nir/algebraic: Add some logical OR and AND patterns
[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), ('ior', a, b)),
316 (('bcsel', a, a, b), ('ior', a, b)),
317 (('bcsel', a, b, False), ('iand', a, b)),
318 (('bcsel', a, b, a), ('iand', a, b)),
319 (('fmin', a, a), a),
320 (('fmax', a, a), a),
321 (('imin', a, a), a),
322 (('imax', a, a), a),
323 (('umin', a, a), a),
324 (('umax', a, a), a),
325 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
326 (('umax', ('umax', a, b), b), ('umax', a, b)),
327 (('imax', ('imax', a, b), b), ('imax', a, b)),
328 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
329 (('umin', ('umin', a, b), b), ('umin', a, b)),
330 (('imin', ('imin', a, b), b), ('imin', a, b)),
331 (('fmax', a, ('fneg', a)), ('fabs', a)),
332 (('imax', a, ('ineg', a)), ('iabs', a)),
333 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
334 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
335 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
336 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
337 (('fmin', a, ('fabs', a)), a),
338 (('imin', a, ('iabs', a)), a),
339 (('fmax', a, ('fneg', ('fabs', a))), a),
340 (('imax', a, ('ineg', ('iabs', a))), a),
341 (('fmax', a, ('fabs', a)), ('fabs', a)),
342 (('imax', a, ('iabs', a)), ('iabs', a)),
343 (('fmax', a, ('fneg', a)), ('fabs', a)),
344 (('imax', a, ('ineg', a)), ('iabs', a)),
345 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
346 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
347 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
348 (('fsat', ('b2f', a)), ('b2f', a)),
349 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
350 (('fsat', ('fsat', a)), ('fsat', a)),
351 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
352 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
353 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
354 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
355 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
356 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
357 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
358 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
359 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
360 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
361 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
362 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
363 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
364 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
365 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
366 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
367 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
368 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
369 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
370 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
371 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
372 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
373
374 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
375 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
376 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
377 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
378 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
379 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
380 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
381 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
382 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
383 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
384 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
385 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
386 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
387 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
388 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
389 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
390
391 # Common pattern like 'if (i == 0 || i == 1 || ...)'
392 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
393 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
394 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
395
396 (('ior', a, ('ieq', a, False)), True),
397 (('ior', a, ('inot', a)), -1),
398
399 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
400
401 # These patterns can result when (a < b || a < c) => (a < min(b, c))
402 # transformations occur before constant propagation and loop-unrolling.
403 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
404 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
405 (('~fge', a, ('fmin', b, a)), True),
406 (('~fge', ('fmax', a, b), a), True),
407 (('~flt', a, ('fmin', b, a)), False),
408 (('~flt', ('fmax', a, b), a), False),
409 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
410 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
411
412 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
413 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
414 (('ige', a, ('imin', b, a)), True),
415 (('ige', ('imax', a, b), a), True),
416 (('ult', a, ('umax', b, a)), ('ult', a, b)),
417 (('ult', ('umin', a, b), a), ('ult', b, a)),
418 (('uge', a, ('umin', b, a)), True),
419 (('uge', ('umax', a, b), a), True),
420 (('ilt', a, ('imin', b, a)), False),
421 (('ilt', ('imax', a, b), a), False),
422 (('ige', a, ('imax', b, a)), ('ige', a, b)),
423 (('ige', ('imin', a, b), a), ('ige', b, a)),
424 (('ult', a, ('umin', b, a)), False),
425 (('ult', ('umax', a, b), a), False),
426 (('uge', a, ('umax', b, a)), ('uge', a, b)),
427 (('uge', ('umin', a, b), a), ('uge', b, a)),
428
429 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
430 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
431 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
432 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
433 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
434 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
435 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
436 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
437 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
438 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
439 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
440 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
441 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
442 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
443 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
444 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
445
446 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
447 # negative.
