nir/algebraic: add optimization pattern for ('ult', a, ('and', b, a)) and friends.
[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 e = 'e'
39
40 # Written in the form (<search>, <replace>) where <search> is an expression
41 # and <replace> is either an expression or a value. An expression is
42 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
43 # where each source is either an expression or a value. A value can be
44 # either a numeric constant or a string representing a variable name.
45 #
46 # If the opcode in a search expression is prefixed by a '~' character, this
47 # indicates that the operation is inexact. Such operations will only get
48 # applied to SSA values that do not have the exact bit set. This should be
49 # used by by any optimizations that are not bit-for-bit exact. It should not,
50 # however, be used for backend-requested lowering operations as those need to
51 # happen regardless of precision.
52 #
53 # Variable names are specified as "[#]name[@type][(cond)]" where "#" inicates
54 # that the given variable will only match constants and the type indicates that
55 # the given variable will only match values from ALU instructions with the
56 # given output type, and (cond) specifies an additional condition function
57 # (see nir_search_helpers.h).
58 #
59 # For constants, you have to be careful to make sure that it is the right
60 # type because python is unaware of the source and destination types of the
61 # opcodes.
62 #
63 # All expression types can have a bit-size specified. For opcodes, this
64 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
65 # type and size. In the search half of the expression this indicates that it
66 # should only match that particular bit-size. In the replace half of the
67 # expression this indicates that the constructed value should have that
68 # bit-size.
69
70 optimizations = [
71
72 (('imul', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b)), '!options->lower_bitshift'),
73 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitshift'),
74 (('ishl', a, '#b@32'), ('imul', a, ('ishl', 1, b)), 'options->lower_bitshift'),
75
76 (('unpack_64_2x32_split_x', ('imul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
77 (('unpack_64_2x32_split_x', ('umul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
78 (('imul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('imul_high', a, b)), 'options->lower_mul_2x32_64'),
79 (('umul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('umul_high', a, b)), 'options->lower_mul_2x32_64'),
80 (('udiv', a, 1), a),
81 (('idiv', a, 1), a),
82 (('umod', a, 1), 0),
83 (('imod', a, 1), 0),
84 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b)), '!options->lower_bitshift'),
85 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
86 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
87 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
88
89 (('fneg', ('fneg', a)), a),
90 (('ineg', ('ineg', a)), a),
91 (('fabs', ('fabs', a)), ('fabs', a)),
92 (('fabs', ('fneg', a)), ('fabs', a)),
93 (('fabs', ('u2f', a)), ('u2f', a)),
94 (('iabs', ('iabs', a)), ('iabs', a)),
95 (('iabs', ('ineg', a)), ('iabs', a)),
96 (('f2b', ('fneg', a)), ('f2b', a)),
97 (('i2b', ('ineg', a)), ('i2b', a)),
98 (('~fadd', a, 0.0), a),
99 (('iadd', a, 0), a),
100 (('usadd_4x8', a, 0), a),
101 (('usadd_4x8', a, ~0), ~0),
102 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
103 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
104 (('~fadd', ('fneg', a), a), 0.0),
105 (('iadd', ('ineg', a), a), 0),
106 (('iadd', ('ineg', a), ('iadd', a, b)), b),
107 (('iadd', a, ('iadd', ('ineg', a), b)), b),
108 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
109 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
110 (('fadd', ('fsat', a), ('fsat', ('fneg', a))), ('fsat', ('fabs', a))),
111 (('~fmul', a, 0.0), 0.0),
112 (('imul', a, 0), 0),
113 (('umul_unorm_4x8', a, 0), 0),
114 (('umul_unorm_4x8', a, ~0), a),
115 (('fmul', a, 1.0), a),
116 (('imul', a, 1), a),
117 (('fmul', a, -1.0), ('fneg', a)),
118 (('imul', a, -1), ('ineg', a)),
119 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
120 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
121 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
122 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
123 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
124 (('~ffma', 0.0, a, b), b),
125 (('~ffma', a, b, 0.0), ('fmul', a, b)),
126 (('ffma', 1.0, a, b), ('fadd', a, b)),
127 (('ffma', -1.0, a, b), ('fadd', ('fneg', a), b)),
128 (('~flrp', a, b, 0.0), a),
129 (('~flrp', a, b, 1.0), b),
130 (('~flrp', a, a, b), a),
131 (('~flrp', 0.0, a, b), ('fmul', a, b)),
132
133 # flrp(a, a + b, c) => a + flrp(0, b, c) => a + (b * c)
134 (('~flrp', a, ('fadd(is_used_once)', a, b), c), ('fadd', ('fmul', b, c), a)),
135 (('~flrp@32', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp32'),
136 (('~flrp@64', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp64'),
137
138 (('~flrp@32', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp32'),
139 (('~flrp@64', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp64'),
140
141 (('~flrp@32', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp32'),
142 (('~flrp@64', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp64'),
143
144 (('~flrp', ('fmul(is_used_once)', a, b), ('fmul(is_used_once)', a, c), d), ('fmul', ('flrp', b, c, d), a)),
145
146 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
147 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
148 (('ftrunc', a), ('bcsel', ('flt', a, 0.0), ('fneg', ('ffloor', ('fabs', a))), ('ffloor', ('fabs', a))), 'options->lower_ftrunc'),
149 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
150 (('fadd', a, ('fneg', ('ffract', a))), ('ffloor', a), '!options->lower_ffloor'),
151 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
152 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
153 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
154 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
155 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
156 # These are the same as the previous three rules, but it depends on
157 # 1-fsat(x) <=> fsat(1-x). See below.
