nir: Move panfrost's isign lowering to nir_opt_algebraic.
[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
33 # Convenience variables
34 a = 'a'
35 b = 'b'
36 c = 'c'
37 d = 'd'
38
39 # Written in the form (<search>, <replace>) where <search> is an expression
40 # and <replace> is either an expression or a value. An expression is
41 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
42 # where each source is either an expression or a value. A value can be
43 # either a numeric constant or a string representing a variable name.
44 #
45 # If the opcode in a search expression is prefixed by a '~' character, this
46 # indicates that the operation is inexact. Such operations will only get
47 # applied to SSA values that do not have the exact bit set. This should be
48 # used by by any optimizations that are not bit-for-bit exact. It should not,
49 # however, be used for backend-requested lowering operations as those need to
50 # happen regardless of precision.
51 #
52 # Variable names are specified as "[#]name[@type][(cond)]" where "#" inicates
53 # that the given variable will only match constants and the type indicates that
54 # the given variable will only match values from ALU instructions with the
55 # given output type, and (cond) specifies an additional condition function
56 # (see nir_search_helpers.h).
57 #
58 # For constants, you have to be careful to make sure that it is the right
59 # type because python is unaware of the source and destination types of the
60 # opcodes.
61 #
62 # All expression types can have a bit-size specified. For opcodes, this
63 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
64 # type and size. In the search half of the expression this indicates that it
65 # should only match that particular bit-size. In the replace half of the
66 # expression this indicates that the constructed value should have that
67 # bit-size.
68
69 optimizations = [
70
71 (('imul', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b))),
72 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b))))),
73 (('udiv', a, 1), a),
74 (('idiv', a, 1), a),
75 (('umod', a, 1), 0),
76 (('imod', a, 1), 0),
77 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b))),
78 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
79 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
80 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
81
82 (('fneg', ('fneg', a)), a),
83 (('ineg', ('ineg', a)), a),
84 (('fabs', ('fabs', a)), ('fabs', a)),
85 (('fabs', ('fneg', a)), ('fabs', a)),
86 (('fabs', ('u2f', a)), ('u2f', a)),
87 (('iabs', ('iabs', a)), ('iabs', a)),
88 (('iabs', ('ineg', a)), ('iabs', a)),
89 (('f2b', ('fneg', a)), ('f2b', a)),
90 (('i2b', ('ineg', a)), ('i2b', a)),
91 (('~fadd', a, 0.0), a),
92 (('iadd', a, 0), a),
93 (('usadd_4x8', a, 0), a),
94 (('usadd_4x8', a, ~0), ~0),
95 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
96 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
97 (('~fadd', ('fneg', a), a), 0.0),
98 (('iadd', ('ineg', a), a), 0),
99 (('iadd', ('ineg', a), ('iadd', a, b)), b),
100 (('iadd', a, ('iadd', ('ineg', a), b)), b),
101 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
102 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
103 (('~fmul', a, 0.0), 0.0),
104 (('imul', a, 0), 0),
105 (('umul_unorm_4x8', a, 0), 0),
106 (('umul_unorm_4x8', a, ~0), a),
107 (('fmul', a, 1.0), a),
108 (('imul', a, 1), a),
109 (('fmul', a, -1.0), ('fneg', a)),
110 (('imul', a, -1), ('ineg', a)),
111 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
112 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
113 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
114 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
115 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
116 (('~ffma', 0.0, a, b), b),
117 (('~ffma', a, 0.0, b), b),
118 (('~ffma', a, b, 0.0), ('fmul', a, b)),
119 (('ffma', a, 1.0, b), ('fadd', a, b)),
120 (('ffma', 1.0, a, b), ('fadd', a, b)),
121 (('~flrp', a, b, 0.0), a),
122 (('~flrp', a, b, 1.0), b),
123 (('~flrp', a, a, b), a),
124 (('~flrp', 0.0, a, b), ('fmul', a, b)),
125 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
126 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
127 (('flrp@32', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp32'),
128 (('flrp@64', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp64'),
129 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
130 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
131 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
132 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
133 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ))), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
134 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ))), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
135 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
136 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
137 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
138 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
139 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
140
141 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d)),
142 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
143 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
144 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
145
146 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
147 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
148
149 # (a * #b + #c) << #d
150 # ((a * #b) << #d) + (#c << #d)
151 # (a * (#b << #d)) + (#c << #d)
152 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
153 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
154
155 # (a * #b) << #c
156 # a * (#b << #c)
157 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
158
159 # Comparison simplifications
160 (('~inot', ('flt', a, b)), ('fge', a, b)),
161 (('~inot', ('fge', a, b)), ('flt', a, b)),
162 (('~inot', ('feq', a, b)), ('fne', a, b)),
163 (('~inot', ('fne', a, b)), ('feq', a, b)),
164 (('inot', ('ilt', a, b)), ('ige', a, b)),
165 (('inot', ('ult', a, b)), ('uge', a, b)),
166 (('inot', ('ige', a, b)), ('ilt', a, b)),
167 (('inot', ('uge', a, b)), ('ult', a, b)),
168 (('inot', ('ieq', a, b)), ('ine', a, b)),
169 (('inot', ('ine', a, b)), ('ieq', a, b)),
170
171 # 0.0 >= b2f(a)
172 # b2f(a) <= 0.0
173 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
174 # inot(a)
175 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
