convenience variables
35 a = 'a'
36 b = 'b'
37 c = 'c'
38 d = 'd'
39 e = 'e'
40
41 # Written in the form (<search>, <replace>) where <search> is an expression
42 # and <replace> is either an expression or a value. An expression is
43 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
44 # where each source is either an expression or a value. A value can be
45 # either a numeric constant or a string representing a variable name.
46 #
47 # If the opcode in a search expression is prefixed by a '~' character, this
48 # indicates that the operation is inexact. Such operations will only get
49 # applied to SSA values that do not have the exact bit set. This should be
50 # used by by any optimizations that are not bit-for-bit exact. It should not,
51 # however, be used for backend-requested lowering operations as those need to
52 # happen regardless of precision.
53 #
54 # Variable names are specified as "[#]name[@type][(cond)][.swiz]" where:
55 # "#" indicates that the given variable will only match constants,
56 # type indicates that the given variable will only match values from ALU
57 # instructions with the given output type,
58 # (cond) specifies an additional condition function (see nir_search_helpers.h),
59 # swiz is a swizzle applied to the variable (only in the <replace> expression)
60 #
61 # For constants, you have to be careful to make sure that it is the right
62 # type because python is unaware of the source and destination types of the
63 # opcodes.
64 #
65 # All expression types can have a bit-size specified. For opcodes, this
66 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
67 # type and size. In the search half of the expression this indicates that it
68 # should only match that particular bit-size. In the replace half of the
69 # expression this indicates that the constructed value should have that
70 # bit-size.
71 #
72 # A special condition "many-comm-expr" can be used with expressions to note
73 # that the expression and its subexpressions have more commutative expressions
74 # than nir_replace_instr can handle. If this special condition is needed with
75 # another condition, the two can be separated by a comma (e.g.,
76 # "(many-comm-expr,is_used_once)").
77
78 # based on https://web.archive.org/web/20180105155939/http://forum.devmaster.net/t/fast-and-accurate-sine-cosine/9648
79 def lowered_sincos(c):
80 x = ('fsub', ('fmul', 2.0, ('ffract', ('fadd', ('fmul', 0.5 / pi, a), c))), 1.0)
81 x = ('fmul', ('fsub', x, ('fmul', x, ('fabs', x))), 4.0)
82 return ('ffma', ('ffma', x, ('fabs', x), ('fneg', x)), 0.225, x)
83
84 optimizations = [
85
86 (('imul', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b)), '!options->lower_bitshift'),
87 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitshift'),
88 (('ishl', a, '#b@32'), ('imul', a, ('ishl', 1, b)), 'options->lower_bitshift'),
89
90 (('unpack_64_2x32_split_x', ('imul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
91 (('unpack_64_2x32_split_x', ('umul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
92 (('imul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('imul_high', a, b)), 'options->lower_mul_2x32_64'),
93 (('umul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('umul_high', a, b)), 'options->lower_mul_2x32_64'),
94 (('udiv', a, 1), a),
95 (('idiv', a, 1), a),
96 (('umod', a, 1), 0),
97 (('imod', a, 1), 0),
98 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b)), '!options->lower_bitshift'),
99 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
100 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
101 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
102
103 (('fneg', ('fneg', a)), a),
104 (('ineg', ('ineg', a)), a),
105 (('fabs', ('fabs', a)), ('fabs', a)),
106 (('fabs', ('fneg', a)), ('fabs', a)),
107 (('fabs', ('u2f', a)), ('u2f', a)),
108 (('iabs', ('iabs', a)), ('iabs', a)),
109 (('iabs', ('ineg', a)), ('iabs', a)),
110 (('f2b', ('fneg', a)), ('f2b', a)),
111 (('i2b', ('ineg', a)), ('i2b', a)),
112 (('~fadd', a, 0.0), a),
113 (('iadd', a, 0), a),
114 (('usadd_4x8', a, 0), a),
115 (('usadd_4x8', a, ~0), ~0),
116 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
117 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
118 (('~fadd', ('fneg', a), a), 0.0),
119 (('iadd', ('ineg', a), a), 0),
120 (('iadd', ('ineg', a), ('iadd', a, b)), b),
121 (('iadd', a, ('iadd', ('ineg', a), b)), b),
122 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
123 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
124 (('fadd', ('fsat', a), ('fsat', ('fneg', a))), ('fsat', ('fabs', a))),
125 (('~fmul', a, 0.0), 0.0),
126 (('imul', a, 0), 0),
127 (('umul_unorm_4x8', a, 0), 0),
128 (('umul_unorm_4x8', a, ~0), a),
129 (('fmul', a, 1.0), a),
130 (('imul', a, 1), a),
131 (('fmul', a, -1.0), ('fneg', a)),
132 (('imul', a, -1), ('ineg', a)),
133 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
134 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
135 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
136 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
137 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
138 (('~ffma', 0.0, a, b), b),
139 (('~ffma', a, b, 0.0), ('fmul', a, b)),
140 (('ffma', 1.0, a, b), ('fadd', a, b)),
141 (('ffma', -1.0, a, b), ('fadd', ('fneg', a), b)),
142 (('~flrp', a, b, 0.0), a),
143 (('~flrp', a, b, 1.0), b),
144 (('~flrp', a, a, b), a),
145 (('~flrp', 0.0, a, b), ('fmul', a, b)),
146
147 # flrp(a, a + b, c) => a + flrp(0, b, c) => a + (b * c)
148 (('~flrp', a, ('fadd(is_used_once)', a, b), c), ('fadd', ('fmul', b, c), a)),
149 (('~flrp@32', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp32'),
150 (('~flrp@64', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp64'),
151
152 (('~flrp@32', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp32'),
153 (('~flrp@64', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp64'),
154
155 (('~flrp@32', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp32'),
156 (('~flrp@64', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp64'),
157
158 (('~flrp', ('fmul(is_used_once)', a, b), ('fmul(is_used_once)', a, c), d), ('fmul', ('flrp', b, c, d), a)),
159
160 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
161 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
162 (('ftrunc', a), ('bcsel', ('flt', a, 0.0), ('fneg', ('ffloor', ('fabs', a))), ('ffloor', ('fabs', a))), 'options->lower_ftrunc'),
163 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
164 (('fadd', a, ('fneg', ('ffract', a))), ('ffloor', a), '!options->lower_ffloor'),
165 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
166 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
167 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
168 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
169 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
170 # These are the same as the previous three rules, but it depends on
171 # 1-fsat(x) <=> fsat(1-x). See below.