158 (('~fadd@32', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp32'),
159 (('~fadd@64', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp64'),
160
161 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
162 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
163 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
164 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
165 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
166
167 (('~fmul', ('fadd', ('iand', ('ineg', ('b2i32', 'a@bool')), ('fmul', b, c)), '#d'), '#e'),
168 ('bcsel', a, ('fmul', ('fadd', ('fmul', b, c), d), e), ('fmul', d, e))),
169
170 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d)),
171 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
172 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
173 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
174
175 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
176 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
177
178 # If x >= 0 and x <= 1: fsat(1 - x) == 1 - fsat(x) trivially
179 # If x < 0: 1 - fsat(x) => 1 - 0 => 1 and fsat(1 - x) => fsat(> 1) => 1
180 # If x > 1: 1 - fsat(x) => 1 - 1 => 0 and fsat(1 - x) => fsat(< 0) => 0
181 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
182
183 # (a * #b + #c) << #d
184 # ((a * #b) << #d) + (#c << #d)
185 # (a * (#b << #d)) + (#c << #d)
186 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
187 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
188
189 # (a * #b) << #c
190 # a * (#b << #c)
191 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
192
193 # Comparison simplifications
194 (('~inot', ('flt', a, b)), ('fge', a, b)),
195 (('~inot', ('fge', a, b)), ('flt', a, b)),
196 (('~inot', ('feq', a, b)), ('fne', a, b)),
197 (('~inot', ('fne', a, b)), ('feq', a, b)),
198 (('inot', ('ilt', a, b)), ('ige', a, b)),
199 (('inot', ('ult', a, b)), ('uge', a, b)),
200 (('inot', ('ige', a, b)), ('ilt', a, b)),
201 (('inot', ('uge', a, b)), ('ult', a, b)),
202 (('inot', ('ieq', a, b)), ('ine', a, b)),
203 (('inot', ('ine', a, b)), ('ieq', a, b)),
204
205 # This helps some shaders because, after some optimizations, they end up
206 # with patterns like (-a < -b) || (b < a). In an ideal world, this sort of
207 # matching would be handled by CSE.
208 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
209 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
210 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
211 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
212 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
213 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
214 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
215 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
216 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
217 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
218
219 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
220 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
221 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
222 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
223 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
224 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
225
226 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
227 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
228 (('fge', 0.0, ('fsat(is_used_once)', a)), ('fge', 0.0, a)),
229 (('flt', 0.0, ('fsat(is_used_once)', a)), ('flt', 0.0, a)),
230
231 # 0.0 >= b2f(a)
232 # b2f(a) <= 0.0
233 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
234 # inot(a)
235 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
236
237 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
238
239 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
240 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
241 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
242 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
243 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
244 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
245 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
246 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
247 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
248 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
249 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
250 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
251 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
252 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
253 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
254 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
255 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
256 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
257 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
258 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
259
260 # -(b2f(a) + b2f(b)) < 0
261 # 0 < b2f(a) + b2f(b)
262 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
263 # a || b
264 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
265 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
266
267 # -(b2f(a) + b2f(b)) >= 0
268 # 0 >= b2f(a) + b2f(b)
269 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
270 # !(a || b)
271 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
272 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
273
274 (('flt', a, ('fneg', a)), ('flt', a, 0.0)),
275 (('fge', a, ('fneg', a)), ('fge', a, 0.0)),
276
277 # Some optimizations (below) convert things like (a < b || c < b) into
278 # (min(a, c) < b). However, this interfers with the previous optimizations
279 # that try to remove comparisons with negated sums of b2f. This just
280 # breaks that apart.
281 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
282 ('ior', ('flt', c, 0.0), ('ior', a, b))),
283
284 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
285 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
286 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
287 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
288
289 # Cannot remove the addition from ilt or ige due to overflow.
290 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
291 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
292
293 # fmin(-b2f(a), b) >= 0.0
294 # -b2f(a) >= 0.0 && b >= 0.0
295 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
296 # b2f(a) == 0.0 && b >= 0.0
297 # a == False && b >= 0.0
298 # !a && b >= 0.0
299 #
300 # The fge in the second replacement is not a typo. I leave the proof that
301 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
302 # reader.
