nir/algebraic: Fix up extract_[iu]8 after loop unrolling
[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 (('unpack_64_2x32_split_x', ('imul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
74 (('unpack_64_2x32_split_x', ('umul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
75 (('imul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('imul_high', a, b)), 'options->lower_mul_2x32_64'),
76 (('umul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('umul_high', a, b)), 'options->lower_mul_2x32_64'),
77 (('udiv', a, 1), a),
78 (('idiv', a, 1), a),
79 (('umod', a, 1), 0),
80 (('imod', a, 1), 0),
81 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b))),
82 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
83 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
84 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
85
86 (('fneg', ('fneg', a)), a),
87 (('ineg', ('ineg', a)), a),
88 (('fabs', ('fabs', a)), ('fabs', a)),
89 (('fabs', ('fneg', a)), ('fabs', a)),
90 (('fabs', ('u2f', a)), ('u2f', a)),
91 (('iabs', ('iabs', a)), ('iabs', a)),
92 (('iabs', ('ineg', a)), ('iabs', a)),
93 (('f2b', ('fneg', a)), ('f2b', a)),
94 (('i2b', ('ineg', a)), ('i2b', a)),
95 (('~fadd', a, 0.0), a),
96 (('iadd', a, 0), a),
97 (('usadd_4x8', a, 0), a),
98 (('usadd_4x8', a, ~0), ~0),
99 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
100 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
101 (('~fadd', ('fneg', a), a), 0.0),
102 (('iadd', ('ineg', a), a), 0),
103 (('iadd', ('ineg', a), ('iadd', a, b)), b),
104 (('iadd', a, ('iadd', ('ineg', a), b)), b),
105 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
106 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
107 (('~fmul', a, 0.0), 0.0),
108 (('imul', a, 0), 0),
109 (('umul_unorm_4x8', a, 0), 0),
110 (('umul_unorm_4x8', a, ~0), a),
111 (('fmul', a, 1.0), a),
112 (('imul', a, 1), a),
113 (('fmul', a, -1.0), ('fneg', a)),
114 (('imul', a, -1), ('ineg', a)),
115 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
116 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
117 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
118 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
119 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
120 (('~ffma', 0.0, a, b), b),
121 (('~ffma', a, 0.0, b), b),
122 (('~ffma', a, b, 0.0), ('fmul', a, b)),
123 (('ffma', a, 1.0, b), ('fadd', a, b)),
124 (('ffma', 1.0, a, b), ('fadd', a, b)),
125 (('~flrp', a, b, 0.0), a),
126 (('~flrp', a, b, 1.0), b),
127 (('~flrp', a, a, b), a),
128 (('~flrp', 0.0, a, b), ('fmul', a, b)),
129 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
130 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
131 (('flrp@16', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp16'),
132 (('flrp@32', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp32'),
133 (('flrp@64', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp64'),
134 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
135 (('fadd', a, ('fneg', ('ffract', a))), ('ffloor', a), '!options->lower_ffloor'),
136 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
137 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
138 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
139 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ))), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
140 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ))), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
141 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
142 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
143 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
144 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
145 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
146
147 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d)),
148 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
149 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
150 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
151
152 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
153 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
154
155 # (a * #b + #c) << #d
156 # ((a * #b) << #d) + (#c << #d)
157 # (a * (#b << #d)) + (#c << #d)
158 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
159 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
160
161 # (a * #b) << #c
162 # a * (#b << #c)
163 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
164
165 # Comparison simplifications
166 (('~inot', ('flt', a, b)), ('fge', a, b)),
167 (('~inot', ('fge', a, b)), ('flt', a, b)),
168 (('~inot', ('feq', a, b)), ('fne', a, b)),
169 (('~inot', ('fne', a, b)), ('feq', a, b)),
170 (('inot', ('ilt', a, b)), ('ige', a, b)),
171 (('inot', ('ult', a, b)), ('uge', a, b)),
172 (('inot', ('ige', a, b)), ('ilt', a, b)),
173 (('inot', ('uge', a, b)), ('ult', a, b)),
174 (('inot', ('ieq', a, b)), ('ine', a, b)),
175 (('inot', ('ine', a, b)), ('ieq', a, b)),
176
177 # 0.0 >= b2f(a)
178 # b2f(a) <= 0.0
179 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
180 # inot(a)
181 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
182
183 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
184
185 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
186 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
187 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
188 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
189 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
190 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
191 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
192 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
193 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
194 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
195 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
196 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
197 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
198 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
199 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
200 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
201 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
202 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
203 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
204 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
205
206 # -(b2f(a) + b2f(b)) < 0
207 # 0 < b2f(a) + b2f(b)
208 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
209 # a || b
210 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
211 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
212
213 # -(b2f(a) + b2f(b)) >= 0
214 # 0 >= b2f(a) + b2f(b)
215 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
216 # !(a || b)
217 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
218 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
219
220 # Some optimizations (below) convert things like (a < b || c < b) into
221 # (min(a, c) < b). However, this interfers with the previous optimizations
222 # that try to remove comparisons with negated sums of b2f. This just
223 # breaks that apart.