172 (('~fadd@32', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp32'),
173 (('~fadd@64', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp64'),
174
175 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
176 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
177 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
178 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
179 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
180
181 (('~fmul', ('fadd', ('iand', ('ineg', ('b2i32', 'a@bool')), ('fmul', b, c)), '#d'), '#e'),
182 ('bcsel', a, ('fmul', ('fadd', ('fmul', b, c), d), e), ('fmul', d, e))),
183
184 (('fdph', a, b), ('fdot4', ('vec4', 'a.x', 'a.y', 'a.z', 1.0), b), 'options->lower_fdph'),
185
186 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d), '!options->lower_fdph'),
187 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
188 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
189 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
190
191 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
192 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
193
194 (('fdot2', ('vec2', a, 0.0), b), ('fmul', a, b)),
195 (('fdot2', a, 1.0), ('fadd', 'a.x', 'a.y')),
196
197 # If x >= 0 and x <= 1: fsat(1 - x) == 1 - fsat(x) trivially
198 # If x < 0: 1 - fsat(x) => 1 - 0 => 1 and fsat(1 - x) => fsat(> 1) => 1
199 # If x > 1: 1 - fsat(x) => 1 - 1 => 0 and fsat(1 - x) => fsat(< 0) => 0
200 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
201
202 # 1 - ((1 - a) * (1 - b))
203 # 1 - (1 - a - b + a*b)
204 # 1 - 1 + a + b - a*b
205 # a + b - a*b
206 # a + b*(1 - a)
207 # b*(1 - a) + 1*a
208 # flrp(b, 1, a)
209 (('~fadd@32', 1.0, ('fneg', ('fmul', ('fadd', 1.0, ('fneg', a)), ('fadd', 1.0, ('fneg', b))))),
210 ('flrp', b, 1.0, a), '!options->lower_flrp32'),
211
212 # (a * #b + #c) << #d
213 # ((a * #b) << #d) + (#c << #d)
214 # (a * (#b << #d)) + (#c << #d)
215 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
216 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
217
218 # (a * #b) << #c
219 # a * (#b << #c)
220 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
221
222 # Comparison simplifications
223 (('~inot', ('flt', a, b)), ('fge', a, b)),
224 (('~inot', ('fge', a, b)), ('flt', a, b)),
225 (('inot', ('feq', a, b)), ('fne', a, b)),
226 (('inot', ('fne', a, b)), ('feq', a, b)),
227 (('inot', ('ilt', a, b)), ('ige', a, b)),
228 (('inot', ('ult', a, b)), ('uge', a, b)),
229 (('inot', ('ige', a, b)), ('ilt', a, b)),
230 (('inot', ('uge', a, b)), ('ult', a, b)),
231 (('inot', ('ieq', a, b)), ('ine', a, b)),
232 (('inot', ('ine', a, b)), ('ieq', a, b)),
233
234 (('iand', ('feq', a, b), ('fne', a, b)), False),
235 (('iand', ('flt', a, b), ('flt', b, a)), False),
236 (('iand', ('ieq', a, b), ('ine', a, b)), False),
237 (('iand', ('ilt', a, b), ('ilt', b, a)), False),
238 (('iand', ('ult', a, b), ('ult', b, a)), False),
239
240 # This helps some shaders because, after some optimizations, they end up
241 # with patterns like (-a < -b) || (b < a). In an ideal world, this sort of
242 # matching would be handled by CSE.
243 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
244 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
245 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
246 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
247 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
248 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
249 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
250 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
251 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
252 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
253
254 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
255 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
256 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
257 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
258 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
259 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
260
261 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
262 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
263 (('fge', 0.0, ('fsat(is_used_once)', a)), ('fge', 0.0, a)),
264 (('flt', 0.0, ('fsat(is_used_once)', a)), ('flt', 0.0, a)),
265
266 # 0.0 >= b2f(a)
267 # b2f(a) <= 0.0
268 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
269 # inot(a)
270 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
271
272 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
273
274 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
275 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
276 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
277 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
278 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
279 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
280 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
281 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
282 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
283 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
284 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
285 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
286 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
287 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
288 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
289 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
290 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
291 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
292 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
293 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
294
295 # -(b2f(a) + b2f(b)) < 0
296 # 0 < b2f(a) + b2f(b)
297 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
298 # a || b
299 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
300 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
301
302 # -(b2f(a) + b2f(b)) >= 0
303 # 0 >= b2f(a) + b2f(b)
304 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
305 # !(a || b)
306 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
307 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
308
309 (('flt', a, ('fneg', a)), ('flt', a, 0.0)),
310 (('fge', a, ('fneg', a)), ('fge', a, 0.0)),
311
312 # Some optimizations (below) convert things like (a < b || c < b) into
313 # (min(a, c) < b). However, this interfers with the previous optimizations
314 # that try to remove comparisons with negated sums of b2f. This just
315 # breaks that apart.
316 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
317 ('ior', ('flt', c, 0.0), ('ior', a, b))),
318
319 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
320 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
321 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
322 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
323
324 # Cannot remove the addition from ilt or ige due to overflow.
325 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
326 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
327
328 # fmin(-b2f(a), b) >= 0.0
329 # -b2f(a) >= 0.0 && b >= 0.0
330 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
331 # b2f(a) == 0.0 && b >= 0.0
332 # a == False && b >= 0.0
333 # !a && b >= 0.0
334 #
335 # The fge in the second replacement is not a typo. I leave the proof that
336 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
337 # reader.
