nir/algebraic: add scmp algebraic optimizations
[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
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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 from math import pi
33
34 # Convenience variables
35 a = 'a'
36 b = 'b'
37 c = 'c'
38 d = 'd'
39 e = 'e'
40
41 # Written in the form (<search>, <replace>) where <search> is an expression
42 # and <replace> is either an expression or a value. An expression is
43 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
44 # where each source is either an expression or a value. A value can be
45 # either a numeric constant or a string representing a variable name.
46 #
47 # If the opcode in a search expression is prefixed by a '~' character, this
48 # indicates that the operation is inexact. Such operations will only get
49 # applied to SSA values that do not have the exact bit set. This should be
50 # used by by any optimizations that are not bit-for-bit exact. It should not,
51 # however, be used for backend-requested lowering operations as those need to
52 # happen regardless of precision.
53 #
54 # Variable names are specified as "[#]name[@type][(cond)][.swiz]" where:
55 # "#" indicates that the given variable will only match constants,
56 # type indicates that the given variable will only match values from ALU
57 # instructions with the given output type,
58 # (cond) specifies an additional condition function (see nir_search_helpers.h),
59 # swiz is a swizzle applied to the variable (only in the <replace> expression)
60 #
61 # For constants, you have to be careful to make sure that it is the right
62 # type because python is unaware of the source and destination types of the
63 # opcodes.
64 #
65 # All expression types can have a bit-size specified. For opcodes, this
66 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
67 # type and size. In the search half of the expression this indicates that it
68 # should only match that particular bit-size. In the replace half of the
69 # expression this indicates that the constructed value should have that
70 # bit-size.
71 #
72 # A special condition "many-comm-expr" can be used with expressions to note
73 # that the expression and its subexpressions have more commutative expressions
74 # than nir_replace_instr can handle. If this special condition is needed with
75 # another condition, the two can be separated by a comma (e.g.,
76 # "(many-comm-expr,is_used_once)").
77
78 # based on https://web.archive.org/web/20180105155939/http://forum.devmaster.net/t/fast-and-accurate-sine-cosine/9648
79 def lowered_sincos(c):
80 x = ('fsub', ('fmul', 2.0, ('ffract', ('fadd', ('fmul', 0.5 / pi, a), c))), 1.0)
81 x = ('fmul', ('fsub', x, ('fmul', x, ('fabs', x))), 4.0)
82 return ('ffma', ('ffma', x, ('fabs', x), ('fneg', x)), 0.225, x)
83
84 optimizations = [
85
86 (('imul', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b)), '!options->lower_bitshift'),
87 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitshift'),
88 (('ishl', a, '#b@32'), ('imul', a, ('ishl', 1, b)), 'options->lower_bitshift'),
89
90 (('unpack_64_2x32_split_x', ('imul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
91 (('unpack_64_2x32_split_x', ('umul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
92 (('imul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('imul_high', a, b)), 'options->lower_mul_2x32_64'),
93 (('umul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('umul_high', a, b)), 'options->lower_mul_2x32_64'),
94 (('udiv', a, 1), a),
95 (('idiv', a, 1), a),
96 (('umod', a, 1), 0),
97 (('imod', a, 1), 0),
98 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b)), '!options->lower_bitshift'),
99 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
100 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
101 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
102
103 (('fneg', ('fneg', a)), a),
104 (('ineg', ('ineg', a)), a),
105 (('fabs', ('fabs', a)), ('fabs', a)),
106 (('fabs', ('fneg', a)), ('fabs', a)),
107 (('fabs', ('u2f', a)), ('u2f', a)),
108 (('iabs', ('iabs', a)), ('iabs', a)),
109 (('iabs', ('ineg', a)), ('iabs', a)),
110 (('f2b', ('fneg', a)), ('f2b', a)),
111 (('i2b', ('ineg', a)), ('i2b', a)),
112 (('~fadd', a, 0.0), a),
113 (('iadd', a, 0), a),
114 (('usadd_4x8', a, 0), a),
115 (('usadd_4x8', a, ~0), ~0),
116 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
117 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
118 (('~fadd', ('fneg', a), a), 0.0),
119 (('iadd', ('ineg', a), a), 0),
120 (('iadd', ('ineg', a), ('iadd', a, b)), b),
121 (('iadd', a, ('iadd', ('ineg', a), b)), b),
122 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
123 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
124 (('fadd', ('fsat', a), ('fsat', ('fneg', a))), ('fsat', ('fabs', a))),
125 (('~fmul', a, 0.0), 0.0),
126 (('imul', a, 0), 0),
127 (('umul_unorm_4x8', a, 0), 0),
128 (('umul_unorm_4x8', a, ~0), a),
129 (('fmul', a, 1.0), a),
130 (('imul', a, 1), a),
131 (('fmul', a, -1.0), ('fneg', a)),
132 (('imul', a, -1), ('ineg', a)),
133 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
134 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
135 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
136 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
137 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
138 (('~ffma', 0.0, a, b), b),
139 (('~ffma', a, b, 0.0), ('fmul', a, b)),
140 (('ffma', 1.0, a, b), ('fadd', a, b)),
141 (('ffma', -1.0, a, b), ('fadd', ('fneg', a), b)),
142 (('~flrp', a, b, 0.0), a),
143 (('~flrp', a, b, 1.0), b),
144 (('~flrp', a, a, b), a),
145 (('~flrp', 0.0, a, b), ('fmul', a, b)),
146
147 # flrp(a, a + b, c) => a + flrp(0, b, c) => a + (b * c)
148 (('~flrp', a, ('fadd(is_used_once)', a, b), c), ('fadd', ('fmul', b, c), a)),
149 (('~flrp@32', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp32'),
150 (('~flrp@64', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp64'),
151
152 (('~flrp@32', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp32'),
153 (('~flrp@64', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp64'),
154
155 (('~flrp@32', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp32'),
156 (('~flrp@64', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp64'),
157
158 (('~flrp', ('fmul(is_used_once)', a, b), ('fmul(is_used_once)', a, c), d), ('fmul', ('flrp', b, c, d), a)),
159
160 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
161 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
162 (('ftrunc', a), ('bcsel', ('flt', a, 0.0), ('fneg', ('ffloor', ('fabs', a))), ('ffloor', ('fabs', a))), 'options->lower_ftrunc'),
163 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
164 (('fadd', a, ('fneg', ('ffract', a))), ('ffloor', a), '!options->lower_ffloor'),
165 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
166 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
167 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
168 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
169 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
170 # These are the same as the previous three rules, but it depends on
171 # 1-fsat(x) <=> fsat(1-x). See below.