176
177 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
178
179 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
180 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
181 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
182 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
183 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
184 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
185 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
186 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
187 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
188 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
189 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
190 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
191 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
192 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
193 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
194 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
195 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
196 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
197 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
198 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
199
200 # -(b2f(a) + b2f(b)) < 0
201 # 0 < b2f(a) + b2f(b)
202 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
203 # a || b
204 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
205 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
206
207 # -(b2f(a) + b2f(b)) >= 0
208 # 0 >= b2f(a) + b2f(b)
209 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
210 # !(a || b)
211 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
212 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
213
214 # Some optimizations (below) convert things like (a < b || c < b) into
215 # (min(a, c) < b). However, this interfers with the previous optimizations
216 # that try to remove comparisons with negated sums of b2f. This just
217 # breaks that apart.
218 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
219 ('ior', ('flt', c, 0.0), ('ior', a, b))),
220
221 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
222 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
223 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
224 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
225
226 # Cannot remove the addition from ilt or ige due to overflow.
227 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
228 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
229
230 # fmin(-b2f(a), b) >= 0.0
231 # -b2f(a) >= 0.0 && b >= 0.0
232 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
233 # b2f(a) == 0.0 && b >= 0.0
234 # a == False && b >= 0.0
235 # !a && b >= 0.0
236 #
237 # The fge in the second replacement is not a typo. I leave the proof that
238 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
239 # reader.
240 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
241 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
242
243 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
244 (('fne', ('b2f', 'a@1'), 0.0), a),
245 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
246 (('ine', ('b2i', 'a@1'), 0), a),
247
248 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
249 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
250 (('fge', ('u2f', a), 0.0), True),
251 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
252 (('flt', ('u2f', a), 0.0), False),
253 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
254 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
255 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
256 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
257 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
258 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
259 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
260
261 # 0.0 < fabs(a)
262 # fabs(a) > 0.0
263 # fabs(a) != 0.0 because fabs(a) must be >= 0
264 # a != 0.0
265 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
266
267 # -fabs(a) < 0.0
268 # fabs(a) > 0.0
269 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
270
271 # 0.0 >= fabs(a)
272 # 0.0 == fabs(a) because fabs(a) must be >= 0
273 # 0.0 == a
274 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
275
276 # -fabs(a) >= 0.0
277 # 0.0 >= fabs(a)
278 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
279
280 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
281 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
282 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
283 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
284
285 # fmin(b2f(a), b)
286 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
287 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
288 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
289 #
290 # Since b is a constant, constant folding will eliminate the fmin and the
291 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
292 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
293
294 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
295
296 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
297 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
298 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
299 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
300 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
301 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
302 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
303 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
304 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
305 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
306 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
307 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
308 (('bcsel', a, True, 'b@bool'), ('ior', a, b)),
309 (('fmin', a, a), a),
310 (('fmax', a, a), a),
311 (('imin', a, a), a),
312 (('imax', a, a), a),
313 (('umin', a, a), a),
314 (('umax', a, a), a),
315 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
316 (('umax', ('umax', a, b), b), ('umax', a, b)),
317 (('imax', ('imax', a, b), b), ('imax', a, b)),
318 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
319 (('umin', ('umin', a, b), b), ('umin', a, b)),
320 (('imin', ('imin', a, b), b), ('imin', a, b)),
321 (('fmax', a, ('fneg', a)), ('fabs', a)),
322 (('imax', a, ('ineg', a)), ('iabs', a)),
323 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
324 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
