nir/algebraic: Replace checks that a value is between (or not) [0, 1]
[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_bitops'),
87 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitops'),
88 (('ishl', a, '#b@32'), ('imul', a, ('ishl', 1, b)), 'options->lower_bitops'),
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_bitops'),
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 # Lower fdot to fsum when it is available
198 (('fdot2', a, b), ('fsum2', ('fmul', a, b)), 'options->lower_fdot'),
199 (('fdot3', a, b), ('fsum3', ('fmul', a, b)), 'options->lower_fdot'),
200 (('fdot4', a, b), ('fsum4', ('fmul', a, b)), 'options->lower_fdot'),
201 (('fsum2', a), ('fadd', 'a.x', 'a.y'), 'options->lower_fdot'),
202
203 # If x >= 0 and x <= 1: fsat(1 - x) == 1 - fsat(x) trivially
204 # If x < 0: 1 - fsat(x) => 1 - 0 => 1 and fsat(1 - x) => fsat(> 1) => 1
205 # If x > 1: 1 - fsat(x) => 1 - 1 => 0 and fsat(1 - x) => fsat(< 0) => 0
206 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
207
208 # 1 - ((1 - a) * (1 - b))
209 # 1 - (1 - a - b + a*b)
210 # 1 - 1 + a + b - a*b
211 # a + b - a*b
212 # a + b*(1 - a)
213 # b*(1 - a) + 1*a
214 # flrp(b, 1, a)
215 (('~fadd@32', 1.0, ('fneg', ('fmul', ('fadd', 1.0, ('fneg', a)), ('fadd', 1.0, ('fneg', b))))),
216 ('flrp', b, 1.0, a), '!options->lower_flrp32'),
217
218 # (a * #b + #c) << #d
219 # ((a * #b) << #d) + (#c << #d)
220 # (a * (#b << #d)) + (#c << #d)
221 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
222 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
223
224 # (a * #b) << #c
225 # a * (#b << #c)
226 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
227
228 # Comparison simplifications
229 (('~inot', ('flt', a, b)), ('fge', a, b)),
230 (('~inot', ('fge', a, b)), ('flt', a, b)),
231 (('inot', ('feq', a, b)), ('fne', a, b)),
232 (('inot', ('fne', a, b)), ('feq', a, b)),
233 (('inot', ('ilt', a, b)), ('ige', a, b)),
234 (('inot', ('ult', a, b)), ('uge', a, b)),
235 (('inot', ('ige', a, b)), ('ilt', a, b)),
236 (('inot', ('uge', a, b)), ('ult', a, b)),
237 (('inot', ('ieq', a, b)), ('ine', a, b)),
238 (('inot', ('ine', a, b)), ('ieq', a, b)),
239
240 (('iand', ('feq', a, b), ('fne', a, b)), False),
241 (('iand', ('flt', a, b), ('flt', b, a)), False),
242 (('iand', ('ieq', a, b), ('ine', a, b)), False),
243 (('iand', ('ilt', a, b), ('ilt', b, a)), False),
244 (('iand', ('ult', a, b), ('ult', b, a)), False),
245
246 # This helps some shaders because, after some optimizations, they end up
247 # with patterns like (-a < -b) || (b < a). In an ideal world, this sort of
248 # matching would be handled by CSE.
249 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
250 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
251 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
252 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
253 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
254 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
255 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
256 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
257 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
258 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
259
260 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
261 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
262 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
263 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
264 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
265 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
266
267 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
268 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
269 (('fge', 0.0, ('fsat(is_used_once)', a)), ('fge', 0.0, a)),
270 (('flt', 0.0, ('fsat(is_used_once)', a)), ('flt', 0.0, a)),
271
272 # 0.0 >= b2f(a)
273 # b2f(a) <= 0.0
274 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
275 # inot(a)
276 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
277
278 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
279
280 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
281 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
282 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
283 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
284 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
285 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
286 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
287 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
288 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
289 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
290 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
291 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
292 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
293 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
294 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
295 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
296 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
297 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
298 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
299 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
300
301 # -(b2f(a) + b2f(b)) < 0
302 # 0 < b2f(a) + b2f(b)
303 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
304 # a || b
305 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
306 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
307
308 # -(b2f(a) + b2f(b)) >= 0
309 # 0 >= b2f(a) + b2f(b)
310 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
311 # !(a || b)
312 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
313 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
314
315 (('flt', a, ('fneg', a)), ('flt', a, 0.0)),
316 (('fge', a, ('fneg', a)), ('fge', a, 0.0)),
317
318 # Some optimizations (below) convert things like (a < b || c < b) into
319 # (min(a, c) < b). However, this interfers with the previous optimizations
320 # that try to remove comparisons with negated sums of b2f. This just
321 # breaks that apart.
322 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
323 ('ior', ('flt', c, 0.0), ('ior', a, b))),
324
325 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
326 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
327 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
328 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
329
330 # Cannot remove the addition from ilt or ige due to overflow.
331 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
332 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
333
334 # fmin(-b2f(a), b) >= 0.0
335 # -b2f(a) >= 0.0 && b >= 0.0
336 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
337 # b2f(a) == 0.0 && b >= 0.0
338 # a == False && b >= 0.0
339 # !a && b >= 0.0
340 #
341 # The fge in the second replacement is not a typo. I leave the proof that
342 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
343 # reader.