303 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
304 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
305
306 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
307 (('fne', ('b2f', 'a@1'), 0.0), a),
308 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
309 (('ine', ('b2i', 'a@1'), 0), a),
310
311 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
312 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
313 (('fge', ('u2f', a), 0.0), True),
314 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
315 (('flt', ('u2f', a), 0.0), False),
316 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
317 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
318 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
319 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
320 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
321 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
322 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
323
324 # 0.0 < fabs(a)
325 # fabs(a) > 0.0
326 # fabs(a) != 0.0 because fabs(a) must be >= 0
327 # a != 0.0
328 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
329
330 # -fabs(a) < 0.0
331 # fabs(a) > 0.0
332 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
333
334 # 0.0 >= fabs(a)
335 # 0.0 == fabs(a) because fabs(a) must be >= 0
336 # 0.0 == a
337 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
338
339 # -fabs(a) >= 0.0
340 # 0.0 >= fabs(a)
341 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
342
343 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
344 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
345 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
346 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
347
348 # fmin(b2f(a), b)
349 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
350 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
351 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
352 #
353 # Since b is a constant, constant folding will eliminate the fmin and the
354 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
355 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
356
357 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
358
359 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
360 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
361 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
362 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
363 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
364 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
365 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
366 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
367 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
368 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
369 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
370 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
371 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
372 (('bcsel', a, True, b), ('ior', a, b)),
373 (('bcsel', a, a, b), ('ior', a, b)),
374 (('bcsel', a, b, False), ('iand', a, b)),
375 (('bcsel', a, b, a), ('iand', a, b)),
376 (('fmin', a, a), a),
377 (('fmax', a, a), a),
378 (('imin', a, a), a),
379 (('imax', a, a), a),
380 (('umin', a, a), a),
381 (('umax', a, a), a),
382 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
383 (('umax', ('umax', a, b), b), ('umax', a, b)),
384 (('imax', ('imax', a, b), b), ('imax', a, b)),
385 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
386 (('umin', ('umin', a, b), b), ('umin', a, b)),
387 (('imin', ('imin', a, b), b), ('imin', a, b)),
388 (('fmax', a, ('fneg', a)), ('fabs', a)),
389 (('imax', a, ('ineg', a)), ('iabs', a)),
390 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
391 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
392 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
393 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
394 (('fmin', a, ('fabs', a)), a),
395 (('imin', a, ('iabs', a)), a),
396 (('fmax', a, ('fneg', ('fabs', a))), a),
397 (('imax', a, ('ineg', ('iabs', a))), a),
398 (('fmax', a, ('fabs', a)), ('fabs', a)),
399 (('imax', a, ('iabs', a)), ('iabs', a)),
400 (('fmax', a, ('fneg', a)), ('fabs', a)),
401 (('imax', a, ('ineg', a)), ('iabs', a)),
402 (('~fmax', ('fabs', a), 0.0), ('fabs', a)),
403 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
404 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
405 (('~fmin', ('fmax', a, -1.0), 0.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
406 (('~fmax', ('fmin', a, 0.0), -1.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
407 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
408 (('fsat', ('b2f', a)), ('b2f', a)),
409 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
410 (('fsat', ('fsat', a)), ('fsat', a)),
411 (('fsat', ('fneg(is_used_once)', ('fadd(is_used_once)', a, b))), ('fsat', ('fadd', ('fneg', a), ('fneg', b))), '!options->lower_negate && !options->lower_fsat'),
412 (('fsat', ('fneg(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fneg', a), b)), '!options->lower_negate && !options->lower_fsat'),
413 (('fsat', ('fabs(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fabs', a), ('fabs', b))), '!options->lower_fsat'),
414 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
415 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
416 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
417 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
418 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
419 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
420 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
421 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
422 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
423 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
424 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
425 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
426 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
427 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
428 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
429 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
430 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
431 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
432 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
433 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
434 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
435 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
436
437 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
438 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
439 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
440 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
441 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
442 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
443 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
444 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
445 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
446 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
447 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
448 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
449 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
450 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
451 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
452 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
453
454 # Common pattern like 'if (i == 0 || i == 1 || ...)'
455 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
456 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
457 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
458
459 # The (i2f32, ...) part is an open-coded fsign. When that is combined with
460 # the bcsel, it's basically copysign(1.0, a). There is no copysign in NIR,
461 # so emit an open-coded version of that.
462 (('bcsel@32', ('feq', a, 0.0), 1.0, ('i2f32', ('iadd', ('b2i32', ('flt', 0.0, 'a@32')), ('ineg', ('b2i32', ('flt', 'a@32', 0.0)))))),
463 ('ior', 0x3f800000, ('iand', a, 0x80000000))),
464
465 (('ior', a, ('ieq', a, False)), True),
466 (('ior', a, ('inot', a)), -1),
467
468 (('ine', ('ineg', ('b2i32', 'a@1')), ('ineg', ('b2i32', 'b@1'))), ('ine', a, b)),
469 (('b2i32', ('ine', 'a@1', 'b@1')), ('b2i32', ('ixor', a, b))),
470
471 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
472
473 # These patterns can result when (a < b || a < c) => (a < min(b, c))
474 # transformations occur before constant propagation and loop-unrolling.