448 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
449 ('iabs', ('ishr', a, b))),
450 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
451
452 (('fabs', ('slt', a, b)), ('slt', a, b)),
453 (('fabs', ('sge', a, b)), ('sge', a, b)),
454 (('fabs', ('seq', a, b)), ('seq', a, b)),
455 (('fabs', ('sne', a, b)), ('sne', a, b)),
456 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
457 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
458 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
459 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
460 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
461 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
462 # Emulating booleans
463 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
464 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
465 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
466 (('iand', 'a@bool32', 1.0), ('b2f', a)),
467 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
468 (('ineg', ('b2i32', 'a@32')), a),
469 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
470 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
471 # Comparison with the same args. Note that these are not done for
472 # the float versions because NaN always returns false on float
473 # inequalities.
474 (('ilt', a, a), False),
475 (('ige', a, a), True),
476 (('ieq', a, a), True),
477 (('ine', a, a), False),
478 (('ult', a, a), False),
479 (('uge', a, a), True),
480 # Logical and bit operations
481 (('fand', a, 0.0), 0.0),
482 (('iand', a, a), a),
483 (('iand', a, ~0), a),
484 (('iand', a, 0), 0),
485 (('ior', a, a), a),
486 (('ior', a, 0), a),
487 (('ior', a, True), True),
488 (('fxor', a, a), 0.0),
489 (('ixor', a, a), 0),
490 (('ixor', a, 0), a),
491 (('inot', ('inot', a)), a),
492 (('ior', ('iand', a, b), b), b),
493 (('ior', ('ior', a, b), b), ('ior', a, b)),
494 (('iand', ('ior', a, b), b), b),
495 (('iand', ('iand', a, b), b), ('iand', a, b)),
496 # DeMorgan's Laws
497 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
498 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
499 # Shift optimizations
500 (('ishl', 0, a), 0),
501 (('ishl', a, 0), a),
502 (('ishr', 0, a), 0),
503 (('ishr', a, 0), a),
504 (('ushr', 0, a), 0),
505 (('ushr', a, 0), a),
506 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
507 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
508 # Exponential/logarithmic identities
509 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
510 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
511 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
512 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
513 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
514 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
515 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
516 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
517 (('~fpow', a, 1.0), a),
518 (('~fpow', a, 2.0), ('fmul', a, a)),
519 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
520 (('~fpow', 2.0, a), ('fexp2', a)),
521 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
522 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
523 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
524 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
525 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
526 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
527 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
528 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
529 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
530 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
531 # Division and reciprocal
532 (('~fdiv', 1.0, a), ('frcp', a)),
533 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
534 (('~frcp', ('frcp', a)), a),
535 (('~frcp', ('fsqrt', a)), ('frsq', a)),
536 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
537 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
538 # Boolean simplifications
539 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
540 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
541 (('ieq', a, True), a),
542 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
543 (('ine', a, False), a),
544 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
545 (('bcsel', a, True, False), a),
546 (('bcsel', a, False, True), ('inot', a)),
547 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
548 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
549 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
550 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
551 (('bcsel', True, b, c), b),
552 (('bcsel', False, b, c), c),
553 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
554 # The result of this should be hit by constant propagation and, in the
555 # next round of opt_algebraic, get picked up by one of the above two.
556 (('bcsel', '#a', b, c), ('bcsel', ('ine', 'a', 0), b, c)),
557
558 (('bcsel', a, b, b), b),
559 (('fcsel', a, b, b), b),
560
561 # D3D Boolean emulation
562 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
563 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
564 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
565 ('ineg', ('b2i', ('iand', a, b)))),
566 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
567 ('ineg', ('b2i', ('ior', a, b)))),
568 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
569 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
570 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
571 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
572 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
573
574 # SM5 32-bit shifts are defined to use the 5 least significant bits
575 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
576 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
577 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
578
579 # Conversions
580 (('i2b32', ('b2i', 'a@32')), a),
581 (('f2i', ('ftrunc', a)), ('f2i', a)),
582 (('f2u', ('ftrunc', a)), ('f2u', a)),
583 (('i2b', ('ineg', a)), ('i2b', a)),
584 (('i2b', ('iabs', a)), ('i2b', a)),
585 (('fabs', ('b2f', a)), ('b2f', a)),
586 (('iabs', ('b2i', a)), ('b2i', a)),
587 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
588
589 # Ironically, mark these as imprecise because removing the conversions may
590 # preserve more precision than doing the conversions (e.g.,
591 # uint(float(0x81818181u)) == 0x81818200).