338 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
339 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
340
341 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
342 (('fne', ('b2f', 'a@1'), 0.0), a),
343 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
344 (('ine', ('b2i', 'a@1'), 0), a),
345
346 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
347 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
348 (('fge', ('u2f', a), 0.0), True),
349 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
350 (('flt', ('u2f', a), 0.0), False),
351 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
352 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
353 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
354 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
355 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
356 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
357 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
358
359 # 0.0 < fabs(a)
360 # fabs(a) > 0.0
361 # fabs(a) != 0.0 because fabs(a) must be >= 0
362 # a != 0.0
363 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
364
365 # -fabs(a) < 0.0
366 # fabs(a) > 0.0
367 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
368
369 # 0.0 >= fabs(a)
370 # 0.0 == fabs(a) because fabs(a) must be >= 0
371 # 0.0 == a
372 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
373
374 # -fabs(a) >= 0.0
375 # 0.0 >= fabs(a)
376 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
377
378 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
379 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
380 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
381 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
382
383 # fmin(b2f(a), b)
384 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
385 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
386 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
387 #
388 # Since b is a constant, constant folding will eliminate the fmin and the
389 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
390 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
391
392 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
393
394 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
395 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
396 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
397 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
398 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
399 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
400 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
401 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
402 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
403 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
404 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
405 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
406 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
407 (('bcsel', a, True, b), ('ior', a, b)),
408 (('bcsel', a, a, b), ('ior', a, b)),
409 (('bcsel', a, b, False), ('iand', a, b)),
410 (('bcsel', a, b, a), ('iand', a, b)),
411 (('fmin', a, a), a),
412 (('fmax', a, a), a),
413 (('imin', a, a), a),
414 (('imax', a, a), a),
415 (('umin', a, a), a),
416 (('umax', a, a), a),
417 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
418 (('umax', ('umax', a, b), b), ('umax', a, b)),
419 (('imax', ('imax', a, b), b), ('imax', a, b)),
420 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
421 (('umin', ('umin', a, b), b), ('umin', a, b)),
422 (('imin', ('imin', a, b), b), ('imin', a, b)),
423 (('fmax', a, ('fneg', a)), ('fabs', a)),
424 (('imax', a, ('ineg', a)), ('iabs', a)),
425 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
426 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
427 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
428 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
429 (('fmin', a, ('fabs', a)), a),
430 (('imin', a, ('iabs', a)), a),
431 (('fmax', a, ('fneg', ('fabs', a))), a),
432 (('imax', a, ('ineg', ('iabs', a))), a),
433 (('fmax', a, ('fabs', a)), ('fabs', a)),
434 (('imax', a, ('iabs', a)), ('iabs', a)),
435 (('fmax', a, ('fneg', a)), ('fabs', a)),
436 (('imax', a, ('ineg', a)), ('iabs', a)),
437 (('~fmax', ('fabs', a), 0.0), ('fabs', a)),
438 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
439 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
440 (('~fmin', ('fmax', a, -1.0), 0.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
441 (('~fmax', ('fmin', a, 0.0), -1.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
442 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
443 (('fsat', ('b2f', a)), ('b2f', a)),
444 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
445 (('fsat', ('fsat', a)), ('fsat', a)),
446 (('fsat', ('fneg(is_used_once)', ('fadd(is_used_once)', a, b))), ('fsat', ('fadd', ('fneg', a), ('fneg', b))), '!options->lower_negate && !options->lower_fsat'),
447 (('fsat', ('fneg(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fneg', a), b)), '!options->lower_negate && !options->lower_fsat'),
448 (('fsat', ('fabs(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fabs', a), ('fabs', b))), '!options->lower_fsat'),
449 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
450 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
451 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
452 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
453 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
454 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
455 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
456 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
457 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
458 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
459 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
460 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
461 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
462 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
463 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
464 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
465 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
466 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
467 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
468 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
469 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
470 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
471
472 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
473 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
474 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
475 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
476 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
477 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
478 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
479 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
480 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
481 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
482 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
483 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
484 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
485 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
486 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
487 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
488
489 # Common pattern like 'if (i == 0 || i == 1 || ...)'
490 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
491 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
492 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
493
494 # The (i2f32, ...) part is an open-coded fsign. When that is combined with
495 # the bcsel, it's basically copysign(1.0, a). There is no copysign in NIR,
496 # so emit an open-coded version of that.
497 (('bcsel@32', ('feq', a, 0.0), 1.0, ('i2f32', ('iadd', ('b2i32', ('flt', 0.0, 'a@32')), ('ineg', ('b2i32', ('flt', 'a@32', 0.0)))))),
498 ('ior', 0x3f800000, ('iand', a, 0x80000000))),
499
500 (('ior', a, ('ieq', a, False)), True),
501 (('ior', a, ('inot', a)), -1),
502
503 (('ine', ('ineg', ('b2i32', 'a@1')), ('ineg', ('b2i32', 'b@1'))), ('ine', a, b)),
504 (('b2i32', ('ine', 'a@1', 'b@1')), ('b2i32', ('ixor', a, b))),
505
506 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
507
508 # These patterns can result when (a < b || a < c) => (a < min(b, c))
509 # transformations occur before constant propagation and loop-unrolling.
510 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
511 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
512 (('~fge', a, ('fmin', b, a)), True),
513 (('~fge', ('fmax', a, b), a), True),
514 (('~flt', a, ('fmin', b, a)), False),
515 (('~flt', ('fmax', a, b), a), False),
516 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
517 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
518
519 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
520 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
521 (('ige', a, ('imin', b, a)), True),
522 (('ige', ('imax', a, b), a), True),
523 (('ult', a, ('umax', b, a)), ('ult', a, b)),
524 (('ult', ('umin', a, b), a), ('ult', b, a)),
525 (('uge', a, ('umin', b, a)), True),
526 (('uge', ('umax', a, b), a), True),
527 (('ilt', a, ('imin', b, a)), False),
528 (('ilt', ('imax', a, b), a), False),
529 (('ige', a, ('imax', b, a)), ('ige', a, b)),
530 (('ige', ('imin', a, b), a), ('ige', b, a)),
531 (('ult', a, ('umin', b, a)), False),
532 (('ult', ('umax', a, b), a), False),
533 (('uge', a, ('umax', b, a)), ('uge', a, b)),
534 (('uge', ('umin', a, b), a), ('uge', b, a)),
535 (('ult', a, ('iand', b, a)), False),
536 (('ult', ('ior', a, b), a), False),
537 (('uge', a, ('iand', b, a)), True),
538 (('uge', ('ior', a, b), a), True),
539
540 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
541 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
542 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
543 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
544 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
545 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
546 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
547 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
548 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
549 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
550 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
551 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
552 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
553 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
554 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
555 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
556
557 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
558 # negative.
