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