475 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
476 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
477 (('~fge', a, ('fmin', b, a)), True),
478 (('~fge', ('fmax', a, b), a), True),
479 (('~flt', a, ('fmin', b, a)), False),
480 (('~flt', ('fmax', a, b), a), False),
481 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
482 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
483
484 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
485 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
486 (('ige', a, ('imin', b, a)), True),
487 (('ige', ('imax', a, b), a), True),
488 (('ult', a, ('umax', b, a)), ('ult', a, b)),
489 (('ult', ('umin', a, b), a), ('ult', b, a)),
490 (('uge', a, ('umin', b, a)), True),
491 (('uge', ('umax', a, b), a), True),
492 (('ilt', a, ('imin', b, a)), False),
493 (('ilt', ('imax', a, b), a), False),
494 (('ige', a, ('imax', b, a)), ('ige', a, b)),
495 (('ige', ('imin', a, b), a), ('ige', b, a)),
496 (('ult', a, ('umin', b, a)), False),
497 (('ult', ('umax', a, b), a), False),
498 (('uge', a, ('umax', b, a)), ('uge', a, b)),
499 (('uge', ('umin', a, b), a), ('uge', b, a)),
500 (('ult', a, ('iand', b, a)), False),
501 (('ult', ('ior', a, b), a), False),
502 (('uge', a, ('iand', b, a)), True),
503 (('uge', ('ior', a, b), a), True),
504
505 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
506 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
507 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
508 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
509 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
510 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
511 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
512 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
513 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
514 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
515 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
516 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
517 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
518 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
519 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
520 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
521
522 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
523 # negative.
524 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
525 ('iabs', ('ishr', a, b))),
526 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
527
528 (('fabs', ('slt', a, b)), ('slt', a, b)),
529 (('fabs', ('sge', a, b)), ('sge', a, b)),
530 (('fabs', ('seq', a, b)), ('seq', a, b)),
531 (('fabs', ('sne', a, b)), ('sne', a, b)),
532 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
533 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
534 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
535 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
536 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
537 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
538 # Emulating booleans
539 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
540 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
541 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
542 (('iand', 'a@bool32', 1.0), ('b2f', a)),
543 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
544 (('ineg', ('b2i32', 'a@32')), a),
545 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
546 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
547 # Comparison with the same args. Note that these are not done for
548 # the float versions because NaN always returns false on float
549 # inequalities.
550 (('ilt', a, a), False),
551 (('ige', a, a), True),
552 (('ieq', a, a), True),
553 (('ine', a, a), False),
554 (('ult', a, a), False),
555 (('uge', a, a), True),
556 # Logical and bit operations
557 (('fand', a, 0.0), 0.0),
558 (('iand', a, a), a),
559 (('iand', a, ~0), a),
560 (('iand', a, 0), 0),
561 (('ior', a, a), a),
562 (('ior', a, 0), a),
563 (('ior', a, True), True),
564 (('fxor', a, a), 0.0),
565 (('ixor', a, a), 0),
566 (('ixor', a, 0), a),
567 (('inot', ('inot', a)), a),
568 (('ior', ('iand', a, b), b), b),
569 (('ior', ('ior', a, b), b), ('ior', a, b)),
570 (('iand', ('ior', a, b), b), b),
571 (('iand', ('iand', a, b), b), ('iand', a, b)),
572 # DeMorgan's Laws
573 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
574 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
575 # Shift optimizations
576 (('ishl', 0, a), 0),
577 (('ishl', a, 0), a),
578 (('ishr', 0, a), 0),
579 (('ishr', a, 0), a),
580 (('ushr', 0, a), 0),
581 (('ushr', a, 0), a),
582 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
583 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
584 # Exponential/logarithmic identities
585 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
586 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
587 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
588 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
589 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
590 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
591 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
592 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
593 (('~fpow', a, 1.0), a),
594 (('~fpow', a, 2.0), ('fmul', a, a)),
595 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
596 (('~fpow', 2.0, a), ('fexp2', a)),
597 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
598 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
599 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
600 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
601 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
602 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
603 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
604 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
605 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
606 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
607 (('bcsel', ('flt', a, 0.0), 0.0, ('fsqrt', a)), ('fsqrt', ('fmax', a, 0.0))),
608 # Division and reciprocal
609 (('~fdiv', 1.0, a), ('frcp', a)),
610 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
611 (('~frcp', ('frcp', a)), a),
612 (('~frcp', ('fsqrt', a)), ('frsq', a)),
613 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
614 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
615 # Boolean simplifications
616 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
617 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
618 (('ieq', a, True), a),
619 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
620 (('ine', a, False), a),
621 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
622 (('bcsel', a, True, False), a),
623 (('bcsel', a, False, True), ('inot', a)),
624 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
625 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
626 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
627 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
628 (('bcsel', True, b, c), b),
629 (('bcsel', False, b, c), c),
630 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
631
632 (('bcsel', a, b, b), b),
633 (('fcsel', a, b, b), b),
634
635 # D3D Boolean emulation
636 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
637 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
638 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
639 ('ineg', ('b2i', ('iand', a, b)))),
640 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
641 ('ineg', ('b2i', ('ior', a, b)))),
642 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
643 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
644 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
645 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
646 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
647
648 # SM5 32-bit shifts are defined to use the 5 least significant bits
649 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
650 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
651 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
652
653 # Conversions
654 (('i2b32', ('b2i', 'a@32')), a),
655 (('f2i', ('ftrunc', a)), ('f2i', a)),
656 (('f2u', ('ftrunc', a)), ('f2u', a)),
657 (('i2b', ('ineg', a)), ('i2b', a)),
658 (('i2b', ('iabs', a)), ('i2b', a)),
659 (('fabs', ('b2f', a)), ('b2f', a)),
660 (('iabs', ('b2i', a)), ('b2i', a)),
661 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
662
663 # Ironically, mark these as imprecise because removing the conversions may
664 # preserve more precision than doing the conversions (e.g.,
665 # uint(float(0x81818181u)) == 0x81818200).