325 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
326 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
327 (('fmin', a, ('fabs', a)), a),
328 (('imin', a, ('iabs', a)), a),
329 (('fmax', a, ('fneg', ('fabs', a))), a),
330 (('imax', a, ('ineg', ('iabs', a))), a),
331 (('fmax', a, ('fabs', a)), ('fabs', a)),
332 (('imax', a, ('iabs', a)), ('iabs', a)),
333 (('fmax', a, ('fneg', a)), ('fabs', a)),
334 (('imax', a, ('ineg', a)), ('iabs', a)),
335 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
336 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
337 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
338 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
339 (('fsat', ('fsat', a)), ('fsat', a)),
340 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
341 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
342 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
343 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
344 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
345 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
346 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
347 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
348 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
349 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
350 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
351 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
352 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
353 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
354 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
355 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
356 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
357 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
358 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
359 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
360 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
361 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
362
363 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
364 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
365 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
366 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
367 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
368 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
369 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
370 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
371 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
372 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
373 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
374 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
375 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
376 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
377 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
378 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
379
380 (('ior', 'a@bool', ('ieq', a, False)), True),
381 (('ior', a, ('inot', a)), -1),
382
383 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
384
385 # These patterns can result when (a < b || a < c) => (a < min(b, c))
386 # transformations occur before constant propagation and loop-unrolling.
387 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
388 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
389 (('~fge', a, ('fmin', b, a)), True),
390 (('~fge', ('fmax', a, b), a), True),
391 (('~flt', a, ('fmin', b, a)), False),
392 (('~flt', ('fmax', a, b), a), False),
393 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
394 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
395
396 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
397 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
398 (('ige', a, ('imin', b, a)), True),
399 (('ige', ('imax', a, b), a), True),
400 (('ult', a, ('umax', b, a)), ('ult', a, b)),
401 (('ult', ('umin', a, b), a), ('ult', b, a)),
402 (('uge', a, ('umin', b, a)), True),
403 (('uge', ('umax', a, b), a), True),
404 (('ilt', a, ('imin', b, a)), False),
405 (('ilt', ('imax', a, b), a), False),
406 (('ige', a, ('imax', b, a)), ('ige', a, b)),
407 (('ige', ('imin', a, b), a), ('ige', b, a)),
408 (('ult', a, ('umin', b, a)), False),
409 (('ult', ('umax', a, b), a), False),
410 (('uge', a, ('umax', b, a)), ('uge', a, b)),
411 (('uge', ('umin', a, b), a), ('uge', b, a)),
412
413 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
414 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
415 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
416 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
417 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
418 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
419 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
420 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
421 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
422 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
423 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
424 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
425 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
426 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
427 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
428 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
429
430 (('fabs', ('slt', a, b)), ('slt', a, b)),
431 (('fabs', ('sge', a, b)), ('sge', a, b)),
432 (('fabs', ('seq', a, b)), ('seq', a, b)),
433 (('fabs', ('sne', a, b)), ('sne', a, b)),
434 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
435 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
436 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
437 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
438 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
439 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
440 # Emulating booleans
441 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
442 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
443 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
444 (('iand', 'a@bool32', 1.0), ('b2f', a)),
445 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
446 (('ineg', ('b2i32', 'a@32')), a),
447 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
448 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
449 # Comparison with the same args. Note that these are not done for
450 # the float versions because NaN always returns false on float
451 # inequalities.
