5e586a303deb866fb2992a84f812098d38707029
[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 import struct
33 from math import pi
34
35 # Convenience variables
36 a = 'a'
37 b = 'b'
38 c = 'c'
39 d = 'd'
40 e = 'e'
41
42 # Written in the form (<search>, <replace>) where <search> is an expression
43 # and <replace> is either an expression or a value. An expression is
44 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
45 # where each source is either an expression or a value. A value can be
46 # either a numeric constant or a string representing a variable name.
47 #
48 # If the opcode in a search expression is prefixed by a '~' character, this
49 # indicates that the operation is inexact. Such operations will only get
50 # applied to SSA values that do not have the exact bit set. This should be
51 # used by by any optimizations that are not bit-for-bit exact. It should not,
52 # however, be used for backend-requested lowering operations as those need to
53 # happen regardless of precision.
54 #
55 # Variable names are specified as "[#]name[@type][(cond)][.swiz]" where:
56 # "#" indicates that the given variable will only match constants,
57 # type indicates that the given variable will only match values from ALU
58 # instructions with the given output type,
59 # (cond) specifies an additional condition function (see nir_search_helpers.h),
60 # swiz is a swizzle applied to the variable (only in the <replace> expression)
61 #
62 # For constants, you have to be careful to make sure that it is the right
63 # type because python is unaware of the source and destination types of the
64 # opcodes.
65 #
66 # All expression types can have a bit-size specified. For opcodes, this
67 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
68 # type and size. In the search half of the expression this indicates that it
69 # should only match that particular bit-size. In the replace half of the
70 # expression this indicates that the constructed value should have that
71 # bit-size.
72 #
73 # If the opcode in a replacement expression is prefixed by a '!' character,
74 # this indicated that the new expression will be marked exact.
75 #
76 # A special condition "many-comm-expr" can be used with expressions to note
77 # that the expression and its subexpressions have more commutative expressions
78 # than nir_replace_instr can handle. If this special condition is needed with
79 # another condition, the two can be separated by a comma (e.g.,
80 # "(many-comm-expr,is_used_once)").
81
82 # based on https://web.archive.org/web/20180105155939/http://forum.devmaster.net/t/fast-and-accurate-sine-cosine/9648
83 def lowered_sincos(c):
84 x = ('fsub', ('fmul', 2.0, ('ffract', ('fadd', ('fmul', 0.5 / pi, a), c))), 1.0)
85 x = ('fmul', ('fsub', x, ('fmul', x, ('fabs', x))), 4.0)
86 return ('ffma', ('ffma', x, ('fabs', x), ('fneg', x)), 0.225, x)
87
88 def intBitsToFloat(i):
89 return struct.unpack('!f', struct.pack('!I', i))[0]
90
91 optimizations = [
92
93 (('imul', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b)), '!options->lower_bitops'),
94 (('imul', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitops'),
95 (('ishl', a, '#b@32'), ('imul', a, ('ishl', 1, b)), 'options->lower_bitops'),
96
97 (('unpack_64_2x32_split_x', ('imul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
98 (('unpack_64_2x32_split_x', ('umul_2x32_64(is_used_once)', a, b)), ('imul', a, b)),
99 (('imul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('imul_high', a, b)), 'options->lower_mul_2x32_64'),
100 (('umul_2x32_64', a, b), ('pack_64_2x32_split', ('imul', a, b), ('umul_high', a, b)), 'options->lower_mul_2x32_64'),
101 (('udiv', a, 1), a),
102 (('idiv', a, 1), a),
103 (('umod', a, 1), 0),
104 (('imod', a, 1), 0),
105 (('udiv', a, '#b@32(is_pos_power_of_two)'), ('ushr', a, ('find_lsb', b)), '!options->lower_bitops'),