666 (('~f2i32', ('i2f', 'a@32')), a),
667 (('~f2i32', ('u2f', 'a@32')), a),
668 (('~f2u32', ('i2f', 'a@32')), a),
669 (('~f2u32', ('u2f', 'a@32')), a),
670
671 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
672 # says:
673 #
674 # It is undefined to convert a negative floating-point value to an
675 # uint.
676 #
677 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
678 # some optimizations in the i965 backend to proceed.
679 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
680 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
681 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
682 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
683
684 (('~fmin', ('fabs', a), 1.0), ('fsat', ('fabs', a)), '!options->lower_fsat'),
685
686 # The result of the multiply must be in [-1, 0], so the result of the ffma
687 # must be in [0, 1].
688 (('flt', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), False),
689 (('flt', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), False),
690 (('fmax', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0)),
691 (('fmax', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0)),
692
693 # Packing and then unpacking does nothing
694 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
695 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
696 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
697 ('unpack_64_2x32_split_y', a)), a),
698
699 # Byte extraction
700 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
701 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
702 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
703 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
704 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
705 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
706 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
707 ]
708
709 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
710 # patterns like those below.
711 for op in ('ushr', 'ishr'):
712 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
713 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
714 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
715
716 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
717
718 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
719 # patterns like those below.
720 for op in ('extract_u8', 'extract_i8'):
721 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
722 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
723 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
724
725 optimizations.extend([
726 # Word extraction
727 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
728 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
729 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
730 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
731 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
732
733 # Subtracts
734 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
735 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
736 (('ussub_4x8', a, 0), a),
737 (('ussub_4x8', a, ~0), 0),
738 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
739 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
740 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
741 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
742 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
743 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
744 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
745 (('iabs', ('isub', 0, a)), ('iabs', a)),
746
747 # Propagate negation up multiplication chains
748 (('fmul(is_used_by_non_fsat)', ('fneg', a), b), ('fneg', ('fmul', a, b))),
749 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
750
751 # Propagate constants up multiplication chains
752 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
753 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
754 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
755 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
756
757 # Reassociate constants in add/mul chains so they can be folded together.
758 # For now, we mostly only handle cases where the constants are separated by
759 # a single non-constant. We could do better eventually.
760 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
761 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
762 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
763 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
764 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
765
766 # By definition...
767 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
768 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
769 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
770
771 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
772 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
773 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
774
775 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
776
777 # Misc. lowering
778 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
779 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
780 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
781 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
782 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
783
784 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
785 ('bcsel', ('ilt', 31, 'bits'), 'insert',
786 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
787 'options->lower_bitfield_insert'),
788 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
789 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
790 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
791 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
792 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
793 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
794
795 # Alternative lowering that doesn't rely on bfi.
796 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
797 ('bcsel', ('ilt', 31, 'bits'),
798 'insert',
799 ('ior',
800 ('iand', 'base', ('inot', ('bfm', 'bits', 'offset'))),
801 ('iand', ('ishl', 'insert', 'offset'), ('bfm', 'bits', 'offset')))),
802 'options->lower_bitfield_insert_to_shifts'),
803
804 # bfm lowering -- note that the NIR opcode is undefined if either arg is 32.