344 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
345 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
346
347 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
348 (('fne', ('b2f', 'a@1'), 0.0), a),
349 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
350 (('ine', ('b2i', 'a@1'), 0), a),
351
352 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
353 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
354 (('fge', ('u2f', a), 0.0), True),
355 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
356 (('flt', ('u2f', a), 0.0), False),
357 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
358 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
359 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
360 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
361 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
362 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
363 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
364
365 # 0.0 < fabs(a)
366 # fabs(a) > 0.0
367 # fabs(a) != 0.0 because fabs(a) must be >= 0
368 # a != 0.0
369 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
370
371 # -fabs(a) < 0.0
372 # fabs(a) > 0.0
373 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
374
375 # 0.0 >= fabs(a)
376 # 0.0 == fabs(a) because fabs(a) must be >= 0
377 # 0.0 == a
378 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
379
380 # -fabs(a) >= 0.0
381 # 0.0 >= fabs(a)
382 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
383
384 # (a >= 0.0) && (a <= 1.0) -> fsat(a) == a
385 (('iand', ('fge', a, 0.0), ('fge', 1.0, a)), ('feq', a, ('fsat', a)), '!options->lower_fsat'),
386
387 # (a < 0.0) || (a > 1.0)
388 # !(!(a < 0.0) && !(a > 1.0))
389 # !((a >= 0.0) && (a <= 1.0))
390 # !(a == fsat(a))
391 # a != fsat(a)
392 (('ior', ('flt', a, 0.0), ('flt', 1.0, a)), ('fne', a, ('fsat', a)), '!options->lower_fsat'),
393
394 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
395 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
396 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
397 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
398
399 # fmin(b2f(a), b)
400 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
401 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
402 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
403 #
404 # Since b is a constant, constant folding will eliminate the fmin and the
405 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
406 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
407
408 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
409
410 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
411 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
412 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
413 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
414 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
415 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
416 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
417 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
418 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
419 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
420 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
421 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
422 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
423 (('bcsel', a, True, b), ('ior', a, b)),
424 (('bcsel', a, a, b), ('ior', a, b)),
425 (('bcsel', a, b, False), ('iand', a, b)),
426 (('bcsel', a, b, a), ('iand', a, b)),
427 (('fmin', a, a), a),
428 (('fmax', a, a), a),
429 (('imin', a, a), a),
430 (('imax', a, a), a),
431 (('umin', a, a), a),
432 (('umax', a, a), a),
433 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
434 (('umax', ('umax', a, b), b), ('umax', a, b)),
435 (('imax', ('imax', a, b), b), ('imax', a, b)),
436 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
437 (('umin', ('umin', a, b), b), ('umin', a, b)),
438 (('imin', ('imin', a, b), b), ('imin', a, b)),
439 (('fmax', a, ('fneg', a)), ('fabs', a)),
440 (('imax', a, ('ineg', a)), ('iabs', a)),
441 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
442 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
443 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
444 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
445 (('fmin', a, ('fabs', a)), a),
446 (('imin', a, ('iabs', a)), a),
447 (('fmax', a, ('fneg', ('fabs', a))), a),
448 (('imax', a, ('ineg', ('iabs', a))), a),
449 (('fmax', a, ('fabs', a)), ('fabs', a)),
450 (('imax', a, ('iabs', a)), ('iabs', a)),
451 (('fmax', a, ('fneg', a)), ('fabs', a)),
452 (('imax', a, ('ineg', a)), ('iabs', a)),
453 (('~fmax', ('fabs', a), 0.0), ('fabs', a)),
454 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
455 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
456 (('~fmin', ('fmax', a, -1.0), 0.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
457 (('~fmax', ('fmin', a, 0.0), -1.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
458 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
459 (('fsat', ('b2f', a)), ('b2f', a)),
460 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
461 (('fsat', ('fsat', a)), ('fsat', a)),
462 (('fsat', ('fneg(is_used_once)', ('fadd(is_used_once)', a, b))), ('fsat', ('fadd', ('fneg', a), ('fneg', b))), '!options->lower_negate && !options->lower_fsat'),
463 (('fsat', ('fneg(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fneg', a), b)), '!options->lower_negate && !options->lower_fsat'),
464 (('fsat', ('fabs(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fabs', a), ('fabs', b))), '!options->lower_fsat'),
465 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
466 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
467 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
468 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
469 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
470 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
471 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
472 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
473 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
474 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
475 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
476 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
477 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
478 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
479 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
480 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
481 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
482 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
483 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
484 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
485 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
486 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
487
488 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
489 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
490 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
491 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
492 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
493 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
494 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
495 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
496 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
497 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
498 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
499 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
500 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
501 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
502 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
503 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
504
505 # Common pattern like 'if (i == 0 || i == 1 || ...)'
506 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
507 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
508 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
509
510 # The (i2f32, ...) part is an open-coded fsign. When that is combined with
511 # the bcsel, it's basically copysign(1.0, a). There is no copysign in NIR,
512 # so emit an open-coded version of that.
513 (('bcsel@32', ('feq', a, 0.0), 1.0, ('i2f32', ('iadd', ('b2i32', ('flt', 0.0, 'a@32')), ('ineg', ('b2i32', ('flt', 'a@32', 0.0)))))),
514 ('ior', 0x3f800000, ('iand', a, 0x80000000))),
515
516 (('ior', a, ('ieq', a, False)), True),
517 (('ior', a, ('inot', a)), -1),
518
519 (('ine', ('ineg', ('b2i32', 'a@1')), ('ineg', ('b2i32', 'b@1'))), ('ine', a, b)),
520 (('b2i32', ('ine', 'a@1', 'b@1')), ('b2i32', ('ixor', a, b))),
521
522 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0), '!options->lower_bitops'),
523
524 # These patterns can result when (a < b || a < c) => (a < min(b, c))
525 # transformations occur before constant propagation and loop-unrolling.