452 (('ilt', a, a), False),
453 (('ige', a, a), True),
454 (('ieq', a, a), True),
455 (('ine', a, a), False),
456 (('ult', a, a), False),
457 (('uge', a, a), True),
458 # Logical and bit operations
459 (('fand', a, 0.0), 0.0),
460 (('iand', a, a), a),
461 (('iand', a, ~0), a),
462 (('iand', a, 0), 0),
463 (('ior', a, a), a),
464 (('ior', a, 0), a),
465 (('ior', a, True), True),
466 (('fxor', a, a), 0.0),
467 (('ixor', a, a), 0),
468 (('ixor', a, 0), a),
469 (('inot', ('inot', a)), a),
470 (('ior', ('iand', a, b), b), b),
471 (('ior', ('ior', a, b), b), ('ior', a, b)),
472 (('iand', ('ior', a, b), b), b),
473 (('iand', ('iand', a, b), b), ('iand', a, b)),
474 # DeMorgan's Laws
475 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
476 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
477 # Shift optimizations
478 (('ishl', 0, a), 0),
479 (('ishl', a, 0), a),
480 (('ishr', 0, a), 0),
481 (('ishr', a, 0), a),
482 (('ushr', 0, a), 0),
483 (('ushr', a, 0), a),
484 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
485 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
486 # Exponential/logarithmic identities
487 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
488 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
489 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
490 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
491 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
492 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
493 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
494 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
495 (('~fpow', a, 1.0), a),
496 (('~fpow', a, 2.0), ('fmul', a, a)),
497 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
498 (('~fpow', 2.0, a), ('fexp2', a)),
499 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
500 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
501 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
502 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
503 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
504 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
505 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
506 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
507 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
508 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
509 # Division and reciprocal
510 (('~fdiv', 1.0, a), ('frcp', a)),
511 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
512 (('~frcp', ('frcp', a)), a),
513 (('~frcp', ('fsqrt', a)), ('frsq', a)),
514 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
515 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
516 # Boolean simplifications
517 (('ieq', 'a@bool', True), a),
518 (('ine(is_not_used_by_if)', 'a@bool', True), ('inot', a)),
519 (('ine', 'a@bool', False), a),
520 (('ieq(is_not_used_by_if)', 'a@bool', False), ('inot', 'a')),
521 (('bcsel', a, True, False), a),
522 (('bcsel', a, False, True), ('inot', a)),
523 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
524 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
525 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
526 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
527 (('bcsel', True, b, c), b),
528 (('bcsel', False, b, c), c),
529 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
530 # The result of this should be hit by constant propagation and, in the
531 # next round of opt_algebraic, get picked up by one of the above two.
532 (('bcsel', '#a', b, c), ('bcsel', ('ine', 'a', 0), b, c)),
533
534 (('bcsel', a, b, b), b),
535 (('fcsel', a, b, b), b),
536
537 # D3D Boolean emulation
538 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
539 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
540 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
541 ('ineg', ('b2i', ('iand', a, b)))),
542 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
543 ('ineg', ('b2i', ('ior', a, b)))),
544 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
545 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
546 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
547 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
548 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
549
550 # Conversions
551 (('i2b32', ('b2i', 'a@32')), a),
552 (('f2i', ('ftrunc', a)), ('f2i', a)),
553 (('f2u', ('ftrunc', a)), ('f2u', a)),
554 (('i2b', ('ineg', a)), ('i2b', a)),
555 (('i2b', ('iabs', a)), ('i2b', a)),
556 (('fabs', ('b2f', a)), ('b2f', a)),
557 (('iabs', ('b2i', a)), ('b2i', a)),
558 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
559
560 # Ironically, mark these as imprecise because removing the conversions may
561 # preserve more precision than doing the conversions (e.g.,
562 # uint(float(0x81818181u)) == 0x81818200).