172 (('~fadd@32', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp32'),
173 (('~fadd@64', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp64'),
174
175 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
176 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
177 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
178 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
179 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
180
181 (('~fmul', ('fadd', ('iand', ('ineg', ('b2i32', 'a@bool')), ('fmul', b, c)), '#d'), '#e'),
182 ('bcsel', a, ('fmul', ('fadd', ('fmul', b, c), d), e), ('fmul', d, e))),
183
184 (('fdph', a, b), ('fdot4', ('vec4', 'a.x', 'a.y', 'a.z', 1.0), b), 'options->lower_fdph'),
185
186 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d), '!options->lower_fdph'),
187 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
188 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
189 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
190
191 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
192 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
193
194 (('fdot2', ('vec2', a, 0.0), b), ('fmul', a, b)),
195 (('fdot2', a, 1.0), ('fadd', 'a.x', 'a.y')),
196
197 # If x >= 0 and x <= 1: fsat(1 - x) == 1 - fsat(x) trivially
198 # If x < 0: 1 - fsat(x) => 1 - 0 => 1 and fsat(1 - x) => fsat(> 1) => 1
199 # If x > 1: 1 - fsat(x) => 1 - 1 => 0 and fsat(1 - x) => fsat(< 0) => 0
200 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
201
202 # 1 - ((1 - a) * (1 - b))
203 # 1 - (1 - a - b + a*b)
204 # 1 - 1 + a + b - a*b
205 # a + b - a*b
206 # a + b*(1 - a)
207 # b*(1 - a) + 1*a
208 # flrp(b, 1, a)
209 (('~fadd@32', 1.0, ('fneg', ('fmul', ('fadd', 1.0, ('fneg', a)), ('fadd', 1.0, ('fneg', b))))),
210 ('flrp', b, 1.0, a), '!options->lower_flrp32'),
211
212 # (a * #b + #c) << #d
213 # ((a * #b) << #d) + (#c << #d)
214 # (a * (#b << #d)) + (#c << #d)
215 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
216 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
217
218 # (a * #b) << #c
219 # a * (#b << #c)
220 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
221
222 # Comparison simplifications
223 (('~inot', ('flt', a, b)), ('fge', a, b)),
224 (('~inot', ('fge', a, b)), ('flt', a, b)),
225 (('inot', ('feq', a, b)), ('fne', a, b)),
226 (('inot', ('fne', a, b)), ('feq', a, b)),
227 (('inot', ('ilt', a, b)), ('ige', a, b)),
228 (('inot', ('ult', a, b)), ('uge', a, b)),
229 (('inot', ('ige', a, b)), ('ilt', a, b)),
230 (('inot', ('uge', a, b)), ('ult', a, b)),
231 (('inot', ('ieq', a, b)), ('ine', a, b)),
232 (('inot', ('ine', a, b)), ('ieq', a, b)),
233
234 (('iand', ('feq', a, b), ('fne', a, b)), False),
235 (('iand', ('flt', a, b), ('flt', b, a)), False),
236 (('iand', ('ieq', a, b), ('ine', a, b)), False),
237 (('iand', ('ilt', a, b), ('ilt', b, a)), False),
238 (('iand', ('ult', a, b), ('ult', b, a)), False),
239
240 # This helps some shaders because, after some optimizations, they end up
241 # with patterns like (-a < -b) || (b < a). In an ideal world, this sort of
242 # matching would be handled by CSE.
243 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
244 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
245 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
246 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
247 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
248 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
249 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
250 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
251 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
252 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
253
254 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
255 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
256 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
257 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
258 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
259 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
260
261 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
262 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
263 (('fge', 0.0, ('fsat(is_used_once)', a)), ('fge', 0.0, a)),
264 (('flt', 0.0, ('fsat(is_used_once)', a)), ('flt', 0.0, a)),
265
266 # 0.0 >= b2f(a)
267 # b2f(a) <= 0.0
268 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
269 # inot(a)
270 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
271
272 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
273
274 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
275 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
276 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
277 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
278 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
279 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
280 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
281 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
282 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
283 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
284 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
285 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
286 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
287 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
288 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
289 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
290 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
291 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
292 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
293 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
294
295 # -(b2f(a) + b2f(b)) < 0
296 # 0 < b2f(a) + b2f(b)
297 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
298 # a || b
299 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
300 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
301
302 # -(b2f(a) + b2f(b)) >= 0
303 # 0 >= b2f(a) + b2f(b)
304 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
305 # !(a || b)
306 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
307 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
308
309 (('flt', a, ('fneg', a)), ('flt', a, 0.0)),
310 (('fge', a, ('fneg', a)), ('fge', a, 0.0)),
311
312 # Some optimizations (below) convert things like (a < b || c < b) into
313 # (min(a, c) < b). However, this interfers with the previous optimizations
314 # that try to remove comparisons with negated sums of b2f. This just
315 # breaks that apart.
316 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
317 ('ior', ('flt', c, 0.0), ('ior', a, b))),
318
319 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
320 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
321 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
322 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
323
324 # Cannot remove the addition from ilt or ige due to overflow.
325 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
326 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
327
328 # fmin(-b2f(a), b) >= 0.0
329 # -b2f(a) >= 0.0 && b >= 0.0
330 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
331 # b2f(a) == 0.0 && b >= 0.0
332 # a == False && b >= 0.0
333 # !a && b >= 0.0
334 #
335 # The fge in the second replacement is not a typo. I leave the proof that
336 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
337 # reader.