526 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
527 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
528 (('~fge', a, ('fmin', b, a)), True),
529 (('~fge', ('fmax', a, b), a), True),
530 (('~flt', a, ('fmin', b, a)), False),
531 (('~flt', ('fmax', a, b), a), False),
532 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
533 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
534
535 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
536 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
537 (('ige', a, ('imin', b, a)), True),
538 (('ige', ('imax', a, b), a), True),
539 (('ult', a, ('umax', b, a)), ('ult', a, b)),
540 (('ult', ('umin', a, b), a), ('ult', b, a)),
541 (('uge', a, ('umin', b, a)), True),
542 (('uge', ('umax', a, b), a), True),
543 (('ilt', a, ('imin', b, a)), False),
544 (('ilt', ('imax', a, b), a), False),
545 (('ige', a, ('imax', b, a)), ('ige', a, b)),
546 (('ige', ('imin', a, b), a), ('ige', b, a)),
547 (('ult', a, ('umin', b, a)), False),
548 (('ult', ('umax', a, b), a), False),
549 (('uge', a, ('umax', b, a)), ('uge', a, b)),
550 (('uge', ('umin', a, b), a), ('uge', b, a)),
551 (('ult', a, ('iand', b, a)), False),
552 (('ult', ('ior', a, b), a), False),
553 (('uge', a, ('iand', b, a)), True),
554 (('uge', ('ior', a, b), a), True),
555
556 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
557 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
558 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
559 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
560 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
561 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
562 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
563 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
564 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
565 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
566 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
567 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
568 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
569 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
570 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
571 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
572
573 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
574 # negative.
575 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
576 ('iabs', ('ishr', a, b))),
577 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
578
579 (('fabs', ('slt', a, b)), ('slt', a, b)),
580 (('fabs', ('sge', a, b)), ('sge', a, b)),
581 (('fabs', ('seq', a, b)), ('seq', a, b)),
582 (('fabs', ('sne', a, b)), ('sne', a, b)),
583 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
584 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
585 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
586 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
587 (('seq', ('seq', a, b), 1.0), ('seq', a, b)),
588 (('seq', ('sne', a, b), 1.0), ('sne', a, b)),
589 (('seq', ('slt', a, b), 1.0), ('slt', a, b)),
590 (('seq', ('sge', a, b), 1.0), ('sge', a, b)),
591 (('sne', ('seq', a, b), 0.0), ('seq', a, b)),
592 (('sne', ('sne', a, b), 0.0), ('sne', a, b)),
593 (('sne', ('slt', a, b), 0.0), ('slt', a, b)),
594 (('sne', ('sge', a, b), 0.0), ('sge', a, b)),
595 (('seq', ('seq', a, b), 0.0), ('sne', a, b)),
596 (('seq', ('sne', a, b), 0.0), ('seq', a, b)),
597 (('seq', ('slt', a, b), 0.0), ('sge', a, b)),
598 (('seq', ('sge', a, b), 0.0), ('slt', a, b)),
599 (('sne', ('seq', a, b), 1.0), ('sne', a, b)),
600 (('sne', ('sne', a, b), 1.0), ('seq', a, b)),
601 (('sne', ('slt', a, b), 1.0), ('sge', a, b)),
602 (('sne', ('sge', a, b), 1.0), ('slt', a, b)),
603 (('fall_equal2', a, b), ('fmin', ('seq', 'a.x', 'b.x'), ('seq', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
604 (('fall_equal3', a, b), ('seq', ('fany_nequal3', a, b), 0.0), 'options->lower_vector_cmp'),
605 (('fall_equal4', a, b), ('seq', ('fany_nequal4', a, b), 0.0), 'options->lower_vector_cmp'),
606 (('fany_nequal2', a, b), ('fmax', ('sne', 'a.x', 'b.x'), ('sne', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
607 (('fany_nequal3', a, b), ('fsat', ('fdot3', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
608 (('fany_nequal4', a, b), ('fsat', ('fdot4', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
609 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
610 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
611 # Emulating booleans
612 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
613 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
614 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
615 (('iand', 'a@bool32', 1.0), ('b2f', a)),
616 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
617 (('ineg', ('b2i32', 'a@32')), a),
618 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
619 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
620 # Comparison with the same args. Note that these are not done for
621 # the float versions because NaN always returns false on float
622 # inequalities.