559 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
560 ('iabs', ('ishr', a, b))),
561 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
562
563 (('fabs', ('slt', a, b)), ('slt', a, b)),
564 (('fabs', ('sge', a, b)), ('sge', a, b)),
565 (('fabs', ('seq', a, b)), ('seq', a, b)),
566 (('fabs', ('sne', a, b)), ('sne', a, b)),
567 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
568 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
569 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
570 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
571 (('fall_equal2', a, b), ('fmin', ('seq', 'a.x', 'b.x'), ('seq', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
572 (('fall_equal3', a, b), ('seq', ('fany_nequal3', a, b), 0.0), 'options->lower_vector_cmp'),
573 (('fall_equal4', a, b), ('seq', ('fany_nequal4', a, b), 0.0), 'options->lower_vector_cmp'),
574 (('fany_nequal2', a, b), ('fmax', ('sne', 'a.x', 'b.x'), ('sne', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
575 (('fany_nequal3', a, b), ('fsat', ('fdot3', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
576 (('fany_nequal4', a, b), ('fsat', ('fdot4', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
577 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
578 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
579 # Emulating booleans
580 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
581 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
582 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
583 (('iand', 'a@bool32', 1.0), ('b2f', a)),
584 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
585 (('ineg', ('b2i32', 'a@32')), a),
586 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
587 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
588 # Comparison with the same args. Note that these are not done for
589 # the float versions because NaN always returns false on float
590 # inequalities.
591 (('ilt', a, a), False),
592 (('ige', a, a), True),
593 (('ieq', a, a), True),
594 (('ine', a, a), False),
595 (('ult', a, a), False),
596 (('uge', a, a), True),
597 # Logical and bit operations
598 (('iand', a, a), a),
599 (('iand', a, ~0), a),
600 (('iand', a, 0), 0),
601 (('ior', a, a), a),
602 (('ior', a, 0), a),
603 (('ior', a, True), True),
604 (('ixor', a, a), 0),
605 (('ixor', a, 0), a),
606 (('inot', ('inot', a)), a),
607 (('ior', ('iand', a, b), b), b),
608 (('ior', ('ior', a, b), b), ('ior', a, b)),
609 (('iand', ('ior', a, b), b), b),
610 (('iand', ('iand', a, b), b), ('iand', a, b)),
611 # DeMorgan's Laws
612 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
613 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
614 # Shift optimizations
615 (('ishl', 0, a), 0),
616 (('ishl', a, 0), a),
617 (('ishr', 0, a), 0),
618 (('ishr', a, 0), a),
619 (('ushr', 0, a), 0),
620 (('ushr', a, 0), a),
621 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
622 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
623 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('iadd', 16, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
624 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('isub', 16, b))), ('urol', a, b), '!options->lower_rotate'),
625 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('iadd', 32, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
626 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('isub', 32, b))), ('urol', a, b), '!options->lower_rotate'),
627 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('iadd', 16, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
628 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('isub', 16, b))), ('uror', a, b), '!options->lower_rotate'),
629 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('iadd', 32, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
630 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('isub', 32, b))), ('uror', a, b), '!options->lower_rotate'),
631 (('urol@16', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 16, b))), 'options->lower_rotate'),
632 (('urol@32', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 32, b))), 'options->lower_rotate'),
633 (('uror@16', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 16, b))), 'options->lower_rotate'),
634 (('uror@32', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 32, b))), 'options->lower_rotate'),
635 # Exponential/logarithmic identities
636 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
637 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
638 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
639 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
640 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
641 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
642 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
643 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
644 (('~fpow', a, 1.0), a),
645 (('~fpow', a, 2.0), ('fmul', a, a)),
646 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
647 (('~fpow', 2.0, a), ('fexp2', a)),
648 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
649 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
650 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
651 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
652 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
653 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
654 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
655 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
656 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
657 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
658 (('bcsel', ('flt', a, 0.0), 0.0, ('fsqrt', a)), ('fsqrt', ('fmax', a, 0.0))),
659 # Division and reciprocal
660 (('~fdiv', 1.0, a), ('frcp', a)),
661 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
662 (('~frcp', ('frcp', a)), a),
663 (('~frcp', ('fsqrt', a)), ('frsq', a)),
664 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
665 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
666 # Trig
667 (('fsin', a), lowered_sincos(0.5), 'options->lower_sincos'),
668 (('fcos', a), lowered_sincos(0.75), 'options->lower_sincos'),
669 # Boolean simplifications
670 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
671 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
672 (('ieq', a, True), a),
673 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
674 (('ine', a, False), a),
675 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
676 (('bcsel', a, True, False), a),
677 (('bcsel', a, False, True), ('inot', a)),
678 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
679 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
680 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
681 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
682 (('bcsel', True, b, c), b),
683 (('bcsel', False, b, c), c),
684 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
685
686 (('bcsel', a, b, b), b),
687 (('fcsel', a, b, b), b),
688
689 # D3D Boolean emulation
690 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
691 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
692 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
693 ('ineg', ('b2i', ('iand', a, b)))),
694 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
695 ('ineg', ('b2i', ('ior', a, b)))),
696 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
697 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
698 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
699 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
700 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
701
702 # SM5 32-bit shifts are defined to use the 5 least significant bits
703 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
704 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
705 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
706
707 # Conversions
708 (('i2b32', ('b2i', 'a@32')), a),
709 (('f2i', ('ftrunc', a)), ('f2i', a)),
710 (('f2u', ('ftrunc', a)), ('f2u', a)),
711 (('i2b', ('ineg', a)), ('i2b', a)),
712 (('i2b', ('iabs', a)), ('i2b', a)),
713 (('fabs', ('b2f', a)), ('b2f', a)),
714 (('iabs', ('b2i', a)), ('b2i', a)),
715 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
716
717 # Ironically, mark these as imprecise because removing the conversions may
718 # preserve more precision than doing the conversions (e.g.,
719 # uint(float(0x81818181u)) == 0x81818200).
720 (('~f2i32', ('i2f', 'a@32')), a),
721 (('~f2i32', ('u2f', 'a@32')), a),
722 (('~f2u32', ('i2f', 'a@32')), a),
723 (('~f2u32', ('u2f', 'a@32')), a),
724
725 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
726 # says:
727 #
728 # It is undefined to convert a negative floating-point value to an
729 # uint.
730 #
731 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
732 # some optimizations in the i965 backend to proceed.
733 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
734 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
735 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
736 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
737
738 (('~fmin', ('fabs', a), 1.0), ('fsat', ('fabs', a)), '!options->lower_fsat'),
739
740 # The result of the multiply must be in [-1, 0], so the result of the ffma
741 # must be in [0, 1].