224 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
225 ('ior', ('flt', c, 0.0), ('ior', a, b))),
226
227 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
228 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
229 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
230 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
231
232 # Cannot remove the addition from ilt or ige due to overflow.
233 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
234 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
235
236 # fmin(-b2f(a), b) >= 0.0
237 # -b2f(a) >= 0.0 && b >= 0.0
238 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
239 # b2f(a) == 0.0 && b >= 0.0
240 # a == False && b >= 0.0
241 # !a && b >= 0.0
242 #
243 # The fge in the second replacement is not a typo. I leave the proof that
244 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
245 # reader.
246 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
247 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
248
249 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
250 (('fne', ('b2f', 'a@1'), 0.0), a),
251 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
252 (('ine', ('b2i', 'a@1'), 0), a),
253
254 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
255 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
256 (('fge', ('u2f', a), 0.0), True),
257 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
258 (('flt', ('u2f', a), 0.0), False),
259 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
260 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
261 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
262 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
263 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
264 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
265 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
266
267 # 0.0 < fabs(a)
268 # fabs(a) > 0.0
269 # fabs(a) != 0.0 because fabs(a) must be >= 0
270 # a != 0.0
271 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
272
273 # -fabs(a) < 0.0
274 # fabs(a) > 0.0
275 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
276
277 # 0.0 >= fabs(a)
278 # 0.0 == fabs(a) because fabs(a) must be >= 0
279 # 0.0 == a
280 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
281
282 # -fabs(a) >= 0.0
283 # 0.0 >= fabs(a)
284 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
285
286 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
287 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
288 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
289 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
290
291 # fmin(b2f(a), b)
292 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
293 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
294 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
295 #
296 # Since b is a constant, constant folding will eliminate the fmin and the
297 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
298 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
299
300 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
301
302 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
303 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
304 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
305 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
306 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
307 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
308 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
309 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
310 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
311 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
312 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
313 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
314 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
315 (('bcsel', a, True, 'b@bool'), ('ior', a, b)),
316 (('fmin', a, a), a),
317 (('fmax', a, a), a),
318 (('imin', a, a), a),
319 (('imax', a, a), a),
320 (('umin', a, a), a),
321 (('umax', a, a), a),
322 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
323 (('umax', ('umax', a, b), b), ('umax', a, b)),
324 (('imax', ('imax', a, b), b), ('imax', a, b)),
325 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
326 (('umin', ('umin', a, b), b), ('umin', a, b)),
327 (('imin', ('imin', a, b), b), ('imin', a, b)),
328 (('fmax', a, ('fneg', a)), ('fabs', a)),
329 (('imax', a, ('ineg', a)), ('iabs', a)),
330 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
331 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
332 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
333 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
334 (('fmin', a, ('fabs', a)), a),
335 (('imin', a, ('iabs', a)), a),
336 (('fmax', a, ('fneg', ('fabs', a))), a),
337 (('imax', a, ('ineg', ('iabs', a))), a),
338 (('fmax', a, ('fabs', a)), ('fabs', a)),
339 (('imax', a, ('iabs', a)), ('iabs', a)),
340 (('fmax', a, ('fneg', a)), ('fabs', a)),
341 (('imax', a, ('ineg', a)), ('iabs', a)),
342 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
343 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
344 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
345 (('fsat', ('b2f', a)), ('b2f', a)),
346 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
347 (('fsat', ('fsat', a)), ('fsat', a)),
348 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
349 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
350 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
351 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
352 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
353 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
354 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
355 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
356 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
357 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
358 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
359 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
360 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
361 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
362 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
363 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
364 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
365 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
366 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
367 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
368 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
369 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
370
371 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
372 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
373 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
374 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
375 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
376 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
377 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
378 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
379 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
380 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
381 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
382 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
383 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
384 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
385 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
386 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
387
388 # Common pattern like 'if (i == 0 || i == 1 || ...)'