623 (('ilt', a, a), False),
624 (('ige', a, a), True),
625 (('ieq', a, a), True),
626 (('ine', a, a), False),
627 (('ult', a, a), False),
628 (('uge', a, a), True),
629 # Logical and bit operations
630 (('iand', a, a), a),
631 (('iand', a, ~0), a),
632 (('iand', a, 0), 0),
633 (('ior', a, a), a),
634 (('ior', a, 0), a),
635 (('ior', a, True), True),
636 (('ixor', a, a), 0),
637 (('ixor', a, 0), a),
638 (('inot', ('inot', a)), a),
639 (('ior', ('iand', a, b), b), b),
640 (('ior', ('ior', a, b), b), ('ior', a, b)),
641 (('iand', ('ior', a, b), b), b),
642 (('iand', ('iand', a, b), b), ('iand', a, b)),
643 # DeMorgan's Laws
644 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
645 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
646 # Shift optimizations
647 (('ishl', 0, a), 0),
648 (('ishl', a, 0), a),
649 (('ishr', 0, a), 0),
650 (('ishr', a, 0), a),
651 (('ushr', 0, a), 0),
652 (('ushr', a, 0), a),
653 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
654 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
655 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('iadd', 16, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
656 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('isub', 16, b))), ('urol', a, b), '!options->lower_rotate'),
657 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('iadd', 32, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
658 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('isub', 32, b))), ('urol', a, b), '!options->lower_rotate'),
659 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('iadd', 16, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
660 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('isub', 16, b))), ('uror', a, b), '!options->lower_rotate'),
661 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('iadd', 32, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
662 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('isub', 32, b))), ('uror', a, b), '!options->lower_rotate'),
663 (('urol@16', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 16, b))), 'options->lower_rotate'),
664 (('urol@32', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 32, b))), 'options->lower_rotate'),
665 (('uror@16', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 16, b))), 'options->lower_rotate'),
666 (('uror@32', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 32, b))), 'options->lower_rotate'),
667 # Exponential/logarithmic identities
668 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
669 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
670 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
671 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
672 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
673 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
674 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
675 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
676 (('~fpow', a, 1.0), a),
677 (('~fpow', a, 2.0), ('fmul', a, a)),
678 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
679 (('~fpow', 2.0, a), ('fexp2', a)),
680 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
681 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
682 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
683 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
684 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
685 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
686 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
687 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
688 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
689 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
690 (('bcsel', ('flt', a, 0.0), 0.0, ('fsqrt', a)), ('fsqrt', ('fmax', a, 0.0))),
691 # Division and reciprocal
692 (('~fdiv', 1.0, a), ('frcp', a)),
693 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
694 (('~frcp', ('frcp', a)), a),
695 (('~frcp', ('fsqrt', a)), ('frsq', a)),
696 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
697 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
698 # Trig
699 (('fsin', a), lowered_sincos(0.5), 'options->lower_sincos'),
700 (('fcos', a), lowered_sincos(0.75), 'options->lower_sincos'),
701 # Boolean simplifications
702 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
703 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
704 (('ieq', a, True), a),
705 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
706 (('ine', a, False), a),
707 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
708 (('bcsel', a, True, False), a),
709 (('bcsel', a, False, True), ('inot', a)),
710 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
711 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
712 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
713 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
714 (('bcsel', True, b, c), b),
715 (('bcsel', False, b, c), c),
716 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
717
718 (('bcsel', a, b, b), b),
719 (('fcsel', a, b, b), b),
720
721 # D3D Boolean emulation
722 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
723 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
724 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
725 ('ineg', ('b2i', ('iand', a, b)))),
726 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
727 ('ineg', ('b2i', ('ior', a, b)))),
728 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
729 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
730 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
731 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
732 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
733
734 # SM5 32-bit shifts are defined to use the 5 least significant bits
735 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
736 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
737 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
738
739 # Conversions
740 (('i2b32', ('b2i', 'a@32')), a),
741 (('f2i', ('ftrunc', a)), ('f2i', a)),
742 (('f2u', ('ftrunc', a)), ('f2u', a)),
743 (('i2b', ('ineg', a)), ('i2b', a)),
744 (('i2b', ('iabs', a)), ('i2b', a)),
745 (('fabs', ('b2f', a)), ('b2f', a)),
746 (('iabs', ('b2i', a)), ('b2i', a)),
747 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
748
749 # Ironically, mark these as imprecise because removing the conversions may
750 # preserve more precision than doing the conversions (e.g.,
751 # uint(float(0x81818181u)) == 0x81818200).
752 (('~f2i32', ('i2f', 'a@32')), a),
753 (('~f2i32', ('u2f', 'a@32')), a),
754 (('~f2u32', ('i2f', 'a@32')), a),
755 (('~f2u32', ('u2f', 'a@32')), a),
756
757 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
758 # says:
759 #
760 # It is undefined to convert a negative floating-point value to an
761 # uint.
762 #
763 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
764 # some optimizations in the i965 backend to proceed.
765 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
766 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
767 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
768 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
769
770 (('~fmin', ('fabs', a), 1.0), ('fsat', ('fabs', a)), '!options->lower_fsat'),
771
772 # The result of the multiply must be in [-1, 0], so the result of the ffma
773 # must be in [0, 1].
774 (('flt', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), False),
775 (('flt', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), False),
776 (('fmax', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0)),
777 (('fmax', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0)),
778
779 # Packing and then unpacking does nothing
780 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
781 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
782 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
783 ('unpack_64_2x32_split_y', a)), a),
784
785 # Comparing two halves of an unpack separately. While this optimization
786 # should be correct for non-constant values, it's less obvious that it's
787 # useful in that case. For constant values, the pack will fold and we're
788 # guaranteed to reduce the whole tree to one instruction.
789 (('iand', ('ieq', ('unpack_32_2x16_split_x', a), '#b'),
790 ('ieq', ('unpack_32_2x16_split_y', a), '#c')),
791 ('ieq', a, ('pack_32_2x16_split', b, c))),
792
793 # Byte extraction
794 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
795 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
796 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
797 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
798 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
799 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
800 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
801 ]
802
803 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
804 # patterns like those below.
805 for op in ('ushr', 'ishr'):
806 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
807 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
808 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
809
810 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
811
812 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
813 # patterns like those below.
814 for op in ('extract_u8', 'extract_i8'):
815 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
816 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
817 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
818
819 optimizations.extend([
820 # Word extraction
821 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
822 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
823 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
824 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
825 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
826
827 # Subtracts
828 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
829 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
830 (('ussub_4x8', a, 0), a),
831 (('ussub_4x8', a, ~0), 0),
832 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
833 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
834 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
835 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
836 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
837 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
838 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
839 (('iabs', ('isub', 0, a)), ('iabs', a)),
840
841 # Propagate negation up multiplication chains
842 (('fmul(is_used_by_non_fsat)', ('fneg', a), b), ('fneg', ('fmul', a, b))),
843 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
844
845 # Propagate constants up multiplication chains
846 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
847 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
848 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
849 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
850
851 # Reassociate constants in add/mul chains so they can be folded together.