563 (('~f2i32', ('i2f', 'a@32')), a),
564 (('~f2i32', ('u2f', 'a@32')), a),
565 (('~f2u32', ('i2f', 'a@32')), a),
566 (('~f2u32', ('u2f', 'a@32')), a),
567
568 # Packing and then unpacking does nothing
569 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
570 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
571 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
572 ('unpack_64_2x32_split_y', a)), a),
573
574 # Byte extraction
575 (('ushr', ('ishl', 'a@32', 24), 24), ('extract_u8', a, 0), '!options->lower_extract_byte'),
576 (('ushr', ('ishl', 'a@32', 16), 24), ('extract_u8', a, 1), '!options->lower_extract_byte'),
577 (('ushr', ('ishl', 'a@32', 8), 24), ('extract_u8', a, 2), '!options->lower_extract_byte'),
578 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
579 (('ishr', ('ishl', 'a@32', 24), 24), ('extract_i8', a, 0), '!options->lower_extract_byte'),
580 (('ishr', ('ishl', 'a@32', 16), 24), ('extract_i8', a, 1), '!options->lower_extract_byte'),
581 (('ishr', ('ishl', 'a@32', 8), 24), ('extract_i8', a, 2), '!options->lower_extract_byte'),
582 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
583 (('iand', 0xff, ('ushr', a, 16)), ('extract_u8', a, 2), '!options->lower_extract_byte'),
584 (('iand', 0xff, ('ushr', a, 8)), ('extract_u8', a, 1), '!options->lower_extract_byte'),
585 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte'),
586
587 # Word extraction
588 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
589 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
590 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
591 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
592 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
593
594 # Subtracts
595 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
596 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
597 (('ussub_4x8', a, 0), a),
598 (('ussub_4x8', a, ~0), 0),
599 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
600 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
601 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
602 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
603 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
604 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
605 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
606 (('iabs', ('isub', 0, a)), ('iabs', a)),
607
608 # Propagate negation up multiplication chains
609 (('fmul', ('fneg', a), b), ('fneg', ('fmul', a, b))),
610 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
611
612 # Propagate constants up multiplication chains
613 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
614 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
615 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
616 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
617
618 # Reassociate constants in add/mul chains so they can be folded together.
619 # For now, we mostly only handle cases where the constants are separated by
620 # a single non-constant. We could do better eventually.
621 (('~fmul', '#a', ('fmul', b, '#c')), ('fmul', ('fmul', a, c), b)),
622 (('imul', '#a', ('imul', b, '#c')), ('imul', ('imul', a, c), b)),
623 (('~fadd', '#a', ('fadd', b, '#c')), ('fadd', ('fadd', a, c), b)),
624 (('~fadd', '#a', ('fneg', ('fadd', b, '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
625 (('iadd', '#a', ('iadd', b, '#c')), ('iadd', ('iadd', a, c), b)),
626
627 # By definition...
628 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
629 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
630 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
631
632 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
633 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
634 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
635
636 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
637
638 # Misc. lowering
639 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod32'),
640 (('fmod@64', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod64'),
641 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod32'),
642 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
643 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
644
645 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
646 ('bcsel', ('ilt', 31, 'bits'), 'insert',
647 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
648 'options->lower_bitfield_insert'),
649
650 # Alternative lowering that doesn't rely on bfi.
651 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
652 ('bcsel', ('ilt', 31, 'bits'),
653 'insert',
654 ('ior',
655 ('iand', 'base', ('inot', ('bfm', 'bits', 'offset'))),
656 ('iand', ('ishl', 'insert', 'offset'), ('bfm', 'bits', 'offset')))),
657 'options->lower_bitfield_insert_to_shifts'),
658
659 # bfm lowering -- note that the NIR opcode is undefined if either arg is 32.