338 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
339 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
340
341 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
342 (('fne', ('b2f', 'a@1'), 0.0), a),
343 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
344 (('ine', ('b2i', 'a@1'), 0), a),
345
346 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
347 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
348 (('fge', ('u2f', a), 0.0), True),
349 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
350 (('flt', ('u2f', a), 0.0), False),
351 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
352 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
353 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
354 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
355 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
356 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
357 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
358
359 # 0.0 < fabs(a)
360 # fabs(a) > 0.0
361 # fabs(a) != 0.0 because fabs(a) must be >= 0
362 # a != 0.0
363 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
364
365 # -fabs(a) < 0.0
366 # fabs(a) > 0.0
367 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
368
369 # 0.0 >= fabs(a)
370 # 0.0 == fabs(a) because fabs(a) must be >= 0
371 # 0.0 == a
372 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
373
374 # -fabs(a) >= 0.0
375 # 0.0 >= fabs(a)
376 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
377
378 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
379 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
380 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
381 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
382
383 # fmin(b2f(a), b)
384 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
385 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
386 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
387 #
388 # Since b is a constant, constant folding will eliminate the fmin and the
389 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
390 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
391
392 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
393
394 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
395 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
396 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
397 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
398 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
399 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
400 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
401 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
402 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
403 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
404 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
405 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
406 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
407 (('bcsel', a, True, b), ('ior', a, b)),
408 (('bcsel', a, a, b), ('ior', a, b)),
409 (('bcsel', a, b, False), ('iand', a, b)),
410 (('bcsel', a, b, a), ('iand', a, b)),
411 (('fmin', a, a), a),
412 (('fmax', a, a), a),
413 (('imin', a, a), a),
414 (('imax', a, a), a),
415 (('umin', a, a), a),
416 (('umax', a, a), a),
417 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
418 (('umax', ('umax', a, b), b), ('umax', a, b)),
419 (('imax', ('imax', a, b), b), ('imax', a, b)),
420 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
421 (('umin', ('umin', a, b), b), ('umin', a, b)),
422 (('imin', ('imin', a, b), b), ('imin', a, b)),
423 (('fmax', a, ('fneg', a)), ('fabs', a)),
424 (('imax', a, ('ineg', a)), ('iabs', a)),
425 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
426 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
427 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
428 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
429 (('fmin', a, ('fabs', a)), a),
430 (('imin', a, ('iabs', a)), a),
431 (('fmax', a, ('fneg', ('fabs', a))), a),
432 (('imax', a, ('ineg', ('iabs', a))), a),
433 (('fmax', a, ('fabs', a)), ('fabs', a)),
434 (('imax', a, ('iabs', a)), ('iabs', a)),
435 (('fmax', a, ('fneg', a)), ('fabs', a)),
436 (('imax', a, ('ineg', a)), ('iabs', a)),
437 (('~fmax', ('fabs', a), 0.0), ('fabs', a)),
438 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
439 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
440 (('~fmin', ('fmax', a, -1.0), 0.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
441 (('~fmax', ('fmin', a, 0.0), -1.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_negate && !options->lower_fsat'),
442 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
443 (('fsat', ('b2f', a)), ('b2f', a)),
444 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
445 (('fsat', ('fsat', a)), ('fsat', a)),
446 (('fsat', ('fneg(is_used_once)', ('fadd(is_used_once)', a, b))), ('fsat', ('fadd', ('fneg', a), ('fneg', b))), '!options->lower_negate && !options->lower_fsat'),
447 (('fsat', ('fneg(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fneg', a), b)), '!options->lower_negate && !options->lower_fsat'),
448 (('fsat', ('fabs(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fabs', a), ('fabs', b))), '!options->lower_fsat'),
449 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
450 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
451 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
452 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
453 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
454 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
455 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
456 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
457 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
458 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
459 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
460 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
461 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
462 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
463 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
464 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
465 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
466 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
467 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
468 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
469 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
470 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
471
472 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
473 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
474 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
475 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
476 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
477 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
478 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
479 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
480 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
481 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
482 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
483 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
484 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
485 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
486 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
487 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
488
489 # Common pattern like 'if (i == 0 || i == 1 || ...)'
490 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
491 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
492 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
493
494 # The (i2f32, ...) part is an open-coded fsign. When that is combined with
495 # the bcsel, it's basically copysign(1.0, a). There is no copysign in NIR,
496 # so emit an open-coded version of that.
497 (('bcsel@32', ('feq', a, 0.0), 1.0, ('i2f32', ('iadd', ('b2i32', ('flt', 0.0, 'a@32')), ('ineg', ('b2i32', ('flt', 'a@32', 0.0)))))),
498 ('ior', 0x3f800000, ('iand', a, 0x80000000))),
499
500 (('ior', a, ('ieq', a, False)), True),
501 (('ior', a, ('inot', a)), -1),
502
503 (('ine', ('ineg', ('b2i32', 'a@1')), ('ineg', ('b2i32', 'b@1'))), ('ine', a, b)),
504 (('b2i32', ('ine', 'a@1', 'b@1')), ('b2i32', ('ixor', a, b))),
505
506 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0)),
507
508 # These patterns can result when (a < b || a < c) => (a < min(b, c))
509 # transformations occur before constant propagation and loop-unrolling.
510 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
511 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
512 (('~fge', a, ('fmin', b, a)), True),
513 (('~fge', ('fmax', a, b), a), True),
514 (('~flt', a, ('fmin', b, a)), False),
515 (('~flt', ('fmax', a, b), a), False),
516 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
517 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
518
519 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
520 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
521 (('ige', a, ('imin', b, a)), True),
522 (('ige', ('imax', a, b), a), True),
523 (('ult', a, ('umax', b, a)), ('ult', a, b)),
524 (('ult', ('umin', a, b), a), ('ult', b, a)),
525 (('uge', a, ('umin', b, a)), True),
526 (('uge', ('umax', a, b), a), True),
527 (('ilt', a, ('imin', b, a)), False),
528 (('ilt', ('imax', a, b), a), False),
529 (('ige', a, ('imax', b, a)), ('ige', a, b)),
530 (('ige', ('imin', a, b), a), ('ige', b, a)),
531 (('ult', a, ('umin', b, a)), False),
532 (('ult', ('umax', a, b), a), False),
533 (('uge', a, ('umax', b, a)), ('uge', a, b)),
534 (('uge', ('umin', a, b), a), ('uge', b, a)),
535 (('ult', a, ('iand', b, a)), False),
536 (('ult', ('ior', a, b), a), False),
537 (('uge', a, ('iand', b, a)), True),
538 (('uge', ('ior', a, b), a), True),
539
540 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
541 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
542 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
543 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
544 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
545 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
546 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
547 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
548 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
549 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
550 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
551 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
552 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
553 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
554 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
555 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
556
557 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
558 # negative.