805 (('bfm', 'bits', 'offset'),
806 ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'),
807 'options->lower_bfm'),
808
809 (('ibitfield_extract', 'value', 'offset', 'bits'),
810 ('bcsel', ('ilt', 31, 'bits'), 'value',
811 ('ibfe', 'value', 'offset', 'bits')),
812 'options->lower_bitfield_extract'),
813
814 (('ubitfield_extract', 'value', 'offset', 'bits'),
815 ('bcsel', ('ult', 31, 'bits'), 'value',
816 ('ubfe', 'value', 'offset', 'bits')),
817 'options->lower_bitfield_extract'),
818
819 (('ibitfield_extract', 'value', 'offset', 'bits'),
820 ('bcsel', ('ieq', 0, 'bits'),
821 0,
822 ('ishr',
823 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
824 ('isub', 32, 'bits'))),
825 'options->lower_bitfield_extract_to_shifts'),
826
827 (('ubitfield_extract', 'value', 'offset', 'bits'),
828 ('iand',
829 ('ushr', 'value', 'offset'),
830 ('bcsel', ('ieq', 'bits', 32),
831 0xffffffff,
832 ('bfm', 'bits', 0))),
833 'options->lower_bitfield_extract_to_shifts'),
834
835 (('ifind_msb', 'value'),
836 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
837 'options->lower_ifind_msb'),
838
839 (('find_lsb', 'value'),
840 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
841 'options->lower_find_lsb'),
842
843 (('extract_i8', a, 'b@32'),
844 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
845 'options->lower_extract_byte'),
846
847 (('extract_u8', a, 'b@32'),
848 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
849 'options->lower_extract_byte'),
850
851 (('extract_i16', a, 'b@32'),
852 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
853 'options->lower_extract_word'),
854
855 (('extract_u16', a, 'b@32'),
856 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
857 'options->lower_extract_word'),
858
859 (('pack_unorm_2x16', 'v'),
860 ('pack_uvec2_to_uint',
861 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
862 'options->lower_pack_unorm_2x16'),
863
864 (('pack_unorm_4x8', 'v'),
865 ('pack_uvec4_to_uint',
866 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
867 'options->lower_pack_unorm_4x8'),
868
869 (('pack_snorm_2x16', 'v'),
870 ('pack_uvec2_to_uint',
871 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
872 'options->lower_pack_snorm_2x16'),
873
874 (('pack_snorm_4x8', 'v'),
875 ('pack_uvec4_to_uint',
876 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
877 'options->lower_pack_snorm_4x8'),
878
879 (('unpack_unorm_2x16', 'v'),
880 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
881 ('extract_u16', 'v', 1))),
882 65535.0),
883 'options->lower_unpack_unorm_2x16'),
884
885 (('unpack_unorm_4x8', 'v'),
886 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
887 ('extract_u8', 'v', 1),
888 ('extract_u8', 'v', 2),
889 ('extract_u8', 'v', 3))),
890 255.0),
891 'options->lower_unpack_unorm_4x8'),
892
893 (('unpack_snorm_2x16', 'v'),
894 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
895 ('extract_i16', 'v', 1))),
896 32767.0))),
897 'options->lower_unpack_snorm_2x16'),
898
899 (('unpack_snorm_4x8', 'v'),
900 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
901 ('extract_i8', 'v', 1),
902 ('extract_i8', 'v', 2),
903 ('extract_i8', 'v', 3))),
904 127.0))),
905 'options->lower_unpack_snorm_4x8'),
906
907 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
908 (('fsign', a), ('fsub', ('b2f', ('flt', 0.0, a)), ('b2f', ('flt', a, 0.0))), 'options->lower_fsign'),
909 ])
910
911 # bit_size dependent lowerings
912 for bit_size in [8, 16, 32, 64]:
913 # convenience constants
914 intmax = (1 << (bit_size - 1)) - 1
915 intmin = 1 << (bit_size - 1)
916
917 optimizations += [
918 (('iadd_sat@' + str(bit_size), a, b),
919 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
920 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
921 (('isub_sat@' + str(bit_size), a, b),
922 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
923 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
924 ]
925
926 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
927
928 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
929 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
930 ('iand', (invert[left], a, b), (invert[right], c, d))))
931 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
932 ('ior', (invert[left], a, b), (invert[right], c, d))))
933
934 # Optimize x2bN(b2x(x)) -> x
935 for size in type_sizes('bool'):
936 aN = 'a@' + str(size)
937 f2bN = 'f2b' + str(size)
938 i2bN = 'i2b' + str(size)
939 optimizations.append(((f2bN, ('b2f', aN)), a))
940 optimizations.append(((i2bN, ('b2i', aN)), a))
941
942 # Optimize x2yN(b2x(x)) -> b2y
943 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
944 if x != 'f' and y != 'f' and x != y:
945 continue
946
947 b2x = 'b2f' if x == 'f' else 'b2i'
948 b2y = 'b2f' if y == 'f' else 'b2i'
949 x2yN = '{}2{}'.format(x, y)
950 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
951
952 # Optimize away x2xN(a@N)
953 for t in ['int', 'uint', 'float']:
954 for N in type_sizes(t):
955 x2xN = '{0}2{0}{1}'.format(t[0], N)
956 aN = 'a@{0}'.format(N)
957 optimizations.append(((x2xN, aN), a))
958
959 # Optimize x2xN(y2yM(a@P)) -> y2yN(a) for integers
960 # In particular, we can optimize away everything except upcast of downcast and
961 # upcasts where the type differs from the other cast
962 for N, M in itertools.product(type_sizes('uint'), type_sizes('uint')):
963 if N < M:
964 # The outer cast is a down-cast. It doesn't matter what the size of the
965 # argument of the inner cast is because we'll never been in the upcast
966 # of downcast case. Regardless of types, we'll always end up with y2yN
967 # in the end.
