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