852 # For now, we mostly only handle cases where the constants are separated by
853 # a single non-constant. We could do better eventually.
854 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
855 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
856 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
857 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
858 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
859
860 # Drop mul-div by the same value when there's no wrapping.
861 (('idiv', ('imul(no_signed_wrap)', a, b), b), a),
862
863 # By definition...
864 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
865 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
866 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
867
868 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
869 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
870 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
871
872 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
873
874 # Misc. lowering
875 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
876 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
877 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
878 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
879 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
880
881 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
882 ('bcsel', ('ult', 31, 'bits'), 'insert',
883 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
884 'options->lower_bitfield_insert'),
885 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
886 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
887 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
888 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
889 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
890 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
891
892 # Alternative lowering that doesn't rely on bfi.
893 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
894 ('bcsel', ('ult', 31, 'bits'),
895 'insert',
896 (('ior',
897 ('iand', 'base', ('inot', ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))),
898 ('iand', ('ishl', 'insert', 'offset'), ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))))),
899 'options->lower_bitfield_insert_to_shifts'),
900
901 # Alternative lowering that uses bitfield_select.
902 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
903 ('bcsel', ('ult', 31, 'bits'), 'insert',
904 ('bitfield_select', ('bfm', 'bits', 'offset'), ('ishl', 'insert', 'offset'), 'base')),
905 'options->lower_bitfield_insert_to_bitfield_select'),
906
907 (('ibitfield_extract', 'value', 'offset', 'bits'),
908 ('bcsel', ('ult', 31, 'bits'), 'value',
909 ('ibfe', 'value', 'offset', 'bits')),
910 'options->lower_bitfield_extract'),
911
912 (('ubitfield_extract', 'value', 'offset', 'bits'),
913 ('bcsel', ('ult', 31, 'bits'), 'value',
914 ('ubfe', 'value', 'offset', 'bits')),
915 'options->lower_bitfield_extract'),
916
917 # Note that these opcodes are defined to only use the five least significant bits of 'offset' and 'bits'
918 (('ubfe', 'value', 'offset', ('iand', 31, 'bits')), ('ubfe', 'value', 'offset', 'bits')),
919 (('ubfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ubfe', 'value', 'offset', 'bits')),
920 (('ibfe', 'value', 'offset', ('iand', 31, 'bits')), ('ibfe', 'value', 'offset', 'bits')),
921 (('ibfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ibfe', 'value', 'offset', 'bits')),
922 (('bfm', 'bits', ('iand', 31, 'offset')), ('bfm', 'bits', 'offset')),
923 (('bfm', ('iand', 31, 'bits'), 'offset'), ('bfm', 'bits', 'offset')),
924
925 (('ibitfield_extract', 'value', 'offset', 'bits'),
926 ('bcsel', ('ieq', 0, 'bits'),
927 0,
928 ('ishr',
929 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
930 ('isub', 32, 'bits'))),
931 'options->lower_bitfield_extract_to_shifts'),
932
933 (('ubitfield_extract', 'value', 'offset', 'bits'),
934 ('iand',
935 ('ushr', 'value', 'offset'),
936 ('bcsel', ('ieq', 'bits', 32),
937 0xffffffff,
938 ('isub', ('ishl', 1, 'bits'), 1))),
939 'options->lower_bitfield_extract_to_shifts'),
940
941 (('ifind_msb', 'value'),
942 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
943 'options->lower_ifind_msb'),
944
945 (('find_lsb', 'value'),
946 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
947 'options->lower_find_lsb'),
948
949 (('extract_i8', a, 'b@32'),
950 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
951 'options->lower_extract_byte'),
952
953 (('extract_u8', a, 'b@32'),
954 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
955 'options->lower_extract_byte'),
956
957 (('extract_i16', a, 'b@32'),
958 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
959 'options->lower_extract_word'),
960
961 (('extract_u16', a, 'b@32'),
962 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
963 'options->lower_extract_word'),
964
965 (('pack_unorm_2x16', 'v'),
966 ('pack_uvec2_to_uint',
967 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
968 'options->lower_pack_unorm_2x16'),
969
970 (('pack_unorm_4x8', 'v'),
971 ('pack_uvec4_to_uint',
972 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
973 'options->lower_pack_unorm_4x8'),
974
975 (('pack_snorm_2x16', 'v'),
976 ('pack_uvec2_to_uint',
977 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
978 'options->lower_pack_snorm_2x16'),
979
980 (('pack_snorm_4x8', 'v'),
981 ('pack_uvec4_to_uint',
982 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
983 'options->lower_pack_snorm_4x8'),
984
985 (('unpack_unorm_2x16', 'v'),
986 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