660 (('bfm', 'bits', 'offset'),
661 ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'),
662 'options->lower_bfm'),
663
664 (('ibitfield_extract', 'value', 'offset', 'bits'),
665 ('bcsel', ('ilt', 31, 'bits'), 'value',
666 ('ibfe', 'value', 'offset', 'bits')),
667 'options->lower_bitfield_extract'),
668
669 (('ubitfield_extract', 'value', 'offset', 'bits'),
670 ('bcsel', ('ult', 31, 'bits'), 'value',
671 ('ubfe', 'value', 'offset', 'bits')),
672 'options->lower_bitfield_extract'),
673
674 (('ibitfield_extract', 'value', 'offset', 'bits'),
675 ('bcsel', ('ieq', 0, 'bits'),
676 0,
677 ('ishr',
678 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
679 ('isub', 32, 'bits'))),
680 'options->lower_bitfield_extract_to_shifts'),
681
682 (('ubitfield_extract', 'value', 'offset', 'bits'),
683 ('iand',
684 ('ushr', 'value', 'offset'),
685 ('bcsel', ('ieq', 'bits', 32),
686 0xffffffff,
687 ('bfm', 'bits', 0))),
688 'options->lower_bitfield_extract_to_shifts'),
689
690 (('ifind_msb', 'value'),
691 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
692 'options->lower_ifind_msb'),
693
694 (('find_lsb', 'value'),
695 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
696 'options->lower_find_lsb'),
697
698 (('extract_i8', a, 'b@32'),
699 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
700 'options->lower_extract_byte'),
701
702 (('extract_u8', a, 'b@32'),
703 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
704 'options->lower_extract_byte'),
705
706 (('extract_i16', a, 'b@32'),
707 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
708 'options->lower_extract_word'),
709
710 (('extract_u16', a, 'b@32'),
711 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
712 'options->lower_extract_word'),
713
714 (('pack_unorm_2x16', 'v'),
715 ('pack_uvec2_to_uint',
716 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
717 'options->lower_pack_unorm_2x16'),
718
719 (('pack_unorm_4x8', 'v'),
720 ('pack_uvec4_to_uint',
721 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
722 'options->lower_pack_unorm_4x8'),
723
724 (('pack_snorm_2x16', 'v'),
725 ('pack_uvec2_to_uint',
726 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
727 'options->lower_pack_snorm_2x16'),
728
729 (('pack_snorm_4x8', 'v'),
730 ('pack_uvec4_to_uint',
731 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
732 'options->lower_pack_snorm_4x8'),
733
734 (('unpack_unorm_2x16', 'v'),
735 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
736 ('extract_u16', 'v', 1))),
737 65535.0),
738 'options->lower_unpack_unorm_2x16'),
739
740 (('unpack_unorm_4x8', 'v'),
741 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
742 ('extract_u8', 'v', 1),
743 ('extract_u8', 'v', 2),
744 ('extract_u8', 'v', 3))),
745 255.0),
746 'options->lower_unpack_unorm_4x8'),
747
748 (('unpack_snorm_2x16', 'v'),
749 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
750 ('extract_i16', 'v', 1))),
751 32767.0))),
752 'options->lower_unpack_snorm_2x16'),
753
754 (('unpack_snorm_4x8', 'v'),
755 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
756 ('extract_i8', 'v', 1),
757 ('extract_i8', 'v', 2),
758 ('extract_i8', 'v', 3))),
759 127.0))),
760 'options->lower_unpack_snorm_4x8'),
761
762 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
763 ]
764
765 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
766
767 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
768 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
769 ('iand', (invert[left], a, b), (invert[right], c, d))))
770 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
771 ('ior', (invert[left], a, b), (invert[right], c, d))))
772
773 # Optimize x2bN(b2x(x)) -> x
774 for size in type_sizes('bool'):
775 aN = 'a@' + str(size)
776 f2bN = 'f2b' + str(size)
777 i2bN = 'i2b' + str(size)
778 optimizations.append(((f2bN, ('b2f', aN)), a))
779 optimizations.append(((i2bN, ('b2i', aN)), a))
780
781 # Optimize x2yN(b2x(x)) -> b2y
782 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
783 if x != 'f' and y != 'f' and x != y:
784 continue
785
786 b2x = 'b2f' if x == 'f' else 'b2i'
787 b2y = 'b2f' if y == 'f' else 'b2i'
788 x2yN = '{}2{}'.format(x, y)
789 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
790
791 def fexp2i(exp, bits):
792 # We assume that exp is already in the right range.
793 if bits == 32:
794 return ('ishl', ('iadd', exp, 127), 23)
795 elif bits == 64:
796 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
797 else:
798 assert False
799
800 def ldexp(f, exp, bits):
801 # First, we clamp exp to a reasonable range. The maximum possible range
802 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
803 # a maximum range of [-149, 127]. This means that we can potentially have
804 # a swing of +-276. If you start with FLT_MAX, you actually have to do
805 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
806 # spec, on the other hand, only requires that we handle an exponent value
807 # in the range [-126, 128]. This implementation is *mostly* correct; it
808 # handles a range on exp of [-252, 254] which allows you to create any
809 # value (including denorms if the hardware supports it) and to adjust the
810 # exponent of any normal value to anything you want.