592 (('~f2i32', ('i2f', 'a@32')), a),
593 (('~f2i32', ('u2f', 'a@32')), a),
594 (('~f2u32', ('i2f', 'a@32')), a),
595 (('~f2u32', ('u2f', 'a@32')), a),
596
597 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
598 # says:
599 #
600 # It is undefined to convert a negative floating-point value to an
601 # uint.
602 #
603 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
604 # some optimizations in the i965 backend to proceed.
605 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
606 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
607 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
608 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
609
610 # Packing and then unpacking does nothing
611 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
612 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
613 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
614 ('unpack_64_2x32_split_y', a)), a),
615
616 # Byte extraction
617 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
618 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
619 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
620 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
621 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
622 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
623 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
624 ]
625
626 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
627 # patterns like those below.
628 for op in ('ushr', 'ishr'):
629 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
630 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
631 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
632
633 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
634
635 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
636 # patterns like those below.
637 for op in ('extract_u8', 'extract_i8'):
638 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
639 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
640 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
641
642 optimizations.extend([
643 # Word extraction
644 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
645 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
646 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
647 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
648 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
649
650 # Subtracts
651 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
652 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
653 (('ussub_4x8', a, 0), a),
654 (('ussub_4x8', a, ~0), 0),
655 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
656 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
657 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
658 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
659 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
660 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
661 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
662 (('iabs', ('isub', 0, a)), ('iabs', a)),
663
664 # Propagate negation up multiplication chains
665 (('fmul', ('fneg', a), b), ('fneg', ('fmul', a, b))),
666 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
667
668 # Propagate constants up multiplication chains
669 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
670 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
671 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
672 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
673
674 # Reassociate constants in add/mul chains so they can be folded together.
675 # For now, we mostly only handle cases where the constants are separated by
676 # a single non-constant. We could do better eventually.
677 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
678 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
679 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
680 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
681 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
682
683 # By definition...
684 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
685 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
686 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
687
688 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
689 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
690 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
691
692 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
693
694 # Misc. lowering
695 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod16'),
696 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod32'),
697 (('fmod@64', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod64'),
698 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod32'),
699 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
700 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
701
702 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
703 ('bcsel', ('ilt', 31, 'bits'), 'insert',
704 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
705 'options->lower_bitfield_insert'),
706 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
707 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
708 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
709 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
710 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
711 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
712
713 # Alternative lowering that doesn't rely on bfi.
714 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
715 ('bcsel', ('ilt', 31, 'bits'),
716 'insert',
717 ('ior',
718 ('iand', 'base', ('inot', ('bfm', 'bits', 'offset'))),
719 ('iand', ('ishl', 'insert', 'offset'), ('bfm', 'bits', 'offset')))),
720 'options->lower_bitfield_insert_to_shifts'),
721
722 # bfm lowering -- note that the NIR opcode is undefined if either arg is 32.