987 ('extract_u16', 'v', 1))),
988 65535.0),
989 'options->lower_unpack_unorm_2x16'),
990
991 (('unpack_unorm_4x8', 'v'),
992 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
993 ('extract_u8', 'v', 1),
994 ('extract_u8', 'v', 2),
995 ('extract_u8', 'v', 3))),
996 255.0),
997 'options->lower_unpack_unorm_4x8'),
998
999 (('unpack_snorm_2x16', 'v'),
1000 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
1001 ('extract_i16', 'v', 1))),
1002 32767.0))),
1003 'options->lower_unpack_snorm_2x16'),
1004
1005 (('unpack_snorm_4x8', 'v'),
1006 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
1007 ('extract_i8', 'v', 1),
1008 ('extract_i8', 'v', 2),
1009 ('extract_i8', 'v', 3))),
1010 127.0))),
1011 'options->lower_unpack_snorm_4x8'),
1012
1013 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
1014 (('fsign', a), ('fsub', ('b2f', ('flt', 0.0, a)), ('b2f', ('flt', a, 0.0))), 'options->lower_fsign'),
1015 ])
1016
1017 # bit_size dependent lowerings
1018 for bit_size in [8, 16, 32, 64]:
1019 # convenience constants
1020 intmax = (1 << (bit_size - 1)) - 1
1021 intmin = 1 << (bit_size - 1)
1022
1023 optimizations += [
1024 (('iadd_sat@' + str(bit_size), a, b),
1025 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
1026 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
1027 (('isub_sat@' + str(bit_size), a, b),
1028 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
1029 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
1030 ]
1031
1032 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
1033
1034 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
1035 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
1036 ('iand', (invert[left], a, b), (invert[right], c, d))))
1037 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
1038 ('ior', (invert[left], a, b), (invert[right], c, d))))
1039
1040 # Optimize x2bN(b2x(x)) -> x
1041 for size in type_sizes('bool'):
1042 aN = 'a@' + str(size)
1043 f2bN = 'f2b' + str(size)
1044 i2bN = 'i2b' + str(size)
1045 optimizations.append(((f2bN, ('b2f', aN)), a))
1046 optimizations.append(((i2bN, ('b2i', aN)), a))
1047
1048 # Optimize x2yN(b2x(x)) -> b2y
1049 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
1050 if x != 'f' and y != 'f' and x != y:
1051 continue
1052
1053 b2x = 'b2f' if x == 'f' else 'b2i'
1054 b2y = 'b2f' if y == 'f' else 'b2i'
1055 x2yN = '{}2{}'.format(x, y)
1056 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
1057
1058 # Optimize away x2xN(a@N)
1059 for t in ['int', 'uint', 'float']:
1060 for N in type_sizes(t):
1061 x2xN = '{0}2{0}{1}'.format(t[0], N)
1062 aN = 'a@{0}'.format(N)
1063 optimizations.append(((x2xN, aN), a))
1064
1065 # Optimize x2xN(y2yM(a@P)) -> y2yN(a) for integers
1066 # In particular, we can optimize away everything except upcast of downcast and
1067 # upcasts where the type differs from the other cast
1068 for N, M in itertools.product(type_sizes('uint'), type_sizes('uint')):
1069 if N < M:
1070 # The outer cast is a down-cast. It doesn't matter what the size of the
1071 # argument of the inner cast is because we'll never been in the upcast
1072 # of downcast case. Regardless of types, we'll always end up with y2yN
1073 # in the end.
1074 for x, y in itertools.product(['i', 'u'], ['i', 'u']):
1075 x2xN = '{0}2{0}{1}'.format(x, N)
1076 y2yM = '{0}2{0}{1}'.format(y, M)
1077 y2yN = '{0}2{0}{1}'.format(y, N)
1078 optimizations.append(((x2xN, (y2yM, a)), (y2yN, a)))
1079 elif N > M:
1080 # If the outer cast is an up-cast, we have to be more careful about the
1081 # size of the argument of the inner cast and with types. In this case,
1082 # the type is always the type of type up-cast which is given by the
1083 # outer cast.
1084 for P in type_sizes('uint'):
1085 # We can't optimize away up-cast of down-cast.
1086 if M < P:
1087 continue
1088
1089 # Because we're doing down-cast of down-cast, the types always have
1090 # to match between the two casts
1091 for x in ['i', 'u']:
1092 x2xN = '{0}2{0}{1}'.format(x, N)
1093 x2xM = '{0}2{0}{1}'.format(x, M)
1094 aP = 'a@{0}'.format(P)
1095 optimizations.append(((x2xN, (x2xM, aP)), (x2xN, a)))
1096 else:
1097 # The N == M case is handled by other optimizations
1098 pass
1099
1100 # Optimize comparisons with up-casts
1101 for t in ['int', 'uint', 'float']:
1102 for N, M in itertools.product(type_sizes(t), repeat=2):
1103 if N == 1 or N >= M:
1104 continue
1105
1106 x2xM = '{0}2{0}{1}'.format(t[0], M)
1107 x2xN = '{0}2{0}{1}'.format(t[0], N)
1108 aN = 'a@' + str(N)
1109 bN = 'b@' + str(N)
1110 xeq = 'feq' if t == 'float' else 'ieq'
1111 xne = 'fne' if t == 'float' else 'ine'
1112 xge = '{0}ge'.format(t[0])
1113 xlt = '{0}lt'.format(t[0])
1114
1115 # Up-casts are lossless so for correctly signed comparisons of
1116 # up-casted values we can do the comparison at the largest of the two
1117 # original sizes and drop one or both of the casts. (We have
1118 # optimizations to drop the no-op casts which this may generate.)
1119 for P in type_sizes(t):
1120 if P == 1 or P > N:
1121 continue
1122
1123 bP = 'b@' + str(P)
1124 optimizations += [
1125 ((xeq, (x2xM, aN), (x2xM, bP)), (xeq, a, (x2xN, b))),
1126 ((xne, (x2xM, aN), (x2xM, bP)), (xne, a, (x2xN, b))),
1127 ((xge, (x2xM, aN), (x2xM, bP)), (xge, a, (x2xN, b))),
1128 ((xlt, (x2xM, aN), (x2xM, bP)), (xlt, a, (x2xN, b))),
1129 ((xge, (x2xM, bP), (x2xM, aN)), (xge, (x2xN, b), a)),
1130 ((xlt, (x2xM, bP), (x2xM, aN)), (xlt, (x2xN, b), a)),
1131 ]
1132
1133 # The next bit doesn't work on floats because the range checks would
1134 # get way too complicated.