389 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
390 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
391 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
392
393 (('ior', 'a@bool', ('ieq', a, False)), True),
394 (('ior', a, ('inot', a)), -1),
395
396 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
397
398 # These patterns can result when (a < b || a < c) => (a < min(b, c))
399 # transformations occur before constant propagation and loop-unrolling.
400 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
401 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
402 (('~fge', a, ('fmin', b, a)), True),
403 (('~fge', ('fmax', a, b), a), True),
404 (('~flt', a, ('fmin', b, a)), False),
405 (('~flt', ('fmax', a, b), a), False),
406 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
407 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
408
409 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
410 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
411 (('ige', a, ('imin', b, a)), True),
412 (('ige', ('imax', a, b), a), True),
413 (('ult', a, ('umax', b, a)), ('ult', a, b)),
414 (('ult', ('umin', a, b), a), ('ult', b, a)),
415 (('uge', a, ('umin', b, a)), True),
416 (('uge', ('umax', a, b), a), True),
417 (('ilt', a, ('imin', b, a)), False),
418 (('ilt', ('imax', a, b), a), False),
419 (('ige', a, ('imax', b, a)), ('ige', a, b)),
420 (('ige', ('imin', a, b), a), ('ige', b, a)),
421 (('ult', a, ('umin', b, a)), False),
422 (('ult', ('umax', a, b), a), False),
423 (('uge', a, ('umax', b, a)), ('uge', a, b)),
424 (('uge', ('umin', a, b), a), ('uge', b, a)),
425
426 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
427 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
428 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
429 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
430 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
431 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
432 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
433 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
434 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
435 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
436 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
437 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
438 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
439 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
440 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
441 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
442
443 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
444 # negative.
445 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
446 ('iabs', ('ishr', a, b))),
447 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
448
449 (('fabs', ('slt', a, b)), ('slt', a, b)),
450 (('fabs', ('sge', a, b)), ('sge', a, b)),
451 (('fabs', ('seq', a, b)), ('seq', a, b)),
452 (('fabs', ('sne', a, b)), ('sne', a, b)),
453 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
454 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
455 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
456 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
457 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
458 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
459 # Emulating booleans
460 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
461 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
462 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
463 (('iand', 'a@bool32', 1.0), ('b2f', a)),
464 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
465 (('ineg', ('b2i32', 'a@32')), a),
466 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
467 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
468 # Comparison with the same args. Note that these are not done for
469 # the float versions because NaN always returns false on float
470 # inequalities.