559 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
560 ('iabs', ('ishr', a, b))),
561 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
562
563 (('fabs', ('slt', a, b)), ('slt', a, b)),
564 (('fabs', ('sge', a, b)), ('sge', a, b)),
565 (('fabs', ('seq', a, b)), ('seq', a, b)),
566 (('fabs', ('sne', a, b)), ('sne', a, b)),
567 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
568 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
569 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
570 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
571 (('seq', ('seq', a, b), 1.0), ('seq', a, b)),
572 (('seq', ('sne', a, b), 1.0), ('sne', a, b)),
573 (('seq', ('slt', a, b), 1.0), ('slt', a, b)),
574 (('seq', ('sge', a, b), 1.0), ('sge', a, b)),
575 (('sne', ('seq', a, b), 0.0), ('seq', a, b)),
576 (('sne', ('sne', a, b), 0.0), ('sne', a, b)),
577 (('sne', ('slt', a, b), 0.0), ('slt', a, b)),
578 (('sne', ('sge', a, b), 0.0), ('sge', a, b)),
579 (('seq', ('seq', a, b), 0.0), ('sne', a, b)),
580 (('seq', ('sne', a, b), 0.0), ('seq', a, b)),
581 (('seq', ('slt', a, b), 0.0), ('sge', a, b)),
582 (('seq', ('sge', a, b), 0.0), ('slt', a, b)),
583 (('sne', ('seq', a, b), 1.0), ('sne', a, b)),
584 (('sne', ('sne', a, b), 1.0), ('seq', a, b)),
585 (('sne', ('slt', a, b), 1.0), ('sge', a, b)),
586 (('sne', ('sge', a, b), 1.0), ('slt', a, b)),
587 (('fall_equal2', a, b), ('fmin', ('seq', 'a.x', 'b.x'), ('seq', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
588 (('fall_equal3', a, b), ('seq', ('fany_nequal3', a, b), 0.0), 'options->lower_vector_cmp'),
589 (('fall_equal4', a, b), ('seq', ('fany_nequal4', a, b), 0.0), 'options->lower_vector_cmp'),
590 (('fany_nequal2', a, b), ('fmax', ('sne', 'a.x', 'b.x'), ('sne', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
591 (('fany_nequal3', a, b), ('fsat', ('fdot3', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
592 (('fany_nequal4', a, b), ('fsat', ('fdot4', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
593 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
594 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
595 # Emulating booleans
596 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
597 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
598 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
599 (('iand', 'a@bool32', 1.0), ('b2f', a)),
600 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
601 (('ineg', ('b2i32', 'a@32')), a),
602 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
603 (('flt', ('fsub', 0.0, ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
604 # Comparison with the same args. Note that these are not done for
605 # the float versions because NaN always returns false on float
606 # inequalities.
607 (('ilt', a, a), False),
608 (('ige', a, a), True),
609 (('ieq', a, a), True),
610 (('ine', a, a), False),
611 (('ult', a, a), False),
612 (('uge', a, a), True),
613 # Logical and bit operations
614 (('iand', a, a), a),
615 (('iand', a, ~0), a),
616 (('iand', a, 0), 0),
617 (('ior', a, a), a),
618 (('ior', a, 0), a),
619 (('ior', a, True), True),
620 (('ixor', a, a), 0),
621 (('ixor', a, 0), a),
622 (('inot', ('inot', a)), a),
623 (('ior', ('iand', a, b), b), b),
624 (('ior', ('ior', a, b), b), ('ior', a, b)),
625 (('iand', ('ior', a, b), b), b),
626 (('iand', ('iand', a, b), b), ('iand', a, b)),
627 # DeMorgan's Laws
628 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
629 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
630 # Shift optimizations
631 (('ishl', 0, a), 0),
632 (('ishl', a, 0), a),
633 (('ishr', 0, a), 0),
634 (('ishr', a, 0), a),
635 (('ushr', 0, a), 0),
636 (('ushr', a, 0), a),
637 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
638 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
639 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('iadd', 16, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
640 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('isub', 16, b))), ('urol', a, b), '!options->lower_rotate'),
641 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('iadd', 32, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
642 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('isub', 32, b))), ('urol', a, b), '!options->lower_rotate'),
643 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('iadd', 16, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
644 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('isub', 16, b))), ('uror', a, b), '!options->lower_rotate'),
645 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('iadd', 32, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
646 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('isub', 32, b))), ('uror', a, b), '!options->lower_rotate'),
647 (('urol@16', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 16, b))), 'options->lower_rotate'),
648 (('urol@32', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 32, b))), 'options->lower_rotate'),
649 (('uror@16', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 16, b))), 'options->lower_rotate'),
650 (('uror@32', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 32, b))), 'options->lower_rotate'),
651 # Exponential/logarithmic identities
652 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
653 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
654 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
655 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
656 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
657 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
658 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
659 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
660 (('~fpow', a, 1.0), a),
661 (('~fpow', a, 2.0), ('fmul', a, a)),
662 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
663 (('~fpow', 2.0, a), ('fexp2', a)),
664 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
665 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
666 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
667 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
668 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
669 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
670 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
671 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
672 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
673 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
674 (('bcsel', ('flt', a, 0.0), 0.0, ('fsqrt', a)), ('fsqrt', ('fmax', a, 0.0))),
675 # Division and reciprocal
676 (('~fdiv', 1.0, a), ('frcp', a)),
677 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
678 (('~frcp', ('frcp', a)), a),
679 (('~frcp', ('fsqrt', a)), ('frsq', a)),
680 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
681 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
682 # Trig
683 (('fsin', a), lowered_sincos(0.5), 'options->lower_sincos'),
684 (('fcos', a), lowered_sincos(0.75), 'options->lower_sincos'),
685 # Boolean simplifications
686 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
687 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
688 (('ieq', a, True), a),
689 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
690 (('ine', a, False), a),
691 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
692 (('bcsel', a, True, False), a),
693 (('bcsel', a, False, True), ('inot', a)),
694 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
695 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
696 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
697 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
698 (('bcsel', True, b, c), b),
699 (('bcsel', False, b, c), c),
700 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
701
702 (('bcsel', a, b, b), b),
703 (('fcsel', a, b, b), b),
704
705 # D3D Boolean emulation
706 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
707 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
708 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
709 ('ineg', ('b2i', ('iand', a, b)))),
710 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
711 ('ineg', ('b2i', ('ior', a, b)))),
712 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
713 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
714 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
715 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
716 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
717
718 # SM5 32-bit shifts are defined to use the 5 least significant bits
719 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
720 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
721 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
722
723 # Conversions
724 (('i2b32', ('b2i', 'a@32')), a),
725 (('f2i', ('ftrunc', a)), ('f2i', a)),
726 (('f2u', ('ftrunc', a)), ('f2u', a)),
727 (('i2b', ('ineg', a)), ('i2b', a)),
728 (('i2b', ('iabs', a)), ('i2b', a)),
729 (('fabs', ('b2f', a)), ('b2f', a)),
730 (('iabs', ('b2i', a)), ('b2i', a)),
731 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
732
733 # Ironically, mark these as imprecise because removing the conversions may
734 # preserve more precision than doing the conversions (e.g.,
735 # uint(float(0x81818181u)) == 0x81818200).