723 (('bfm', 'bits', 'offset'),
724 ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'),
725 'options->lower_bfm'),
726
727 (('ibitfield_extract', 'value', 'offset', 'bits'),
728 ('bcsel', ('ilt', 31, 'bits'), 'value',
729 ('ibfe', 'value', 'offset', 'bits')),
730 'options->lower_bitfield_extract'),
731
732 (('ubitfield_extract', 'value', 'offset', 'bits'),
733 ('bcsel', ('ult', 31, 'bits'), 'value',
734 ('ubfe', 'value', 'offset', 'bits')),
735 'options->lower_bitfield_extract'),
736
737 (('ibitfield_extract', 'value', 'offset', 'bits'),
738 ('bcsel', ('ieq', 0, 'bits'),
739 0,
740 ('ishr',
741 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
742 ('isub', 32, 'bits'))),
743 'options->lower_bitfield_extract_to_shifts'),
744
745 (('ubitfield_extract', 'value', 'offset', 'bits'),
746 ('iand',
747 ('ushr', 'value', 'offset'),
748 ('bcsel', ('ieq', 'bits', 32),
749 0xffffffff,
750 ('bfm', 'bits', 0))),
751 'options->lower_bitfield_extract_to_shifts'),
752
753 (('ifind_msb', 'value'),
754 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
755 'options->lower_ifind_msb'),
756
757 (('find_lsb', 'value'),
758 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
759 'options->lower_find_lsb'),
760
761 (('extract_i8', a, 'b@32'),
762 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
763 'options->lower_extract_byte'),
764
765 (('extract_u8', a, 'b@32'),
766 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
767 'options->lower_extract_byte'),
768
769 (('extract_i16', a, 'b@32'),
770 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
771 'options->lower_extract_word'),
772
773 (('extract_u16', a, 'b@32'),
774 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
775 'options->lower_extract_word'),
776
777 (('pack_unorm_2x16', 'v'),
778 ('pack_uvec2_to_uint',
779 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
780 'options->lower_pack_unorm_2x16'),
781
782 (('pack_unorm_4x8', 'v'),
783 ('pack_uvec4_to_uint',
784 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
785 'options->lower_pack_unorm_4x8'),
786
787 (('pack_snorm_2x16', 'v'),
788 ('pack_uvec2_to_uint',
789 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
790 'options->lower_pack_snorm_2x16'),
791
792 (('pack_snorm_4x8', 'v'),
793 ('pack_uvec4_to_uint',
794 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
795 'options->lower_pack_snorm_4x8'),
796
797 (('unpack_unorm_2x16', 'v'),
798 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
799 ('extract_u16', 'v', 1))),
800 65535.0),
801 'options->lower_unpack_unorm_2x16'),
802
803 (('unpack_unorm_4x8', 'v'),
804 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
805 ('extract_u8', 'v', 1),
806 ('extract_u8', 'v', 2),
807 ('extract_u8', 'v', 3))),
808 255.0),
809 'options->lower_unpack_unorm_4x8'),
810
811 (('unpack_snorm_2x16', 'v'),
812 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
813 ('extract_i16', 'v', 1))),
814 32767.0))),
815 'options->lower_unpack_snorm_2x16'),
816
817 (('unpack_snorm_4x8', 'v'),
818 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
819 ('extract_i8', 'v', 1),
820 ('extract_i8', 'v', 2),
821 ('extract_i8', 'v', 3))),
822 127.0))),
823 'options->lower_unpack_snorm_4x8'),
824
825 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
826 ])
827
828 # bit_size dependent lowerings
829 for bit_size in [8, 16, 32, 64]:
830 # convenience constants
831 intmax = (1 << (bit_size - 1)) - 1
832 intmin = 1 << (bit_size - 1)
833
834 optimizations += [
835 (('iadd_sat@' + str(bit_size), a, b),
836 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
837 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
838 (('isub_sat@' + str(bit_size), a, b),
839 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
840 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
841 ]
842
843 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
844
845 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
846 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
847 ('iand', (invert[left], a, b), (invert[right], c, d))))
848 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
849 ('ior', (invert[left], a, b), (invert[right], c, d))))
850
851 # Optimize x2bN(b2x(x)) -> x
852 for size in type_sizes('bool'):
853 aN = 'a@' + str(size)
854 f2bN = 'f2b' + str(size)
855 i2bN = 'i2b' + str(size)
856 optimizations.append(((f2bN, ('b2f', aN)), a))
857 optimizations.append(((i2bN, ('b2i', aN)), a))
858
859 # Optimize x2yN(b2x(x)) -> b2y
860 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
861 if x != 'f' and y != 'f' and x != y:
862 continue
863
864 b2x = 'b2f' if x == 'f' else 'b2i'
865 b2y = 'b2f' if y == 'f' else 'b2i'
866 x2yN = '{}2{}'.format(x, y)
867 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
868
869 def fexp2i(exp, bits):
870 # We assume that exp is already in the right range.
871 if bits == 16:
872 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
873 elif bits == 32:
874 return ('ishl', ('iadd', exp, 127), 23)
875 elif bits == 64:
876 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
877 else:
878 assert False
879
880 def ldexp(f, exp, bits):
881 # First, we clamp exp to a reasonable range. The maximum possible range
882 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
883 # a maximum range of [-149, 127]. This means that we can potentially have
884 # a swing of +-276. If you start with FLT_MAX, you actually have to do
885 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
886 # spec, on the other hand, only requires that we handle an exponent value
887 # in the range [-126, 128]. This implementation is *mostly* correct; it
888 # handles a range on exp of [-252, 254] which allows you to create any
889 # value (including denorms if the hardware supports it) and to adjust the
890 # exponent of any normal value to anything you want.