471 (('ilt', a, a), False),
472 (('ige', a, a), True),
473 (('ieq', a, a), True),
474 (('ine', a, a), False),
475 (('ult', a, a), False),
476 (('uge', a, a), True),
477 # Logical and bit operations
478 (('fand', a, 0.0), 0.0),
479 (('iand', a, a), a),
480 (('iand', a, ~0), a),
481 (('iand', a, 0), 0),
482 (('ior', a, a), a),
483 (('ior', a, 0), a),
484 (('ior', a, True), True),
485 (('fxor', a, a), 0.0),
486 (('ixor', a, a), 0),
487 (('ixor', a, 0), a),
488 (('inot', ('inot', a)), a),
489 (('ior', ('iand', a, b), b), b),
490 (('ior', ('ior', a, b), b), ('ior', a, b)),
491 (('iand', ('ior', a, b), b), b),
492 (('iand', ('iand', a, b), b), ('iand', a, b)),
493 # DeMorgan's Laws
494 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
495 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
496 # Shift optimizations
497 (('ishl', 0, a), 0),
498 (('ishl', a, 0), a),
499 (('ishr', 0, a), 0),
500 (('ishr', a, 0), a),
501 (('ushr', 0, a), 0),
502 (('ushr', a, 0), a),
503 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
504 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
505 # Exponential/logarithmic identities
506 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
507 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
508 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
509 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
510 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
511 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
512 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
513 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
514 (('~fpow', a, 1.0), a),
515 (('~fpow', a, 2.0), ('fmul', a, a)),
516 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
517 (('~fpow', 2.0, a), ('fexp2', a)),
518 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
519 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
520 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
521 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
522 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
523 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
524 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
525 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
526 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
527 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
528 # Division and reciprocal
529 (('~fdiv', 1.0, a), ('frcp', a)),
530 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
531 (('~frcp', ('frcp', a)), a),
532 (('~frcp', ('fsqrt', a)), ('frsq', a)),
533 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
534 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
535 # Boolean simplifications
536 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
537 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
538 (('ieq', 'a@bool', True), a),
539 (('ine(is_not_used_by_if)', 'a@bool', True), ('inot', a)),
540 (('ine', 'a@bool', False), a),
541 (('ieq(is_not_used_by_if)', 'a@bool', False), ('inot', 'a')),
542 (('bcsel', a, True, False), a),
543 (('bcsel', a, False, True), ('inot', a)),
544 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
545 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
546 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
547 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
548 (('bcsel', True, b, c), b),
549 (('bcsel', False, b, c), c),
550 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
551 # The result of this should be hit by constant propagation and, in the
552 # next round of opt_algebraic, get picked up by one of the above two.
553 (('bcsel', '#a', b, c), ('bcsel', ('ine', 'a', 0), b, c)),
554
555 (('bcsel', a, b, b), b),
556 (('fcsel', a, b, b), b),
557
558 # D3D Boolean emulation
559 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
560 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
561 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
562 ('ineg', ('b2i', ('iand', a, b)))),
563 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
564 ('ineg', ('b2i', ('ior', a, b)))),
565 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
566 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
567 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
568 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
569 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
570
571 # SM5 32-bit shifts are defined to use the 5 least significant bits
572 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
573 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
574 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
575
576 # Conversions
577 (('i2b32', ('b2i', 'a@32')), a),
578 (('f2i', ('ftrunc', a)), ('f2i', a)),
579 (('f2u', ('ftrunc', a)), ('f2u', a)),
580 (('i2b', ('ineg', a)), ('i2b', a)),
581 (('i2b', ('iabs', a)), ('i2b', a)),
582 (('fabs', ('b2f', a)), ('b2f', a)),
583 (('iabs', ('b2i', a)), ('b2i', a)),
584 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
585
586 # Ironically, mark these as imprecise because removing the conversions may
587 # preserve more precision than doing the conversions (e.g.,
588 # uint(float(0x81818181u)) == 0x81818200).
589 (('~f2i32', ('i2f', 'a@32')), a),
590 (('~f2i32', ('u2f', 'a@32')), a),
591 (('~f2u32', ('i2f', 'a@32')), a),
592 (('~f2u32', ('u2f', 'a@32')), a),
593
594 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
595 # says:
596 #
597 # It is undefined to convert a negative floating-point value to an
598 # uint.
599 #
600 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
601 # some optimizations in the i965 backend to proceed.
602 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
603 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
604 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
605 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
606
607 # Packing and then unpacking does nothing
608 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
609 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
610 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
611 ('unpack_64_2x32_split_y', a)), a),
612
613 # Byte extraction
614 (('ushr', ('ishl', 'a@32', 24), 24), ('extract_u8', a, 0), '!options->lower_extract_byte'),
615 (('ushr', ('ishl', 'a@32', 16), 24), ('extract_u8', a, 1), '!options->lower_extract_byte'),
616 (('ushr', ('ishl', 'a@32', 8), 24), ('extract_u8', a, 2), '!options->lower_extract_byte'),
617 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
618 (('ishr', ('ishl', 'a@32', 24), 24), ('extract_i8', a, 0), '!options->lower_extract_byte'),
619 (('ishr', ('ishl', 'a@32', 16), 24), ('extract_i8', a, 1), '!options->lower_extract_byte'),
620 (('ishr', ('ishl', 'a@32', 8), 24), ('extract_i8', a, 2), '!options->lower_extract_byte'),
621 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
622 (('iand', 0xff, ('ushr', a, 16)), ('extract_u8', a, 2), '!options->lower_extract_byte'),
623 (('iand', 0xff, ('ushr', a, 8)), ('extract_u8', a, 1), '!options->lower_extract_byte'),
624 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
625 ]
626
627 # The ('extract_u8', a, 0) pattern, above, can trigger in cases where the
628 # shift count is based on a loop induction variable. Once the loop is
629 # unrolled, constant folding will generate patterns like those below.