1135 if t in ['int', 'uint']:
1136 if t == 'int':
1137 xN_min = -(1 << (N - 1))
1138 xN_max = (1 << (N - 1)) - 1
1139 elif t == 'uint':
1140 xN_min = 0
1141 xN_max = (1 << N) - 1
1142 else:
1143 assert False
1144
1145 # If we're up-casting and comparing to a constant, we can unfold
1146 # the comparison into a comparison with the shrunk down constant
1147 # and a check that the constant fits in the smaller bit size.
1148 optimizations += [
1149 ((xeq, (x2xM, aN), '#b'),
1150 ('iand', (xeq, a, (x2xN, b)), (xeq, (x2xM, (x2xN, b)), b))),
1151 ((xne, (x2xM, aN), '#b'),
1152 ('ior', (xne, a, (x2xN, b)), (xne, (x2xM, (x2xN, b)), b))),
1153 ((xlt, (x2xM, aN), '#b'),
1154 ('iand', (xlt, xN_min, b),
1155 ('ior', (xlt, xN_max, b), (xlt, a, (x2xN, b))))),
1156 ((xlt, '#a', (x2xM, bN)),
1157 ('iand', (xlt, a, xN_max),
1158 ('ior', (xlt, a, xN_min), (xlt, (x2xN, a), b)))),
1159 ((xge, (x2xM, aN), '#b'),
1160 ('iand', (xge, xN_max, b),
1161 ('ior', (xge, xN_min, b), (xge, a, (x2xN, b))))),
1162 ((xge, '#a', (x2xM, bN)),
1163 ('iand', (xge, a, xN_min),
1164 ('ior', (xge, a, xN_max), (xge, (x2xN, a), b)))),
1165 ]
1166
1167 def fexp2i(exp, bits):
1168 # We assume that exp is already in the right range.
1169 if bits == 16:
1170 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
1171 elif bits == 32:
1172 return ('ishl', ('iadd', exp, 127), 23)
1173 elif bits == 64:
1174 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
1175 else:
1176 assert False
1177
1178 def ldexp(f, exp, bits):
1179 # First, we clamp exp to a reasonable range. The maximum possible range
1180 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
1181 # a maximum range of [-149, 127]. This means that we can potentially have
1182 # a swing of +-276. If you start with FLT_MAX, you actually have to do
1183 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
1184 # spec, on the other hand, only requires that we handle an exponent value
1185 # in the range [-126, 128]. This implementation is *mostly* correct; it
1186 # handles a range on exp of [-252, 254] which allows you to create any
1187 # value (including denorms if the hardware supports it) and to adjust the
1188 # exponent of any normal value to anything you want.
1189 if bits == 16:
1190 exp = ('imin', ('imax', exp, -28), 30)
1191 elif bits == 32:
1192 exp = ('imin', ('imax', exp, -252), 254)
1193 elif bits == 64:
1194 exp = ('imin', ('imax', exp, -2044), 2046)
1195 else:
1196 assert False
1197
1198 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
1199 # (We use ishr which isn't the same for -1, but the -1 case still works
1200 # since we use exp-exp/2 as the second exponent.) While the spec
1201 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
1202 # work with denormals and doesn't allow for the full swing in exponents
1203 # that you can get with normalized values. Instead, we create two powers
1204 # of two and multiply by them each in turn. That way the effective range
1205 # of our exponent is doubled.
1206 pow2_1 = fexp2i(('ishr', exp, 1), bits)
1207 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
1208 return ('fmul', ('fmul', f, pow2_1), pow2_2)
1209
1210 optimizations += [
1211 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
1212 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
1213 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
1214 ]
1215
1216 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
1217 def bitfield_reverse(u):
1218 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
1219 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
1220 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
1221 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
1222 step5 = ('ior(many-comm-expr)', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
1223
1224 return step5
1225
1226 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
1227
1228 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
1229 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
1230 # and, if a is a NaN then the second comparison will fail anyway.
1231 for op in ['flt', 'fge', 'feq']:
1232 optimizations += [
1233 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
1234 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
1235 ]
1236
1237 # Add optimizations to handle the case where the result of a ternary is
1238 # compared to a constant. This way we can take things like
1239 #
1240 # (a ? 0 : 1) > 0
1241 #
1242 # and turn it into
1243 #
1244 # a ? (0 > 0) : (1 > 0)
1245 #
1246 # which constant folding will eat for lunch. The resulting ternary will
1247 # further get cleaned up by the boolean reductions above and we will be
1248 # left with just the original variable "a".
1249 for op in ['flt', 'fge', 'feq', 'fne',
1250 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
1251 optimizations += [
1252 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
1253 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
1254 ((op, '#d', ('bcsel', a, '#b', '#c')),
1255 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
1256 ]
1257
1258
1259 # For example, this converts things like
1260 #
1261 # 1 + mix(0, a - 1, condition)
1262 #
1263 # into
1264 #
1265 # mix(1, (a-1)+1, condition)
1266 #
1267 # Other optimizations will rearrange the constants.
1268 for op in ['fadd', 'fmul', 'iadd', 'imul']:
1269 optimizations += [
1270 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
1271 ]
1272
1273 # For derivatives in compute shaders, GLSL_NV_compute_shader_derivatives
1274 # states:
1275 #
1276 # If neither layout qualifier is specified, derivatives in compute shaders
1277 # return zero, which is consistent with the handling of built-in texture
1278 # functions like texture() in GLSL 4.50 compute shaders.