736 (('~f2i32', ('i2f', 'a@32')), a),
737 (('~f2i32', ('u2f', 'a@32')), a),
738 (('~f2u32', ('i2f', 'a@32')), a),
739 (('~f2u32', ('u2f', 'a@32')), a),
740
741 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
742 # says:
743 #
744 # It is undefined to convert a negative floating-point value to an
745 # uint.
746 #
747 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
748 # some optimizations in the i965 backend to proceed.
749 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
750 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
751 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
752 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
753
754 (('~fmin', ('fabs', a), 1.0), ('fsat', ('fabs', a)), '!options->lower_fsat'),
755
756 # The result of the multiply must be in [-1, 0], so the result of the ffma
757 # must be in [0, 1].
758 (('flt', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), False),
759 (('flt', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), False),
760 (('fmax', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0)),
761 (('fmax', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0)),
762
763 # Packing and then unpacking does nothing
764 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
765 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
766 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
767 ('unpack_64_2x32_split_y', a)), a),
768
769 # Comparing two halves of an unpack separately. While this optimization
770 # should be correct for non-constant values, it's less obvious that it's
771 # useful in that case. For constant values, the pack will fold and we're
772 # guaranteed to reduce the whole tree to one instruction.
773 (('iand', ('ieq', ('unpack_32_2x16_split_x', a), '#b'),
774 ('ieq', ('unpack_32_2x16_split_y', a), '#c')),
775 ('ieq', a, ('pack_32_2x16_split', b, c))),
776
777 # Byte extraction
778 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
779 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
780 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
781 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
782 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
783 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
784 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte')
785 ]
786
787 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
788 # patterns like those below.
789 for op in ('ushr', 'ishr'):
790 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
791 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
792 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
793
794 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
795
796 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
797 # patterns like those below.
798 for op in ('extract_u8', 'extract_i8'):
799 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
800 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
801 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
802
803 optimizations.extend([
804 # Word extraction
805 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
806 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
807 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
808 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
809 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
810
811 # Subtracts
812 (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
813 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
814 (('ussub_4x8', a, 0), a),
815 (('ussub_4x8', a, ~0), 0),
816 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
817 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
818 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
819 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
820 (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
821 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
822 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
823 (('iabs', ('isub', 0, a)), ('iabs', a)),
824
825 # Propagate negation up multiplication chains
826 (('fmul(is_used_by_non_fsat)', ('fneg', a), b), ('fneg', ('fmul', a, b))),
827 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
828
829 # Propagate constants up multiplication chains
830 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
831 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
832 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
833 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
834
835 # Reassociate constants in add/mul chains so they can be folded together.
836 # For now, we mostly only handle cases where the constants are separated by
837 # a single non-constant. We could do better eventually.
838 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
839 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
840 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
841 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
842 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
843
844 # Drop mul-div by the same value when there's no wrapping.
845 (('idiv', ('imul(no_signed_wrap)', a, b), b), a),
846
847 # By definition...
848 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
849 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
850 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
851
852 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
853 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
854 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
855
856 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
857
858 # Misc. lowering
859 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
860 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
861 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
862 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
863 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
864
865 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
866 ('bcsel', ('ult', 31, 'bits'), 'insert',
867 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
868 'options->lower_bitfield_insert'),
869 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
870 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
871 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
872 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
873 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
874 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
875
876 # Alternative lowering that doesn't rely on bfi.
877 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
878 ('bcsel', ('ult', 31, 'bits'),
879 'insert',
880 (('ior',
881 ('iand', 'base', ('inot', ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))),
882 ('iand', ('ishl', 'insert', 'offset'), ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))))),
883 'options->lower_bitfield_insert_to_shifts'),
884
885 # Alternative lowering that uses bitfield_select.
886 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
887 ('bcsel', ('ult', 31, 'bits'), 'insert',
888 ('bitfield_select', ('bfm', 'bits', 'offset'), ('ishl', 'insert', 'offset'), 'base')),
889 'options->lower_bitfield_insert_to_bitfield_select'),
890
891 (('ibitfield_extract', 'value', 'offset', 'bits'),
892 ('bcsel', ('ult', 31, 'bits'), 'value',
893 ('ibfe', 'value', 'offset', 'bits')),
894 'options->lower_bitfield_extract'),
895
896 (('ubitfield_extract', 'value', 'offset', 'bits'),
897 ('bcsel', ('ult', 31, 'bits'), 'value',
898 ('ubfe', 'value', 'offset', 'bits')),
899 'options->lower_bitfield_extract'),
900