630 for op in ('ushr', 'ishr'):
631 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
632 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
633 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
634
635 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
636
637 # The ('extract_[iu]8', a, 3) patterns, above, can trigger in cases where the
638 # shift count is based on a loop induction variable. Once the loop is
639 # unrolled, constant folding will generate patterns like those below.
640 for op in ('extract_u8', 'extract_i8'):
641 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
642
643 optimizations.extend([
644 # Word extraction
645 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
646 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
647 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
648 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
649 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
650
651 # Subtracts
652 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
653 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
654 (('ussub_4x8', a, 0), a),
655 (('ussub_4x8', a, ~0), 0),
656 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
657 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
658 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
659 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
660 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
661 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
662 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
663 (('iabs', ('isub', 0, a)), ('iabs', a)),
664
665 # Propagate negation up multiplication chains
666 (('fmul', ('fneg', a), b), ('fneg', ('fmul', a, b))),
667 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
668
669 # Propagate constants up multiplication chains
670 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
671 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
672 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
673 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
674
675 # Reassociate constants in add/mul chains so they can be folded together.
676 # For now, we mostly only handle cases where the constants are separated by
677 # a single non-constant. We could do better eventually.
678 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
679 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
680 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
681 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
682 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
683
684 # By definition...
685 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
686 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
687 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
688
689 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
690 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
691 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
692
693 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
694
695 # Misc. lowering
696 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod16'),
697 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod32'),
698 (('fmod@64', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod64'),
699 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod32'),
700 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
701 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
702
703 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
704 ('bcsel', ('ilt', 31, 'bits'), 'insert',
705 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
706 'options->lower_bitfield_insert'),
707 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
708 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
709 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
710 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
711 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
712 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
713
714 # Alternative lowering that doesn't rely on bfi.
715 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
716 ('bcsel', ('ilt', 31, 'bits'),
717 'insert',
718 ('ior',
719 ('iand', 'base', ('inot', ('bfm', 'bits', 'offset'))),
720 ('iand', ('ishl', 'insert', 'offset'), ('bfm', 'bits', 'offset')))),
721 'options->lower_bitfield_insert_to_shifts'),
722
723 # bfm lowering -- note that the NIR opcode is undefined if either arg is 32.
724 (('bfm', 'bits', 'offset'),
725 ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'),
726 'options->lower_bfm'),
727
728 (('ibitfield_extract', 'value', 'offset', 'bits'),
729 ('bcsel', ('ilt', 31, 'bits'), 'value',
730 ('ibfe', 'value', 'offset', 'bits')),
731 'options->lower_bitfield_extract'),
732
733 (('ubitfield_extract', 'value', 'offset', 'bits'),
734 ('bcsel', ('ult', 31, 'bits'), 'value',
735 ('ubfe', 'value', 'offset', 'bits')),
736 'options->lower_bitfield_extract'),
737
738 (('ibitfield_extract', 'value', 'offset', 'bits'),
739 ('bcsel', ('ieq', 0, 'bits'),
740 0,
741 ('ishr',
742 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
743 ('isub', 32, 'bits'))),