968 for x, y in itertools.product(['i', 'u'], ['i', 'u']):
969 x2xN = '{0}2{0}{1}'.format(x, N)
970 y2yM = '{0}2{0}{1}'.format(y, M)
971 y2yN = '{0}2{0}{1}'.format(y, N)
972 optimizations.append(((x2xN, (y2yM, a)), (y2yN, a)))
973 elif N > M:
974 # If the outer cast is an up-cast, we have to be more careful about the
975 # size of the argument of the inner cast and with types. In this case,
976 # the type is always the type of type up-cast which is given by the
977 # outer cast.
978 for P in type_sizes('uint'):
979 # We can't optimize away up-cast of down-cast.
980 if M < P:
981 continue
982
983 # Because we're doing down-cast of down-cast, the types always have
984 # to match between the two casts
985 for x in ['i', 'u']:
986 x2xN = '{0}2{0}{1}'.format(x, N)
987 x2xM = '{0}2{0}{1}'.format(x, M)
988 aP = 'a@{0}'.format(P)
989 optimizations.append(((x2xN, (x2xM, aP)), (x2xN, a)))
990 else:
991 # The N == M case is handled by other optimizations
992 pass
993
994 def fexp2i(exp, bits):
995 # We assume that exp is already in the right range.
996 if bits == 16:
997 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
998 elif bits == 32:
999 return ('ishl', ('iadd', exp, 127), 23)
1000 elif bits == 64:
1001 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
1002 else:
1003 assert False
1004
1005 def ldexp(f, exp, bits):
1006 # First, we clamp exp to a reasonable range. The maximum possible range
1007 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
1008 # a maximum range of [-149, 127]. This means that we can potentially have
1009 # a swing of +-276. If you start with FLT_MAX, you actually have to do
1010 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
1011 # spec, on the other hand, only requires that we handle an exponent value
1012 # in the range [-126, 128]. This implementation is *mostly* correct; it
1013 # handles a range on exp of [-252, 254] which allows you to create any
1014 # value (including denorms if the hardware supports it) and to adjust the
1015 # exponent of any normal value to anything you want.
1016 if bits == 16:
1017 exp = ('imin', ('imax', exp, -28), 30)
1018 elif bits == 32:
1019 exp = ('imin', ('imax', exp, -252), 254)
1020 elif bits == 64:
1021 exp = ('imin', ('imax', exp, -2044), 2046)
1022 else:
1023 assert False
1024
1025 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
1026 # (We use ishr which isn't the same for -1, but the -1 case still works
1027 # since we use exp-exp/2 as the second exponent.) While the spec
1028 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
1029 # work with denormals and doesn't allow for the full swing in exponents
1030 # that you can get with normalized values. Instead, we create two powers
1031 # of two and multiply by them each in turn. That way the effective range
1032 # of our exponent is doubled.
1033 pow2_1 = fexp2i(('ishr', exp, 1), bits)
1034 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
1035 return ('fmul', ('fmul', f, pow2_1), pow2_2)
1036
1037 optimizations += [
1038 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
1039 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
1040 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
1041 ]
1042
1043 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
1044 def bitfield_reverse(u):
1045 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
1046 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
1047 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
1048 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
1049 step5 = ('ior', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
1050
1051 return step5
1052
1053 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
1054
1055 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
1056 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
1057 # and, if a is a NaN then the second comparison will fail anyway.
1058 for op in ['flt', 'fge', 'feq']:
1059 optimizations += [
1060 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
1061 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
1062 ]
1063
1064 # Add optimizations to handle the case where the result of a ternary is
1065 # compared to a constant. This way we can take things like
1066 #
1067 # (a ? 0 : 1) > 0
1068 #
1069 # and turn it into
1070 #
1071 # a ? (0 > 0) : (1 > 0)
1072 #
1073 # which constant folding will eat for lunch. The resulting ternary will
1074 # further get cleaned up by the boolean reductions above and we will be
1075 # left with just the original variable "a".
1076 for op in ['flt', 'fge', 'feq', 'fne',
1077 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
1078 optimizations += [
1079 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
1080 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
1081 ((op, '#d', ('bcsel', a, '#b', '#c')),
1082 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
1083 ]
1084
1085
1086 # For example, this converts things like
1087 #
1088 # 1 + mix(0, a - 1, condition)
1089 #
1090 # into
1091 #
1092 # mix(1, (a-1)+1, condition)
1093 #
1094 # Other optimizations will rearrange the constants.