901 # Note that these opcodes are defined to only use the five least significant bits of 'offset' and 'bits'
902 (('ubfe', 'value', 'offset', ('iand', 31, 'bits')), ('ubfe', 'value', 'offset', 'bits')),
903 (('ubfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ubfe', 'value', 'offset', 'bits')),
904 (('ibfe', 'value', 'offset', ('iand', 31, 'bits')), ('ibfe', 'value', 'offset', 'bits')),
905 (('ibfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ibfe', 'value', 'offset', 'bits')),
906 (('bfm', 'bits', ('iand', 31, 'offset')), ('bfm', 'bits', 'offset')),
907 (('bfm', ('iand', 31, 'bits'), 'offset'), ('bfm', 'bits', 'offset')),
908
909 (('ibitfield_extract', 'value', 'offset', 'bits'),
910 ('bcsel', ('ieq', 0, 'bits'),
911 0,
912 ('ishr',
913 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
914 ('isub', 32, 'bits'))),
915 'options->lower_bitfield_extract_to_shifts'),
916
917 (('ubitfield_extract', 'value', 'offset', 'bits'),
918 ('iand',
919 ('ushr', 'value', 'offset'),
920 ('bcsel', ('ieq', 'bits', 32),
921 0xffffffff,
922 ('isub', ('ishl', 1, 'bits'), 1))),
923 'options->lower_bitfield_extract_to_shifts'),
924
925 (('ifind_msb', 'value'),
926 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
927 'options->lower_ifind_msb'),
928
929 (('find_lsb', 'value'),
930 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
931 'options->lower_find_lsb'),
932
933 (('extract_i8', a, 'b@32'),
934 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
935 'options->lower_extract_byte'),
936
937 (('extract_u8', a, 'b@32'),
938 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
939 'options->lower_extract_byte'),
940
941 (('extract_i16', a, 'b@32'),
942 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
943 'options->lower_extract_word'),
944
945 (('extract_u16', a, 'b@32'),
946 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
947 'options->lower_extract_word'),
948
949 (('pack_unorm_2x16', 'v'),
950 ('pack_uvec2_to_uint',
951 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
952 'options->lower_pack_unorm_2x16'),
953
954 (('pack_unorm_4x8', 'v'),
955 ('pack_uvec4_to_uint',
956 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
957 'options->lower_pack_unorm_4x8'),
958
959 (('pack_snorm_2x16', 'v'),
960 ('pack_uvec2_to_uint',
961 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
962 'options->lower_pack_snorm_2x16'),
963
964 (('pack_snorm_4x8', 'v'),
965 ('pack_uvec4_to_uint',
966 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
967 'options->lower_pack_snorm_4x8'),
968
969 (('unpack_unorm_2x16', 'v'),
970 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
971 ('extract_u16', 'v', 1))),
972 65535.0),
973 'options->lower_unpack_unorm_2x16'),
974
975 (('unpack_unorm_4x8', 'v'),
976 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
977 ('extract_u8', 'v', 1),
978 ('extract_u8', 'v', 2),
979 ('extract_u8', 'v', 3))),
980 255.0),
981 'options->lower_unpack_unorm_4x8'),
982
983 (('unpack_snorm_2x16', 'v'),
984 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
985 ('extract_i16', 'v', 1))),
986 32767.0))),
987 'options->lower_unpack_snorm_2x16'),
988
989 (('unpack_snorm_4x8', 'v'),
990 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
991 ('extract_i8', 'v', 1),
992 ('extract_i8', 'v', 2),
993 ('extract_i8', 'v', 3))),
994 127.0))),
995 'options->lower_unpack_snorm_4x8'),
996
997 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
998 (('fsign', a), ('fsub', ('b2f', ('flt', 0.0, a)), ('b2f', ('flt', a, 0.0))), 'options->lower_fsign'),
999 ])
1000
1001 # bit_size dependent lowerings
1002 for bit_size in [8, 16, 32, 64]:
1003 # convenience constants
1004 intmax = (1 << (bit_size - 1)) - 1
1005 intmin = 1 << (bit_size - 1)
1006
1007 optimizations += [
1008 (('iadd_sat@' + str(bit_size), a, b),
1009 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
1010 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
1011 (('isub_sat@' + str(bit_size), a, b),
1012 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
1013 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
1014 ]
1015
1016 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')])
1017
1018 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
1019 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
1020 ('iand', (invert[left], a, b), (invert[right], c, d))))
1021 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
1022 ('ior', (invert[left], a, b), (invert[right], c, d))))
1023
1024 # Optimize x2bN(b2x(x)) -> x
1025 for size in type_sizes('bool'):
1026 aN = 'a@' + str(size)
1027 f2bN = 'f2b' + str(size)
1028 i2bN = 'i2b' + str(size)
1029 optimizations.append(((f2bN, ('b2f', aN)), a))
1030 optimizations.append(((i2bN, ('b2i', aN)), a))
1031
1032 # Optimize x2yN(b2x(x)) -> b2y
1033 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
1034 if x != 'f' and y != 'f' and x != y:
1035 continue
1036
1037 b2x = 'b2f' if x == 'f' else 'b2i'
1038 b2y = 'b2f' if y == 'f' else 'b2i'
1039 x2yN = '{}2{}'.format(x, y)
1040 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
1041
1042 # Optimize away x2xN(a@N)
1043 for t in ['int', 'uint', 'float']:
1044 for N in type_sizes(t):
1045 x2xN = '{0}2{0}{1}'.format(t[0], N)
1046 aN = 'a@{0}'.format(N)
1047 optimizations.append(((x2xN, aN), a))
1048
1049 # Optimize x2xN(y2yM(a@P)) -> y2yN(a) for integers
1050 # In particular, we can optimize away everything except upcast of downcast and
1051 # upcasts where the type differs from the other cast
1052 for N, M in itertools.product(type_sizes('uint'), type_sizes('uint')):
1053 if N < M:
1054 # The outer cast is a down-cast. It doesn't matter what the size of the
1055 # argument of the inner cast is because we'll never been in the upcast
1056 # of downcast case. Regardless of types, we'll always end up with y2yN
1057 # in the end.
1058 for x, y in itertools.product(['i', 'u'], ['i', 'u']):
1059 x2xN = '{0}2{0}{1}'.format(x, N)
1060 y2yM = '{0}2{0}{1}'.format(y, M)
1061 y2yN = '{0}2{0}{1}'.format(y, N)
1062 optimizations.append(((x2xN, (y2yM, a)), (y2yN, a)))
1063 elif N > M:
1064 # If the outer cast is an up-cast, we have to be more careful about the
1065 # size of the argument of the inner cast and with types. In this case,
1066 # the type is always the type of type up-cast which is given by the
1067 # outer cast.
1068 for P in type_sizes('uint'):
1069 # We can't optimize away up-cast of down-cast.
1070 if M < P:
1071 continue
1072
1073 # Because we're doing down-cast of down-cast, the types always have
1074 # to match between the two casts
1075 for x in ['i', 'u']:
1076 x2xN = '{0}2{0}{1}'.format(x, N)
1077 x2xM = '{0}2{0}{1}'.format(x, M)
1078 aP = 'a@{0}'.format(P)
1079 optimizations.append(((x2xN, (x2xM, aP)), (x2xN, a)))
1080 else:
1081 # The N == M case is handled by other optimizations
1082 pass
1083
1084 # Optimize comparisons with up-casts
1085 for t in ['int', 'uint', 'float']:
1086 for N, M in itertools.product(type_sizes(t), repeat=2):
1087 if N == 1 or N >= M:
1088 continue
1089
1090 x2xM = '{0}2{0}{1}'.format(t[0], M)
1091 x2xN = '{0}2{0}{1}'.format(t[0], N)
1092 aN = 'a@' + str(N)
1093 bN = 'b@' + str(N)
1094 xeq = 'feq' if t == 'float' else 'ieq'
1095 xne = 'fne' if t == 'float' else 'ine'
1096 xge = '{0}ge'.format(t[0])
1097 xlt = '{0}lt'.format(t[0])
1098
1099 # Up-casts are lossless so for correctly signed comparisons of
1100 # up-casted values we can do the comparison at the largest of the two
1101 # original sizes and drop one or both of the casts. (We have
1102 # optimizations to drop the no-op casts which this may generate.)