742 (('flt', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), False),
743 (('flt', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), False),
744 (('fmax', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0)),
745 (('fmax', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0)),
746
747 # Packing and then unpacking does nothing
748 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
749 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
750 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
751 ('unpack_64_2x32_split_y', a)), a),
752
753 # Comparing two halves of an unpack separately. While this optimization
754 # should be correct for non-constant values, it's less obvious that it's
755 # useful in that case. For constant values, the pack will fold and we're
756 # guaranteed to reduce the whole tree to one instruction.
757 (('iand', ('ieq', ('unpack_32_2x16_split_x', a), '#b'),
758 ('ieq', ('unpack_32_2x16_split_y', a), '#c')),
759 ('ieq', a, ('pack_32_2x16_split', b, c))),
760
761 # Byte extraction
762 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
763 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
764 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
765 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
766 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
767 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
768 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
769 ]
770
771 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
772 # patterns like those below.
773 for op in ('ushr', 'ishr'):
774 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
775 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
776 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
777
778 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
779
780 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
781 # patterns like those below.
782 for op in ('extract_u8', 'extract_i8'):
783 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
784 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
785 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
786
787 optimizations.extend([
788 # Word extraction
789 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
790 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
791 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
792 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
793 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
794
795 # Subtracts
796 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
797 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
798 (('ussub_4x8', a, 0), a),
799 (('ussub_4x8', a, ~0), 0),
800 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
801 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
802 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
803 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
804 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
805 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
806 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
807 (('iabs', ('isub', 0, a)), ('iabs', a)),
808
809 # Propagate negation up multiplication chains
810 (('fmul(is_used_by_non_fsat)', ('fneg', a), b), ('fneg', ('fmul', a, b))),
811 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
812
813 # Propagate constants up multiplication chains
814 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
815 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
816 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
817 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
818
819 # Reassociate constants in add/mul chains so they can be folded together.
820 # For now, we mostly only handle cases where the constants are separated by
821 # a single non-constant. We could do better eventually.
822 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
823 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
824 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
825 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
826 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
827
828 # Drop mul-div by the same value when there's no wrapping.
829 (('idiv', ('imul(no_signed_wrap)', a, b), b), a),
830
831 # By definition...
832 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
833 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
834 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
835
836 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
837 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
838 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
839
840 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
841
842 # Misc. lowering
843 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
844 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
845 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
846 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
847 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
848
849 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
850 ('bcsel', ('ult', 31, 'bits'), 'insert',
851 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
852 'options->lower_bitfield_insert'),
853 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
854 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
855 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
856 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
857 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
858 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
859
860 # Alternative lowering that doesn't rely on bfi.
861 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
862 ('bcsel', ('ult', 31, 'bits'),
863 'insert',
864 (('ior',
865 ('iand', 'base', ('inot', ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))),
866 ('iand', ('ishl', 'insert', 'offset'), ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))))),
867 'options->lower_bitfield_insert_to_shifts'),
868
869 # Alternative lowering that uses bitfield_select.
870 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
871 ('bcsel', ('ult', 31, 'bits'), 'insert',
872 ('bitfield_select', ('bfm', 'bits', 'offset'), ('ishl', 'insert', 'offset'), 'base')),
873 'options->lower_bitfield_insert_to_bitfield_select'),
874
875 (('ibitfield_extract', 'value', 'offset', 'bits'),
876 ('bcsel', ('ult', 31, 'bits'), 'value',
877 ('ibfe', 'value', 'offset', 'bits')),
878 'options->lower_bitfield_extract'),
879
880 (('ubitfield_extract', 'value', 'offset', 'bits'),
881 ('bcsel', ('ult', 31, 'bits'), 'value',
882 ('ubfe', 'value', 'offset', 'bits')),
883 'options->lower_bitfield_extract'),
884
885 # Note that these opcodes are defined to only use the five least significant bits of 'offset' and 'bits'
886 (('ubfe', 'value', 'offset', ('iand', 31, 'bits')), ('ubfe', 'value', 'offset', 'bits')),
887 (('ubfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ubfe', 'value', 'offset', 'bits')),
888 (('ibfe', 'value', 'offset', ('iand', 31, 'bits')), ('ibfe', 'value', 'offset', 'bits')),
889 (('ibfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ibfe', 'value', 'offset', 'bits')),
890 (('bfm', 'bits', ('iand', 31, 'offset')), ('bfm', 'bits', 'offset')),
891 (('bfm', ('iand', 31, 'bits'), 'offset'), ('bfm', 'bits', 'offset')),
892
893 (('ibitfield_extract', 'value', 'offset', 'bits'),
894 ('bcsel', ('ieq', 0, 'bits'),
895 0,
896 ('ishr',