1279 for op in ['fddx', 'fddx_fine', 'fddx_coarse',
1280 'fddy', 'fddy_fine', 'fddy_coarse']:
1281 optimizations += [
1282 ((op, 'a'), 0.0, 'info->stage == MESA_SHADER_COMPUTE && info->cs.derivative_group == DERIVATIVE_GROUP_NONE')
1283 ]
1284
1285 # Some optimizations for ir3-specific instructions.
1286 optimizations += [
1287 # 'al * bl': If either 'al' or 'bl' is zero, return zero.
1288 (('umul_low', '#a(is_lower_half_zero)', 'b'), (0)),
1289 # '(ah * bl) << 16 + c': If either 'ah' or 'bl' is zero, return 'c'.
1290 (('imadsh_mix16', '#a@32(is_lower_half_zero)', 'b@32', 'c@32'), ('c')),
1291 (('imadsh_mix16', 'a@32', '#b@32(is_upper_half_zero)', 'c@32'), ('c')),
1292 ]
1293
1294 # This section contains "late" optimizations that should be run before
1295 # creating ffmas and calling regular optimizations for the final time.
1296 # Optimizations should go here if they help code generation and conflict
1297 # with the regular optimizations.
1298 before_ffma_optimizations = [
1299 # Propagate constants down multiplication chains
1300 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
1301 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
1302 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
1303 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
1304
1305 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
1306 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
1307 (('~fadd', ('fneg', a), a), 0.0),
1308 (('iadd', ('ineg', a), a), 0),
1309 (('iadd', ('ineg', a), ('iadd', a, b)), b),
1310 (('iadd', a, ('iadd', ('ineg', a), b)), b),
1311 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
1312 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
1313
1314 (('~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)),
1315 (('~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)),
1316 (('~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))),
1317 ]
1318
1319 # This section contains "late" optimizations that should be run after the
1320 # regular optimizations have finished. Optimizations should go here if
1321 # they help code generation but do not necessarily produce code that is
1322 # more easily optimizable.
1323 late_optimizations = [
1324 # Most of these optimizations aren't quite safe when you get infinity or
1325 # Nan involved but the first one should be fine.
1326 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1327 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1328 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1329 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1330 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1331 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1332
1333 # nir_lower_to_source_mods will collapse this, but its existence during the
1334 # optimization loop can prevent other optimizations.
1335 (('fneg', ('fneg', a)), a),
1336
1337 # These are duplicated from the main optimizations table. The late
1338 # patterns that rearrange expressions like x - .5 < 0 to x < .5 can create
1339 # new patterns like these. The patterns that compare with zero are removed
1340 # because they are unlikely to be created in by anything in
1341 # late_optimizations.
1342 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
1343 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
1344 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
1345 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
1346 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
1347 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
1348
1349 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
1350 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
1351
1352 (('~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)))),
1353
1354 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
1355 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
1356 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
1357 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
1358 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
1359 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
1360 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
1361 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
1362 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
1363 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
1364
1365 (('ior', a, a), a),
1366 (('iand', a, a), a),
1367
1368 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
1369
1370 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1371 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1372 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1373 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1374
1375 (('~flrp@32', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1376 (('~flrp@64', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1377
1378 (('~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'),
1379 (('~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'),
1380
1381 # A similar operation could apply to any ffma(#a, b, #(-a/2)), but this
1382 # particular operation is common for expanding values stored in a texture
1383 # from [0,1] to [-1,1].
1384 (('~ffma@32', a, 2.0, -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1385 (('~ffma@32', a, -2.0, -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1386 (('~ffma@32', a, -2.0, 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1387 (('~ffma@32', a, 2.0, 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1388 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1389 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1390 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1391 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1392
1393 # flrp(a, b, a)
1394 # a*(1-a) + b*a
1395 # a + -a*a + a*b (1)
1396 # a + a*(b - a)
1397 # Option 1: ffma(a, (b-a), a)
1398 #
1399 # Alternately, after (1):
1400 # a*(1+b) + -a*a
1401 # a*((1+b) + -a)
1402 #
1403 # Let b=1
1404 #
1405 # Option 2: ffma(a, 2, -(a*a))
1406 # Option 3: ffma(a, 2, (-a)*a)
1407 # Option 4: ffma(a, -a, (2*a)
1408 # Option 5: a * (2 - a)
1409 #
1410 # There are a lot of other possible combinations.
1411 (('~ffma@32', ('fadd', b, ('fneg', a)), a, a), ('flrp', a, b, a), '!options->lower_flrp32'),
1412 (('~ffma@32', a, 2.0, ('fneg', ('fmul', a, a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1413 (('~ffma@32', a, 2.0, ('fmul', ('fneg', a), a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1414 (('~ffma@32', a, ('fneg', a), ('fmul', 2.0, a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1415 (('~fmul@32', a, ('fadd', 2.0, ('fneg', a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1416
1417 # we do these late so that we don't get in the way of creating ffmas
1418 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1419 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1420
1421 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1422
1423 # Things that look like DPH in the source shader may get expanded to
1424 # something that looks like dot(v1.xyz, v2.xyz) + v1.w by the time it gets
1425 # to NIR. After FFMA is generated, this can look like:
1426 #
1427 # fadd(ffma(v1.z, v2.z, ffma(v1.y, v2.y, fmul(v1.x, v2.x))), v1.w)
1428 #
1429 # Reassociate the last addition into the first multiplication.
1430 (('~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)'),
1431 ('ffma', a, b, ('ffma', c, d, ('ffma', e, 'f', 'g'))), '!options->intel_vec4'),
1432 (('~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)'),
1433 ('ffma', a, b, ('ffma', e, 'f', 'g') ), '!options->intel_vec4'),
1434 ]
1435
1436 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1437 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1438 before_ffma_optimizations).render())
1439 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1440 late_optimizations).render())