811 if bits == 32:
812 exp = ('imin', ('imax', exp, -252), 254)
813 elif bits == 64:
814 exp = ('imin', ('imax', exp, -2044), 2046)
815 else:
816 assert False
817
818 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
819 # (We use ishr which isn't the same for -1, but the -1 case still works
820 # since we use exp-exp/2 as the second exponent.) While the spec
821 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
822 # work with denormals and doesn't allow for the full swing in exponents
823 # that you can get with normalized values. Instead, we create two powers
824 # of two and multiply by them each in turn. That way the effective range
825 # of our exponent is doubled.
826 pow2_1 = fexp2i(('ishr', exp, 1), bits)
827 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
828 return ('fmul', ('fmul', f, pow2_1), pow2_2)
829
830 optimizations += [
831 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
832 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
833 ]
834
835 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
836 def bitfield_reverse(u):
837 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
838 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
839 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
840 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
841 step5 = ('ior', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
842
843 return step5
844
845 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
846
847 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
848 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
849 # and, if a is a NaN then the second comparison will fail anyway.
850 for op in ['flt', 'fge', 'feq']:
851 optimizations += [
852 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
853 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
854 ]
855
856 # Add optimizations to handle the case where the result of a ternary is
857 # compared to a constant. This way we can take things like
858 #
859 # (a ? 0 : 1) > 0
860 #
861 # and turn it into
862 #
863 # a ? (0 > 0) : (1 > 0)
864 #
865 # which constant folding will eat for lunch. The resulting ternary will
866 # further get cleaned up by the boolean reductions above and we will be
867 # left with just the original variable "a".
868 for op in ['flt', 'fge', 'feq', 'fne',
869 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
870 optimizations += [
871 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
872 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
873 ((op, '#d', ('bcsel', a, '#b', '#c')),
874 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
875 ]
876
877
878 # For example, this converts things like
879 #
880 # 1 + mix(0, a - 1, condition)
881 #
882 # into
883 #
884 # mix(1, (a-1)+1, condition)
885 #
886 # Other optimizations will rearrange the constants.
887 for op in ['fadd', 'fmul', 'iadd', 'imul']:
888 optimizations += [
889 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
890 ]
891
892 # This section contains "late" optimizations that should be run before
893 # creating ffmas and calling regular optimizations for the final time.
894 # Optimizations should go here if they help code generation and conflict
895 # with the regular optimizations.
896 before_ffma_optimizations = [
897 # Propagate constants down multiplication chains
898 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
899 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
900 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
901 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
902
903 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
904 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
905 (('~fadd', ('fneg', a), a), 0.0),
906 (('iadd', ('ineg', a), a), 0),
907 (('iadd', ('ineg', a), ('iadd', a, b)), b),
908 (('iadd', a, ('iadd', ('ineg', a), b)), b),
909 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
910 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
911 ]
912
913 # This section contains "late" optimizations that should be run after the
914 # regular optimizations have finished. Optimizations should go here if
915 # they help code generation but do not necessarily produce code that is
916 # more easily optimizable.
917 late_optimizations = [
918 # Most of these optimizations aren't quite safe when you get infinity or
919 # Nan involved but the first one should be fine.
920 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
921 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
922 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
923 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
924 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
925 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
926
927 (('~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)))),
928
929 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
930 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
931 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
932 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
933
934 (('b2f(is_used_more_than_once)', ('inot', 'a@1')), ('bcsel', a, 0.0, 1.0)),
935 (('fneg(is_used_more_than_once)', ('b2f', ('inot', 'a@1'))), ('bcsel', a, -0.0, -1.0)),
936
937 # we do these late so that we don't get in the way of creating ffmas
938 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
939 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
940 ]
941
942 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
943 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
944 before_ffma_optimizations).render())
945 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
946 late_optimizations).render())