1095 for op in ['fadd', 'fmul', 'iadd', 'imul']:
1096 optimizations += [
1097 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
1098 ]
1099
1100 # For derivatives in compute shaders, GLSL_NV_compute_shader_derivatives
1101 # states:
1102 #
1103 # If neither layout qualifier is specified, derivatives in compute shaders
1104 # return zero, which is consistent with the handling of built-in texture
1105 # functions like texture() in GLSL 4.50 compute shaders.
1106 for op in ['fddx', 'fddx_fine', 'fddx_coarse',
1107 'fddy', 'fddy_fine', 'fddy_coarse']:
1108 optimizations += [
1109 ((op, 'a'), 0.0, 'info->stage == MESA_SHADER_COMPUTE && info->cs.derivative_group == DERIVATIVE_GROUP_NONE')
1110 ]
1111
1112 # Some optimizations for ir3-specific instructions.
1113 optimizations += [
1114 # 'al * bl': If either 'al' or 'bl' is zero, return zero.
1115 (('umul_low', '#a(is_lower_half_zero)', 'b'), (0)),
1116 # '(ah * bl) << 16 + c': If either 'ah' or 'bl' is zero, return 'c'.
1117 (('imadsh_mix16', '#a@32(is_lower_half_zero)', 'b@32', 'c@32'), ('c')),
1118 (('imadsh_mix16', 'a@32', '#b@32(is_upper_half_zero)', 'c@32'), ('c')),
1119 ]
1120
1121 # This section contains "late" optimizations that should be run before
1122 # creating ffmas and calling regular optimizations for the final time.
1123 # Optimizations should go here if they help code generation and conflict
1124 # with the regular optimizations.
1125 before_ffma_optimizations = [
1126 # Propagate constants down multiplication chains
1127 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
1128 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
1129 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
1130 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
1131
1132 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
1133 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
1134 (('~fadd', ('fneg', a), a), 0.0),
1135 (('iadd', ('ineg', a), a), 0),
1136 (('iadd', ('ineg', a), ('iadd', a, b)), b),
1137 (('iadd', a, ('iadd', ('ineg', a), b)), b),
1138 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
1139 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
1140
1141 (('~flrp@32', ('fadd(is_used_once)', a, -1.0), ('fadd(is_used_once)', a, 1.0), d), ('fadd', ('flrp', -1.0, 1.0, d), a)),
1142 (('~flrp@32', ('fadd(is_used_once)', a, 1.0), ('fadd(is_used_once)', a, -1.0), d), ('fadd', ('flrp', 1.0, -1.0, d), a)),
1143 (('~flrp@32', ('fadd(is_used_once)', a, '#b'), ('fadd(is_used_once)', a, '#c'), d), ('fadd', ('fmul', d, ('fadd', c, ('fneg', b))), ('fadd', a, b))),
1144 ]
1145
1146 # This section contains "late" optimizations that should be run after the
1147 # regular optimizations have finished. Optimizations should go here if
1148 # they help code generation but do not necessarily produce code that is
1149 # more easily optimizable.
1150 late_optimizations = [
1151 # Most of these optimizations aren't quite safe when you get infinity or
1152 # Nan involved but the first one should be fine.
1153 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1154 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1155 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1156 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1157 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1158 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1159
1160 # nir_lower_to_source_mods will collapse this, but its existence during the
1161 # optimization loop can prevent other optimizations.
1162 (('fneg', ('fneg', a)), a),
1163
1164 # These are duplicated from the main optimizations table. The late
1165 # patterns that rearrange expressions like x - .5 < 0 to x < .5 can create
1166 # new patterns like these. The patterns that compare with zero are removed
1167 # because they are unlikely to be created in by anything in
1168 # late_optimizations.
1169 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
1170 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
1171 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
1172 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
1173 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
1174 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
1175
1176 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
1177 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
1178
1179 (('~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)))),
1180
1181 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
1182 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
1183 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
1184 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
1185 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
1186 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
1187 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
1188 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
1189 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
1190 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
1191
1192 (('ior', a, a), a),
1193 (('iand', a, a), a),
1194
1195 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
1196
1197 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1198 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1199 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1200 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1201
1202 (('~flrp@32', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1203 (('~flrp@64', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1204
1205 (('~fadd@32', 1.0, ('fmul(is_used_once)', c , ('fadd', b, -1.0 ))), ('fadd', ('fadd', 1.0, ('fneg', c)), ('fmul', b, c)), 'options->lower_flrp32'),
1206 (('~fadd@64', 1.0, ('fmul(is_used_once)', c , ('fadd', b, -1.0 ))), ('fadd', ('fadd', 1.0, ('fneg', c)), ('fmul', b, c)), 'options->lower_flrp64'),
1207
1208 # we do these late so that we don't get in the way of creating ffmas
1209 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1210 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1211
1212 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1213 ]
1214
1215 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1216 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1217 before_ffma_optimizations).render())
1218 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1219 late_optimizations).render())