744 'options->lower_bitfield_extract_to_shifts'),
745
746 (('ubitfield_extract', 'value', 'offset', 'bits'),
747 ('iand',
748 ('ushr', 'value', 'offset'),
749 ('bcsel', ('ieq', 'bits', 32),
750 0xffffffff,
751 ('bfm', 'bits', 0))),
752 'options->lower_bitfield_extract_to_shifts'),
753
754 (('ifind_msb', 'value'),
755 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
756 'options->lower_ifind_msb'),
757
758 (('find_lsb', 'value'),
759 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
760 'options->lower_find_lsb'),
761
762 (('extract_i8', a, 'b@32'),
763 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
764 'options->lower_extract_byte'),
765
766 (('extract_u8', a, 'b@32'),
767 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
768 'options->lower_extract_byte'),
769
770 (('extract_i16', a, 'b@32'),
771 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
772 'options->lower_extract_word'),
773
774 (('extract_u16', a, 'b@32'),
775 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
776 'options->lower_extract_word'),
777
778 (('pack_unorm_2x16', 'v'),
779 ('pack_uvec2_to_uint',
780 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
781 'options->lower_pack_unorm_2x16'),
782
783 (('pack_unorm_4x8', 'v'),
784 ('pack_uvec4_to_uint',
785 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
786 'options->lower_pack_unorm_4x8'),
787
788 (('pack_snorm_2x16', 'v'),
789 ('pack_uvec2_to_uint',
790 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
791 'options->lower_pack_snorm_2x16'),
792
793 (('pack_snorm_4x8', 'v'),
794 ('pack_uvec4_to_uint',
795 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
796 'options->lower_pack_snorm_4x8'),
797
798 (('unpack_unorm_2x16', 'v'),
799 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
800 ('extract_u16', 'v', 1))),
801 65535.0),
802 'options->lower_unpack_unorm_2x16'),
803
804 (('unpack_unorm_4x8', 'v'),
805 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
806 ('extract_u8', 'v', 1),
807 ('extract_u8', 'v', 2),
808 ('extract_u8', 'v', 3))),
809 255.0),
810 'options->lower_unpack_unorm_4x8'),
811
812 (('unpack_snorm_2x16', 'v'),
813 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
814 ('extract_i16', 'v', 1))),
815 32767.0))),
816 'options->lower_unpack_snorm_2x16'),
817
818 (('unpack_snorm_4x8', 'v'),
819 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
820 ('extract_i8', 'v', 1),
821 ('extract_i8', 'v', 2),
822 ('extract_i8', 'v', 3))),
823 127.0))),
824 'options->lower_unpack_snorm_4x8'),
825
826 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
827 ])
828
829 # bit_size dependent lowerings
830 for bit_size in [8, 16, 32, 64]:
831 # convenience constants
832 intmax = (1 << (bit_size - 1)) - 1
833 intmin = 1 << (bit_size - 1)
834
835 optimizations += [
836 (('iadd_sat@' + str(bit_size), a, b),
837 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
838 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
839 (('isub_sat@' + str(bit_size), a, b),
840 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
841 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
842 ]
843
844 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
845
846 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
847 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
848 ('iand', (invert[left], a, b), (invert[right], c, d))))
849 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
850 ('ior', (invert[left], a, b), (invert[right], c, d))))
851
852 # Optimize x2bN(b2x(x)) -> x
853 for size in type_sizes('bool'):
854 aN = 'a@' + str(size)
855 f2bN = 'f2b' + str(size)
856 i2bN = 'i2b' + str(size)
857 optimizations.append(((f2bN, ('b2f', aN)), a))
858 optimizations.append(((i2bN, ('b2i', aN)), a))
859
860 # Optimize x2yN(b2x(x)) -> b2y
861 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
862 if x != 'f' and y != 'f' and x != y:
863 continue
864
865 b2x = 'b2f' if x == 'f' else 'b2i'
866 b2y = 'b2f' if y == 'f' else 'b2i'
867 x2yN = '{}2{}'.format(x, y)
868 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
869
870 def fexp2i(exp, bits):
871 # We assume that exp is already in the right range.
872 if bits == 16:
873 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
874 elif bits == 32:
875 return ('ishl', ('iadd', exp, 127), 23)
876 elif bits == 64:
877 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
878 else:
879 assert False
880
881 def ldexp(f, exp, bits):
882 # First, we clamp exp to a reasonable range. The maximum possible range
883 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
884 # a maximum range of [-149, 127]. This means that we can potentially have
885 # a swing of +-276. If you start with FLT_MAX, you actually have to do
886 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
887 # spec, on the other hand, only requires that we handle an exponent value
888 # in the range [-126, 128]. This implementation is *mostly* correct; it
889 # handles a range on exp of [-252, 254] which allows you to create any
890 # value (including denorms if the hardware supports it) and to adjust the
891 # exponent of any normal value to anything you want.