891 if bits == 16:
892 exp = ('imin', ('imax', exp, -28), 30)
893 elif bits == 32:
894 exp = ('imin', ('imax', exp, -252), 254)
895 elif bits == 64:
896 exp = ('imin', ('imax', exp, -2044), 2046)
897 else:
898 assert False
899
900 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
901 # (We use ishr which isn't the same for -1, but the -1 case still works
902 # since we use exp-exp/2 as the second exponent.) While the spec
903 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
904 # work with denormals and doesn't allow for the full swing in exponents
905 # that you can get with normalized values. Instead, we create two powers
906 # of two and multiply by them each in turn. That way the effective range
907 # of our exponent is doubled.
908 pow2_1 = fexp2i(('ishr', exp, 1), bits)
909 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
910 return ('fmul', ('fmul', f, pow2_1), pow2_2)
911
912 optimizations += [
913 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
914 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
915 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
916 ]
917
918 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
919 def bitfield_reverse(u):
920 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
921 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
922 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
923 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
924 step5 = ('ior', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
925
926 return step5
927
928 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
929
930 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
931 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
932 # and, if a is a NaN then the second comparison will fail anyway.
933 for op in ['flt', 'fge', 'feq']:
934 optimizations += [
935 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
936 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
937 ]
938
939 # Add optimizations to handle the case where the result of a ternary is
940 # compared to a constant. This way we can take things like
941 #
942 # (a ? 0 : 1) > 0
943 #
944 # and turn it into
945 #
946 # a ? (0 > 0) : (1 > 0)
947 #
948 # which constant folding will eat for lunch. The resulting ternary will
949 # further get cleaned up by the boolean reductions above and we will be
950 # left with just the original variable "a".
951 for op in ['flt', 'fge', 'feq', 'fne',
952 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
953 optimizations += [
954 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
955 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
956 ((op, '#d', ('bcsel', a, '#b', '#c')),
957 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
958 ]
959
960
961 # For example, this converts things like
962 #
963 # 1 + mix(0, a - 1, condition)
964 #
965 # into
966 #
967 # mix(1, (a-1)+1, condition)
968 #
969 # Other optimizations will rearrange the constants.
970 for op in ['fadd', 'fmul', 'iadd', 'imul']:
971 optimizations += [
972 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
973 ]
974
975 # This section contains "late" optimizations that should be run before
976 # creating ffmas and calling regular optimizations for the final time.
977 # Optimizations should go here if they help code generation and conflict
978 # with the regular optimizations.
979 before_ffma_optimizations = [
980 # Propagate constants down multiplication chains
981 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
982 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
983 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
984 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
985
986 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
987 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
988 (('~fadd', ('fneg', a), a), 0.0),
989 (('iadd', ('ineg', a), a), 0),
990 (('iadd', ('ineg', a), ('iadd', a, b)), b),
991 (('iadd', a, ('iadd', ('ineg', a), b)), b),
992 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
993 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
994 ]
995
996 # This section contains "late" optimizations that should be run after the
997 # regular optimizations have finished. Optimizations should go here if
998 # they help code generation but do not necessarily produce code that is
999 # more easily optimizable.
1000 late_optimizations = [
1001 # Most of these optimizations aren't quite safe when you get infinity or
1002 # Nan involved but the first one should be fine.
1003 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1004 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1005 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1006 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1007 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1008 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1009
1010 (('~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)))),
1011
1012 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1013 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1014 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1015 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1016
1017 (('b2f(is_used_more_than_once)', ('inot', 'a@1')), ('bcsel', a, 0.0, 1.0)),
1018 (('fneg(is_used_more_than_once)', ('b2f', ('inot', 'a@1'))), ('bcsel', a, -0.0, -1.0)),
1019
1020 # we do these late so that we don't get in the way of creating ffmas
1021 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1022 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1023
1024 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1025 ]
1026
1027 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1028 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1029 before_ffma_optimizations).render())
1030 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1031 late_optimizations).render())