1103 for P in type_sizes(t):
1104 if P == 1 or P > N:
1105 continue
1106
1107 bP = 'b@' + str(P)
1108 optimizations += [
1109 ((xeq, (x2xM, aN), (x2xM, bP)), (xeq, a, (x2xN, b))),
1110 ((xne, (x2xM, aN), (x2xM, bP)), (xne, a, (x2xN, b))),
1111 ((xge, (x2xM, aN), (x2xM, bP)), (xge, a, (x2xN, b))),
1112 ((xlt, (x2xM, aN), (x2xM, bP)), (xlt, a, (x2xN, b))),
1113 ((xge, (x2xM, bP), (x2xM, aN)), (xge, (x2xN, b), a)),
1114 ((xlt, (x2xM, bP), (x2xM, aN)), (xlt, (x2xN, b), a)),
1115 ]
1116
1117 # The next bit doesn't work on floats because the range checks would
1118 # get way too complicated.
1119 if t in ['int', 'uint']:
1120 if t == 'int':
1121 xN_min = -(1 << (N - 1))
1122 xN_max = (1 << (N - 1)) - 1
1123 elif t == 'uint':
1124 xN_min = 0
1125 xN_max = (1 << N) - 1
1126 else:
1127 assert False
1128
1129 # If we're up-casting and comparing to a constant, we can unfold
1130 # the comparison into a comparison with the shrunk down constant
1131 # and a check that the constant fits in the smaller bit size.
1132 optimizations += [
1133 ((xeq, (x2xM, aN), '#b'),
1134 ('iand', (xeq, a, (x2xN, b)), (xeq, (x2xM, (x2xN, b)), b))),
1135 ((xne, (x2xM, aN), '#b'),
1136 ('ior', (xne, a, (x2xN, b)), (xne, (x2xM, (x2xN, b)), b))),
1137 ((xlt, (x2xM, aN), '#b'),
1138 ('iand', (xlt, xN_min, b),
1139 ('ior', (xlt, xN_max, b), (xlt, a, (x2xN, b))))),
1140 ((xlt, '#a', (x2xM, bN)),
1141 ('iand', (xlt, a, xN_max),
1142 ('ior', (xlt, a, xN_min), (xlt, (x2xN, a), b)))),
1143 ((xge, (x2xM, aN), '#b'),
1144 ('iand', (xge, xN_max, b),
1145 ('ior', (xge, xN_min, b), (xge, a, (x2xN, b))))),
1146 ((xge, '#a', (x2xM, bN)),
1147 ('iand', (xge, a, xN_min),
1148 ('ior', (xge, a, xN_max), (xge, (x2xN, a), b)))),
1149 ]
1150
1151 def fexp2i(exp, bits):
1152 # We assume that exp is already in the right range.
1153 if bits == 16:
1154 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
1155 elif bits == 32:
1156 return ('ishl', ('iadd', exp, 127), 23)
1157 elif bits == 64:
1158 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
1159 else:
1160 assert False
1161
1162 def ldexp(f, exp, bits):
1163 # First, we clamp exp to a reasonable range. The maximum possible range
1164 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
1165 # a maximum range of [-149, 127]. This means that we can potentially have
1166 # a swing of +-276. If you start with FLT_MAX, you actually have to do
1167 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
1168 # spec, on the other hand, only requires that we handle an exponent value
1169 # in the range [-126, 128]. This implementation is *mostly* correct; it
1170 # handles a range on exp of [-252, 254] which allows you to create any
1171 # value (including denorms if the hardware supports it) and to adjust the
1172 # exponent of any normal value to anything you want.
1173 if bits == 16:
1174 exp = ('imin', ('imax', exp, -28), 30)
1175 elif bits == 32:
1176 exp = ('imin', ('imax', exp, -252), 254)
1177 elif bits == 64:
1178 exp = ('imin', ('imax', exp, -2044), 2046)
1179 else:
1180 assert False
1181
1182 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
1183 # (We use ishr which isn't the same for -1, but the -1 case still works
1184 # since we use exp-exp/2 as the second exponent.) While the spec
1185 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
1186 # work with denormals and doesn't allow for the full swing in exponents
1187 # that you can get with normalized values. Instead, we create two powers
1188 # of two and multiply by them each in turn. That way the effective range
1189 # of our exponent is doubled.
1190 pow2_1 = fexp2i(('ishr', exp, 1), bits)
1191 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
1192 return ('fmul', ('fmul', f, pow2_1), pow2_2)
1193
1194 optimizations += [
1195 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
1196 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
1197 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
1198 ]
1199
1200 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
1201 def bitfield_reverse(u):
1202 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
1203 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
1204 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
1205 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
1206 step5 = ('ior(many-comm-expr)', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
1207
1208 return step5
1209
1210 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
1211
1212 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
1213 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
1214 # and, if a is a NaN then the second comparison will fail anyway.
1215 for op in ['flt', 'fge', 'feq']:
1216 optimizations += [
1217 (('iand', ('feq', a, a), (op, a, b)), (op, a, b)),
1218 (('iand', ('feq', a, a), (op, b, a)), (op, b, a)),
1219 ]
1220
1221 # Add optimizations to handle the case where the result of a ternary is
1222 # compared to a constant. This way we can take things like
1223 #
1224 # (a ? 0 : 1) > 0
1225 #
1226 # and turn it into
1227 #
1228 # a ? (0 > 0) : (1 > 0)
1229 #
1230 # which constant folding will eat for lunch. The resulting ternary will
1231 # further get cleaned up by the boolean reductions above and we will be
1232 # left with just the original variable "a".
1233 for op in ['flt', 'fge', 'feq', 'fne',
1234 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
1235 optimizations += [
1236 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
1237 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
1238 ((op, '#d', ('bcsel', a, '#b', '#c')),
1239 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
1240 ]
1241
1242
1243 # For example, this converts things like
1244 #
1245 # 1 + mix(0, a - 1, condition)
1246 #
1247 # into
1248 #
1249 # mix(1, (a-1)+1, condition)
1250 #
1251 # Other optimizations will rearrange the constants.