897 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
898 ('isub', 32, 'bits'))),
899 'options->lower_bitfield_extract_to_shifts'),
900
901 (('ubitfield_extract', 'value', 'offset', 'bits'),
902 ('iand',
903 ('ushr', 'value', 'offset'),
904 ('bcsel', ('ieq', 'bits', 32),
905 0xffffffff,
906 ('isub', ('ishl', 1, 'bits'), 1))),
907 'options->lower_bitfield_extract_to_shifts'),
908
909 (('ifind_msb', 'value'),
910 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
911 'options->lower_ifind_msb'),
912
913 (('find_lsb', 'value'),
914 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
915 'options->lower_find_lsb'),
916
917 (('extract_i8', a, 'b@32'),
918 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
919 'options->lower_extract_byte'),
920
921 (('extract_u8', a, 'b@32'),
922 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
923 'options->lower_extract_byte'),
924
925 (('extract_i16', a, 'b@32'),
926 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
927 'options->lower_extract_word'),
928
929 (('extract_u16', a, 'b@32'),
930 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
931 'options->lower_extract_word'),
932
933 (('pack_unorm_2x16', 'v'),
934 ('pack_uvec2_to_uint',
935 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
936 'options->lower_pack_unorm_2x16'),
937
938 (('pack_unorm_4x8', 'v'),
939 ('pack_uvec4_to_uint',
940 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
941 'options->lower_pack_unorm_4x8'),
942
943 (('pack_snorm_2x16', 'v'),
944 ('pack_uvec2_to_uint',
945 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
946 'options->lower_pack_snorm_2x16'),
947
948 (('pack_snorm_4x8', 'v'),
949 ('pack_uvec4_to_uint',
950 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
951 'options->lower_pack_snorm_4x8'),
952
953 (('unpack_unorm_2x16', 'v'),
954 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
955 ('extract_u16', 'v', 1))),
956 65535.0),
957 'options->lower_unpack_unorm_2x16'),
958
959 (('unpack_unorm_4x8', 'v'),
960 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
961 ('extract_u8', 'v', 1),
962 ('extract_u8', 'v', 2),
963 ('extract_u8', 'v', 3))),
964 255.0),
965 'options->lower_unpack_unorm_4x8'),
966
967 (('unpack_snorm_2x16', 'v'),
968 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
969 ('extract_i16', 'v', 1))),
970 32767.0))),
971 'options->lower_unpack_snorm_2x16'),
972
973 (('unpack_snorm_4x8', 'v'),
974 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
975 ('extract_i8', 'v', 1),
976 ('extract_i8', 'v', 2),
977 ('extract_i8', 'v', 3))),
978 127.0))),
979 'options->lower_unpack_snorm_4x8'),
980
981 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
982 (('fsign', a), ('fsub', ('b2f', ('flt', 0.0, a)), ('b2f', ('flt', a, 0.0))), 'options->lower_fsign'),
983 ])
984
985 # bit_size dependent lowerings
986 for bit_size in [8, 16, 32, 64]:
987 # convenience constants
988 intmax = (1 << (bit_size - 1)) - 1
989 intmin = 1 << (bit_size - 1)
990
991 optimizations += [
992 (('iadd_sat@' + str(bit_size), a, b),
993 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
994 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
995 (('isub_sat@' + str(bit_size), a, b),
996 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
997 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
998 ]
999
1000 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
1001
1002 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
1003 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
1004 ('iand', (invert[left], a, b), (invert[right], c, d))))
1005 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
1006 ('ior', (invert[left], a, b), (invert[right], c, d))))
1007
1008 # Optimize x2bN(b2x(x)) -> x
1009 for size in type_sizes('bool'):
1010 aN = 'a@' + str(size)
1011 f2bN = 'f2b' + str(size)
1012 i2bN = 'i2b' + str(size)
1013 optimizations.append(((f2bN, ('b2f', aN)), a))
1014 optimizations.append(((i2bN, ('b2i', aN)), a))
1015
1016 # Optimize x2yN(b2x(x)) -> b2y
1017 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
1018 if x != 'f' and y != 'f' and x != y:
1019 continue
1020
1021 b2x = 'b2f' if x == 'f' else 'b2i'
1022 b2y = 'b2f' if y == 'f' else 'b2i'
1023 x2yN = '{}2{}'.format(x, y)
1024 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
1025
1026 # Optimize away x2xN(a@N)
1027 for t in ['int', 'uint', 'float']:
1028 for N in type_sizes(t):
1029 x2xN = '{0}2{0}{1}'.format(t[0], N)
1030 aN = 'a@{0}'.format(N)
1031 optimizations.append(((x2xN, aN), a))
1032
1033 # Optimize x2xN(y2yM(a@P)) -> y2yN(a) for integers
1034 # In particular, we can optimize away everything except upcast of downcast and
1035 # upcasts where the type differs from the other cast
1036 for N, M in itertools.product(type_sizes('uint'), type_sizes('uint')):
1037 if N < M:
1038 # The outer cast is a down-cast. It doesn't matter what the size of the
1039 # argument of the inner cast is because we'll never been in the upcast
1040 # of downcast case. Regardless of types, we'll always end up with y2yN
1041 # in the end.
1042 for x, y in itertools.product(['i', 'u'], ['i', 'u']):
1043 x2xN = '{0}2{0}{1}'.format(x, N)
1044 y2yM = '{0}2{0}{1}'.format(y, M)
1045 y2yN = '{0}2{0}{1}'.format(y, N)
1046 optimizations.append(((x2xN, (y2yM, a)), (y2yN, a)))
1047 elif N > M:
1048 # If the outer cast is an up-cast, we have to be more careful about the
1049 # size of the argument of the inner cast and with types. In this case,
1050 # the type is always the type of type up-cast which is given by the
1051 # outer cast.
1052 for P in type_sizes('uint'):
1053 # We can't optimize away up-cast of down-cast.
1054 if M < P:
1055 continue
1056
1057 # Because we're doing down-cast of down-cast, the types always have
1058 # to match between the two casts
1059 for x in ['i', 'u']:
1060 x2xN = '{0}2{0}{1}'.format(x, N)
1061 x2xM = '{0}2{0}{1}'.format(x, M)
1062 aP = 'a@{0}'.format(P)
1063 optimizations.append(((x2xN, (x2xM, aP)), (x2xN, a)))
1064 else:
1065 # The N == M case is handled by other optimizations
1066 pass
1067
1068 # Optimize comparisons with up-casts
1069 for t in ['int', 'uint', 'float']:
1070 for N, M in itertools.product(type_sizes(t), repeat=2):
1071 if N == 1 or N >= M:
1072 continue
1073
1074 x2xM = '{0}2{0}{1}'.format(t[0], M)
1075 x2xN = '{0}2{0}{1}'.format(t[0], N)
1076 aN = 'a@' + str(N)
1077 bN = 'b@' + str(N)
1078 xeq = 'feq' if t == 'float' else 'ieq'
1079 xne = 'fne' if t == 'float' else 'ine'
1080 xge = '{0}ge'.format(t[0])
1081 xlt = '{0}lt'.format(t[0])
1082
1083 # Up-casts are lossless so for correctly signed comparisons of
1084 # up-casted values we can do the comparison at the largest of the two
1085 # original sizes and drop one or both of the casts. (We have
1086 # optimizations to drop the no-op casts which this may generate.)
1087 for P in type_sizes(t):
1088 if P == 1 or P > N:
1089 continue
1090
1091 bP = 'b@' + str(P)
1092 optimizations += [
1093 ((xeq, (x2xM, aN), (x2xM, bP)), (xeq, a, (x2xN, b))),
1094 ((xne, (x2xM, aN), (x2xM, bP)), (xne, a, (x2xN, b))),
1095 ((xge, (x2xM, aN), (x2xM, bP)), (xge, a, (x2xN, b))),
1096 ((xlt, (x2xM, aN), (x2xM, bP)), (xlt, a, (x2xN, b))),
1097 ((xge, (x2xM, bP), (x2xM, aN)), (xge, (x2xN, b), a)),
1098 ((xlt, (x2xM, bP), (x2xM, aN)), (xlt, (x2xN, b), a)),
1099 ]
1100
1101 # The next bit doesn't work on floats because the range checks would
1102 # get way too complicated.