892 if bits == 16:
893 exp = ('imin', ('imax', exp, -28), 30)
894 elif bits == 32:
895 exp = ('imin', ('imax', exp, -252), 254)
896 elif bits == 64:
897 exp = ('imin', ('imax', exp, -2044), 2046)
898 else:
899 assert False
900
901 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
902 # (We use ishr which isn't the same for -1, but the -1 case still works
903 # since we use exp-exp/2 as the second exponent.) While the spec
904 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
905 # work with denormals and doesn't allow for the full swing in exponents
906 # that you can get with normalized values. Instead, we create two powers
907 # of two and multiply by them each in turn. That way the effective range
908 # of our exponent is doubled.
909 pow2_1 = fexp2i(('ishr', exp, 1), bits)
910 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
911 return ('fmul', ('fmul', f, pow2_1), pow2_2)
912
913 optimizations += [
914 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
915 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
916 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
917 ]
918
919 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
920 def bitfield_reverse(u):
921 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
922 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
923 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
924 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
925 step5 = ('ior', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
926
927 return step5
928
929 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
930
931 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
932 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
933 # and, if a is a NaN then the second comparison will fail anyway.
934 for op in ['flt', 'fge', 'feq']:
935 optimizations += [
936 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
937 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
938 ]
939
940 # Add optimizations to handle the case where the result of a ternary is
941 # compared to a constant. This way we can take things like
942 #
943 # (a ? 0 : 1) > 0
944 #
945 # and turn it into
946 #
947 # a ? (0 > 0) : (1 > 0)
948 #
949 # which constant folding will eat for lunch. The resulting ternary will
950 # further get cleaned up by the boolean reductions above and we will be
951 # left with just the original variable "a".
952 for op in ['flt', 'fge', 'feq', 'fne',
953 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
954 optimizations += [
955 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
956 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
957 ((op, '#d', ('bcsel', a, '#b', '#c')),
958 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
959 ]
960
961
962 # For example, this converts things like
963 #
964 # 1 + mix(0, a - 1, condition)
965 #
966 # into
967 #
968 # mix(1, (a-1)+1, condition)
969 #
970 # Other optimizations will rearrange the constants.
971 for op in ['fadd', 'fmul', 'iadd', 'imul']:
972 optimizations += [
973 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
974 ]
975
976 # This section contains "late" optimizations that should be run before
977 # creating ffmas and calling regular optimizations for the final time.
978 # Optimizations should go here if they help code generation and conflict
979 # with the regular optimizations.
980 before_ffma_optimizations = [
981 # Propagate constants down multiplication chains
982 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
983 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
984 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
985 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
986
987 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
988 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
989 (('~fadd', ('fneg', a), a), 0.0),
990 (('iadd', ('ineg', a), a), 0),
991 (('iadd', ('ineg', a), ('iadd', a, b)), b),
992 (('iadd', a, ('iadd', ('ineg', a), b)), b),
993 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
994 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
995 ]
996
997 # This section contains "late" optimizations that should be run after the
998 # regular optimizations have finished. Optimizations should go here if
999 # they help code generation but do not necessarily produce code that is
1000 # more easily optimizable.
1001 late_optimizations = [
1002 # Most of these optimizations aren't quite safe when you get infinity or
1003 # Nan involved but the first one should be fine.
1004 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1005 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1006 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1007 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1008 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1009 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1010
1011 (('~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)))),
1012
1013 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1014 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1015 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1016 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1017
1018 (('b2f(is_used_more_than_once)', ('inot', 'a@1')), ('bcsel', a, 0.0, 1.0)),
1019 (('fneg(is_used_more_than_once)', ('b2f', ('inot', 'a@1'))), ('bcsel', a, -0.0, -1.0)),
1020
1021 # we do these late so that we don't get in the way of creating ffmas
1022 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1023 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1024
1025 (('bcsel', 'a@bool', 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1026 ]
1027
1028 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1029 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1030 before_ffma_optimizations).render())
1031 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1032 late_optimizations).render())