1252 for op in ['fadd', 'fmul', 'iadd', 'imul']:
1253 optimizations += [
1254 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
1255 ]
1256
1257 # For derivatives in compute shaders, GLSL_NV_compute_shader_derivatives
1258 # states:
1259 #
1260 # If neither layout qualifier is specified, derivatives in compute shaders
1261 # return zero, which is consistent with the handling of built-in texture
1262 # functions like texture() in GLSL 4.50 compute shaders.
1263 for op in ['fddx', 'fddx_fine', 'fddx_coarse',
1264 'fddy', 'fddy_fine', 'fddy_coarse']:
1265 optimizations += [
1266 ((op, 'a'), 0.0, 'info->stage == MESA_SHADER_COMPUTE && info->cs.derivative_group == DERIVATIVE_GROUP_NONE')
1267 ]
1268
1269 # Some optimizations for ir3-specific instructions.
1270 optimizations += [
1271 # 'al * bl': If either 'al' or 'bl' is zero, return zero.
1272 (('umul_low', '#a(is_lower_half_zero)', 'b'), (0)),
1273 # '(ah * bl) << 16 + c': If either 'ah' or 'bl' is zero, return 'c'.
1274 (('imadsh_mix16', '#a@32(is_lower_half_zero)', 'b@32', 'c@32'), ('c')),
1275 (('imadsh_mix16', 'a@32', '#b@32(is_upper_half_zero)', 'c@32'), ('c')),
1276 ]
1277
1278 # This section contains "late" optimizations that should be run before
1279 # creating ffmas and calling regular optimizations for the final time.
1280 # Optimizations should go here if they help code generation and conflict
1281 # with the regular optimizations.
1282 before_ffma_optimizations = [
1283 # Propagate constants down multiplication chains
1284 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
1285 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
1286 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
1287 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
1288
1289 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
1290 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
1291 (('~fadd', ('fneg', a), a), 0.0),
1292 (('iadd', ('ineg', a), a), 0),
1293 (('iadd', ('ineg', a), ('iadd', a, b)), b),
1294 (('iadd', a, ('iadd', ('ineg', a), b)), b),
1295 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
1296 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
1297
1298 (('~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)),
1299 (('~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)),
1300 (('~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))),
1301 ]
1302
1303 # This section contains "late" optimizations that should be run after the
1304 # regular optimizations have finished. Optimizations should go here if
1305 # they help code generation but do not necessarily produce code that is
1306 # more easily optimizable.
1307 late_optimizations = [
1308 # Most of these optimizations aren't quite safe when you get infinity or
1309 # Nan involved but the first one should be fine.
1310 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1311 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1312 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1313 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1314 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1315 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1316
1317 # nir_lower_to_source_mods will collapse this, but its existence during the
1318 # optimization loop can prevent other optimizations.
1319 (('fneg', ('fneg', a)), a),
1320
1321 # These are duplicated from the main optimizations table. The late
1322 # patterns that rearrange expressions like x - .5 < 0 to x < .5 can create
1323 # new patterns like these. The patterns that compare with zero are removed
1324 # because they are unlikely to be created in by anything in
1325 # late_optimizations.
1326 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
1327 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
1328 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
1329 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
1330 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
1331 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
1332
1333 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
1334 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
1335
1336 (('~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)))),
1337
1338 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
1339 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
1340 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
1341 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
1342 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
1343 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
1344 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
1345 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
1346 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
1347 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
1348
1349 (('ior', a, a), a),
1350 (('iand', a, a), a),
1351
1352 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
1353
1354 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1355 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1356 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1357 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1358
1359 (('~flrp@32', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1360 (('~flrp@64', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1361
1362 (('~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'),
1363 (('~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'),
1364
1365 # A similar operation could apply to any ffma(#a, b, #(-a/2)), but this
1366 # particular operation is common for expanding values stored in a texture
1367 # from [0,1] to [-1,1].
1368 (('~ffma@32', a, 2.0, -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1369 (('~ffma@32', a, -2.0, -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1370 (('~ffma@32', a, -2.0, 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1371 (('~ffma@32', a, 2.0, 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1372 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1373 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1374 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1375 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1376
1377 # flrp(a, b, a)
1378 # a*(1-a) + b*a
1379 # a + -a*a + a*b (1)
1380 # a + a*(b - a)
1381 # Option 1: ffma(a, (b-a), a)
1382 #
1383 # Alternately, after (1):
1384 # a*(1+b) + -a*a
1385 # a*((1+b) + -a)
1386 #
1387 # Let b=1
1388 #
1389 # Option 2: ffma(a, 2, -(a*a))
1390 # Option 3: ffma(a, 2, (-a)*a)
1391 # Option 4: ffma(a, -a, (2*a)
1392 # Option 5: a * (2 - a)
1393 #
1394 # There are a lot of other possible combinations.
1395 (('~ffma@32', ('fadd', b, ('fneg', a)), a, a), ('flrp', a, b, a), '!options->lower_flrp32'),
1396 (('~ffma@32', a, 2.0, ('fneg', ('fmul', a, a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1397 (('~ffma@32', a, 2.0, ('fmul', ('fneg', a), a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1398 (('~ffma@32', a, ('fneg', a), ('fmul', 2.0, a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1399 (('~fmul@32', a, ('fadd', 2.0, ('fneg', a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1400
1401 # we do these late so that we don't get in the way of creating ffmas
1402 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1403 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1404
1405 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1406
1407 # Things that look like DPH in the source shader may get expanded to
1408 # something that looks like dot(v1.xyz, v2.xyz) + v1.w by the time it gets
1409 # to NIR. After FFMA is generated, this can look like:
1410 #
1411 # fadd(ffma(v1.z, v2.z, ffma(v1.y, v2.y, fmul(v1.x, v2.x))), v1.w)
1412 #
1413 # Reassociate the last addition into the first multiplication.
1414 (('~fadd', ('ffma(is_used_once)', a, b, ('ffma', c, d, ('fmul', 'e(is_not_const_and_not_fsign)', 'f(is_not_const_and_not_fsign)'))), 'g(is_not_const)'),
1415 ('ffma', a, b, ('ffma', c, d, ('ffma', e, 'f', 'g'))), '!options->intel_vec4'),
1416 (('~fadd', ('ffma(is_used_once)', a, b, ('fmul', 'e(is_not_const_and_not_fsign)', 'f(is_not_const_and_not_fsign)') ), 'g(is_not_const)'),
1417 ('ffma', a, b, ('ffma', e, 'f', 'g') ), '!options->intel_vec4'),
1418 ]
1419
1420 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1421 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1422 before_ffma_optimizations).render())
1423 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1424 late_optimizations).render())