1103 if t in ['int', 'uint']:
1104 if t == 'int':
1105 xN_min = -(1 << (N - 1))
1106 xN_max = (1 << (N - 1)) - 1
1107 elif t == 'uint':
1108 xN_min = 0
1109 xN_max = (1 << N) - 1
1110 else:
1111 assert False
1112
1113 # If we're up-casting and comparing to a constant, we can unfold
1114 # the comparison into a comparison with the shrunk down constant
1115 # and a check that the constant fits in the smaller bit size.
1116 optimizations += [
1117 ((xeq, (x2xM, aN), '#b'),
1118 ('iand', (xeq, a, (x2xN, b)), (xeq, (x2xM, (x2xN, b)), b))),
1119 ((xne, (x2xM, aN), '#b'),
1120 ('ior', (xne, a, (x2xN, b)), (xne, (x2xM, (x2xN, b)), b))),
1121 ((xlt, (x2xM, aN), '#b'),
1122 ('iand', (xlt, xN_min, b),
1123 ('ior', (xlt, xN_max, b), (xlt, a, (x2xN, b))))),
1124 ((xlt, '#a', (x2xM, bN)),
1125 ('iand', (xlt, a, xN_max),
1126 ('ior', (xlt, a, xN_min), (xlt, (x2xN, a), b)))),
1127 ((xge, (x2xM, aN), '#b'),
1128 ('iand', (xge, xN_max, b),
1129 ('ior', (xge, xN_min, b), (xge, a, (x2xN, b))))),
1130 ((xge, '#a', (x2xM, bN)),
1131 ('iand', (xge, a, xN_min),
1132 ('ior', (xge, a, xN_max), (xge, (x2xN, a), b)))),
1133 ]
1134
1135 def fexp2i(exp, bits):
1136 # We assume that exp is already in the right range.
1137 if bits == 16:
1138 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
1139 elif bits == 32:
1140 return ('ishl', ('iadd', exp, 127), 23)
1141 elif bits == 64:
1142 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
1143 else:
1144 assert False
1145
1146 def ldexp(f, exp, bits):
1147 # First, we clamp exp to a reasonable range. The maximum possible range
1148 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
1149 # a maximum range of [-149, 127]. This means that we can potentially have
1150 # a swing of +-276. If you start with FLT_MAX, you actually have to do
1151 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
1152 # spec, on the other hand, only requires that we handle an exponent value
1153 # in the range [-126, 128]. This implementation is *mostly* correct; it
1154 # handles a range on exp of [-252, 254] which allows you to create any
1155 # value (including denorms if the hardware supports it) and to adjust the
1156 # exponent of any normal value to anything you want.
1157 if bits == 16:
1158 exp = ('imin', ('imax', exp, -28), 30)
1159 elif bits == 32:
1160 exp = ('imin', ('imax', exp, -252), 254)
1161 elif bits == 64:
1162 exp = ('imin', ('imax', exp, -2044), 2046)
1163 else:
1164 assert False
1165
1166 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
1167 # (We use ishr which isn't the same for -1, but the -1 case still works
1168 # since we use exp-exp/2 as the second exponent.) While the spec
1169 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
1170 # work with denormals and doesn't allow for the full swing in exponents
1171 # that you can get with normalized values. Instead, we create two powers
1172 # of two and multiply by them each in turn. That way the effective range
1173 # of our exponent is doubled.
1174 pow2_1 = fexp2i(('ishr', exp, 1), bits)
1175 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
1176 return ('fmul', ('fmul', f, pow2_1), pow2_2)
1177
1178 optimizations += [
1179 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
1180 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
1181 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
1182 ]
1183
1184 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
1185 def bitfield_reverse(u):
1186 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
1187 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
1188 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
1189 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
1190 step5 = ('ior(many-comm-expr)', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
1191
1192 return step5
1193
1194 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
1195
1196 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
1197 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
1198 # and, if a is a NaN then the second comparison will fail anyway.
1199 for op in ['flt', 'fge', 'feq']:
1200 optimizations += [
1201 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
1202 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
1203 ]
1204
1205 # Add optimizations to handle the case where the result of a ternary is
1206 # compared to a constant. This way we can take things like
1207 #
1208 # (a ? 0 : 1) > 0
1209 #
1210 # and turn it into
1211 #
1212 # a ? (0 > 0) : (1 > 0)
1213 #
1214 # which constant folding will eat for lunch. The resulting ternary will
1215 # further get cleaned up by the boolean reductions above and we will be
1216 # left with just the original variable "a".
1217 for op in ['flt', 'fge', 'feq', 'fne',
1218 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
1219 optimizations += [
1220 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
1221 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
1222 ((op, '#d', ('bcsel', a, '#b', '#c')),
1223 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
1224 ]
1225
1226
1227 # For example, this converts things like
1228 #
1229 # 1 + mix(0, a - 1, condition)
1230 #
1231 # into
1232 #
1233 # mix(1, (a-1)+1, condition)
1234 #
1235 # Other optimizations will rearrange the constants.
1236 for op in ['fadd', 'fmul', 'iadd', 'imul']:
1237 optimizations += [
1238 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
1239 ]
1240
1241 # For derivatives in compute shaders, GLSL_NV_compute_shader_derivatives
1242 # states:
1243 #
1244 # If neither layout qualifier is specified, derivatives in compute shaders
1245 # return zero, which is consistent with the handling of built-in texture
1246 # functions like texture() in GLSL 4.50 compute shaders.
1247 for op in ['fddx', 'fddx_fine', 'fddx_coarse',
1248 'fddy', 'fddy_fine', 'fddy_coarse']:
1249 optimizations += [
1250 ((op, 'a'), 0.0, 'info->stage == MESA_SHADER_COMPUTE && info->cs.derivative_group == DERIVATIVE_GROUP_NONE')
1251 ]
1252
1253 # Some optimizations for ir3-specific instructions.
1254 optimizations += [
1255 # 'al * bl': If either 'al' or 'bl' is zero, return zero.
1256 (('umul_low', '#a(is_lower_half_zero)', 'b'), (0)),
1257 # '(ah * bl) << 16 + c': If either 'ah' or 'bl' is zero, return 'c'.
1258 (('imadsh_mix16', '#a@32(is_lower_half_zero)', 'b@32', 'c@32'), ('c')),
1259 (('imadsh_mix16', 'a@32', '#b@32(is_upper_half_zero)', 'c@32'), ('c')),
1260 ]
1261
1262 # This section contains "late" optimizations that should be run before
1263 # creating ffmas and calling regular optimizations for the final time.
1264 # Optimizations should go here if they help code generation and conflict
1265 # with the regular optimizations.
1266 before_ffma_optimizations = [
1267 # Propagate constants down multiplication chains
1268 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
1269 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
1270 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
1271 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
1272
1273 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
1274 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
1275 (('~fadd', ('fneg', a), a), 0.0),
1276 (('iadd', ('ineg', a), a), 0),
1277 (('iadd', ('ineg', a), ('iadd', a, b)), b),
1278 (('iadd', a, ('iadd', ('ineg', a), b)), b),
1279 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
1280 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
1281
1282 (('~flrp@32', ('fadd(is_used_once)', a, -1.0), ('fadd(is_used_once)', a, 1.0), d), ('fadd', ('flrp', -1.0, 1.0, d), a)),
1283 (('~flrp@32', ('fadd(is_used_once)', a, 1.0), ('fadd(is_used_once)', a, -1.0), d), ('fadd', ('flrp', 1.0, -1.0, d), a)),
1284 (('~flrp@32', ('fadd(is_used_once)', a, '#b'), ('fadd(is_used_once)', a, '#c'), d), ('fadd', ('fmul', d, ('fadd', c, ('fneg', b))), ('fadd', a, b))),
1285 ]
1286
1287 # This section contains "late" optimizations that should be run after the
1288 # regular optimizations have finished. Optimizations should go here if
1289 # they help code generation but do not necessarily produce code that is
1290 # more easily optimizable.
1291 late_optimizations = [
1292 # Most of these optimizations aren't quite safe when you get infinity or
1293 # Nan involved but the first one should be fine.
1294 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1295 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1296 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1297 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1298 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1299 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1300
1301 # nir_lower_to_source_mods will collapse this, but its existence during the
1302 # optimization loop can prevent other optimizations.
1303 (('fneg', ('fneg', a)), a),
1304
1305 # These are duplicated from the main optimizations table. The late
1306 # patterns that rearrange expressions like x - .5 < 0 to x < .5 can create
1307 # new patterns like these. The patterns that compare with zero are removed
1308 # because they are unlikely to be created in by anything in
1309 # late_optimizations.
1310 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
1311 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
1312 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
1313 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
1314 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
1315 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
1316
1317 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
1318 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
1319
1320 (('~fge', ('fmin(is_used_once)', ('fadd(is_used_once)', a, b), ('fadd', c, d)), 0.0), ('iand', ('fge', a, ('fneg', b)), ('fge', c, ('fneg', d)))),
1321
1322 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
1323 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
1324 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
1325 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
1326 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
1327 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
1328 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
1329 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
1330 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
1331 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
1332
1333 (('ior', a, a), a),
1334 (('iand', a, a), a),
1335
1336 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
1337
1338 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1339 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1340 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1341 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1342
1343 (('~flrp@32', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1344 (('~flrp@64', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1345
1346 (('~fadd@32', 1.0, ('fmul(is_used_once)', c , ('fadd', b, -1.0 ))), ('fadd', ('fadd', 1.0, ('fneg', c)), ('fmul', b, c)), 'options->lower_flrp32'),
1347 (('~fadd@64', 1.0, ('fmul(is_used_once)', c , ('fadd', b, -1.0 ))), ('fadd', ('fadd', 1.0, ('fneg', c)), ('fmul', b, c)), 'options->lower_flrp64'),
1348
1349 # A similar operation could apply to any ffma(#a, b, #(-a/2)), but this
1350 # particular operation is common for expanding values stored in a texture
1351 # from [0,1] to [-1,1].
1352 (('~ffma@32', a, 2.0, -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1353 (('~ffma@32', a, -2.0, -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1354 (('~ffma@32', a, -2.0, 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1355 (('~ffma@32', a, 2.0, 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1356 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1357 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1358 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1359 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1360
1361 # flrp(a, b, a)
1362 # a*(1-a) + b*a
1363 # a + -a*a + a*b (1)
1364 # a + a*(b - a)
1365 # Option 1: ffma(a, (b-a), a)
1366 #
1367 # Alternately, after (1):
1368 # a*(1+b) + -a*a
1369 # a*((1+b) + -a)
1370 #
1371 # Let b=1
1372 #
1373 # Option 2: ffma(a, 2, -(a*a))
1374 # Option 3: ffma(a, 2, (-a)*a)
1375 # Option 4: ffma(a, -a, (2*a)
1376 # Option 5: a * (2 - a)
1377 #
1378 # There are a lot of other possible combinations.
1379 (('~ffma@32', ('fadd', b, ('fneg', a)), a, a), ('flrp', a, b, a), '!options->lower_flrp32'),
1380 (('~ffma@32', a, 2.0, ('fneg', ('fmul', a, a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1381 (('~ffma@32', a, 2.0, ('fmul', ('fneg', a), a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1382 (('~ffma@32', a, ('fneg', a), ('fmul', 2.0, a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1383 (('~fmul@32', a, ('fadd', 2.0, ('fneg', a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1384
1385 # we do these late so that we don't get in the way of creating ffmas
1386 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1387 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1388
1389 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1390
1391 # Things that look like DPH in the source shader may get expanded to
1392 # something that looks like dot(v1.xyz, v2.xyz) + v1.w by the time it gets
1393 # to NIR. After FFMA is generated, this can look like:
1394 #
1395 # fadd(ffma(v1.z, v2.z, ffma(v1.y, v2.y, fmul(v1.x, v2.x))), v1.w)
1396 #
1397 # Reassociate the last addition into the first multiplication.
1398 (('~fadd', ('ffma(is_used_once)', a, b, ('ffma', c, d, ('fmul', 'e(is_not_const_and_not_fsign)', 'f(is_not_const_and_not_fsign)'))), 'g(is_not_const)'),
1399 ('ffma', a, b, ('ffma', c, d, ('ffma', e, 'f', 'g'))), '!options->intel_vec4'),
1400 (('~fadd', ('ffma(is_used_once)', a, b, ('fmul', 'e(is_not_const_and_not_fsign)', 'f(is_not_const_and_not_fsign)') ), 'g(is_not_const)'),
1401 ('ffma', a, b, ('ffma', e, 'f', 'g') ), '!options->intel_vec4'),
1402 ]
1403
1404 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1405 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1406 before_ffma_optimizations).render())
1407 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1408 late_optimizations).render())