106 (('idiv', a, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', b))), 'options->lower_idiv'),
107 (('idiv', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a), ('ushr', ('iabs', a), ('find_lsb', ('iabs', b))))), 'options->lower_idiv'),
108 (('umod', a, '#b(is_pos_power_of_two)'), ('iand', a, ('isub', b, 1))),
109
110 (('~fneg', ('fneg', a)), a),
111 (('ineg', ('ineg', a)), a),
112 (('fabs', ('fabs', a)), ('fabs', a)),
113 (('fabs', ('fneg', a)), ('fabs', a)),
114 (('fabs', ('u2f', a)), ('u2f', a)),
115 (('iabs', ('iabs', a)), ('iabs', a)),
116 (('iabs', ('ineg', a)), ('iabs', a)),
117 (('f2b', ('fneg', a)), ('f2b', a)),
118 (('i2b', ('ineg', a)), ('i2b', a)),
119 (('~fadd', a, 0.0), a),
120 (('iadd', a, 0), a),
121 (('usadd_4x8', a, 0), a),
122 (('usadd_4x8', a, ~0), ~0),
123 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
124 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
125 (('~fadd', ('fneg', a), a), 0.0),
126 (('iadd', ('ineg', a), a), 0),
127 (('iadd', ('ineg', a), ('iadd', a, b)), b),
128 (('iadd', a, ('iadd', ('ineg', a), b)), b),
129 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
130 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
131 (('fadd', ('fsat', a), ('fsat', ('fneg', a))), ('fsat', ('fabs', a))),
132 (('~fmul', a, 0.0), 0.0),
133 (('imul', a, 0), 0),
134 (('umul_unorm_4x8', a, 0), 0),
135 (('umul_unorm_4x8', a, ~0), a),
136 (('~fmul', a, 1.0), a),
137 (('imul', a, 1), a),
138 (('fmul', a, -1.0), ('fneg', a)),
139 (('imul', a, -1), ('ineg', a)),
140 # If a < 0: fsign(a)*a*a => -1*a*a => -a*a => abs(a)*a
141 # If a > 0: fsign(a)*a*a => 1*a*a => a*a => abs(a)*a
142 # If a == 0: fsign(a)*a*a => 0*0*0 => abs(0)*0
143 (('fmul', ('fsign', a), ('fmul', a, a)), ('fmul', ('fabs', a), a)),
144 (('fmul', ('fmul', ('fsign', a), a), a), ('fmul', ('fabs', a), a)),
145 (('~ffma', 0.0, a, b), b),
146 (('~ffma', a, b, 0.0), ('fmul', a, b)),
147 (('ffma', 1.0, a, b), ('fadd', a, b)),
148 (('ffma', -1.0, a, b), ('fadd', ('fneg', a), b)),
149 (('~flrp', a, b, 0.0), a),
150 (('~flrp', a, b, 1.0), b),
151 (('~flrp', a, a, b), a),
152 (('~flrp', 0.0, a, b), ('fmul', a, b)),
153
154 # flrp(a, a + b, c) => a + flrp(0, b, c) => a + (b * c)
155 (('~flrp', a, ('fadd(is_used_once)', a, b), c), ('fadd', ('fmul', b, c), a)),
156 (('~flrp@32', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp32'),
157 (('~flrp@64', a, ('fadd', a, b), c), ('fadd', ('fmul', b, c), a), 'options->lower_flrp64'),
158
159 (('~flrp@32', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp32'),
160 (('~flrp@64', ('fadd', a, b), ('fadd', a, c), d), ('fadd', ('flrp', b, c, d), a), 'options->lower_flrp64'),
161
162 (('~flrp@32', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp32'),
163 (('~flrp@64', a, ('fmul(is_used_once)', a, b), c), ('fmul', ('flrp', 1.0, b, c), a), 'options->lower_flrp64'),
164
165 (('~flrp', ('fmul(is_used_once)', a, b), ('fmul(is_used_once)', a, c), d), ('fmul', ('flrp', b, c, d), a)),
166
167 (('~flrp', a, b, ('b2f', 'c@1')), ('bcsel', c, b, a), 'options->lower_flrp32'),
168 (('~flrp', a, 0.0, c), ('fadd', ('fmul', ('fneg', a), c), a)),
169 (('ftrunc', a), ('bcsel', ('flt', a, 0.0), ('fneg', ('ffloor', ('fabs', a))), ('ffloor', ('fabs', a))), 'options->lower_ftrunc'),
170 (('ffloor', a), ('fsub', a, ('ffract', a)), 'options->lower_ffloor'),
171 (('fadd', a, ('fneg', ('ffract', a))), ('ffloor', a), '!options->lower_ffloor'),
172 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
173 (('fceil', a), ('fneg', ('ffloor', ('fneg', a))), 'options->lower_fceil'),
174 (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', 'c@1')))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp32'),
175 (('~fadd@32', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp32'),
176 (('~fadd@64', ('fmul', a, ('fadd', 1.0, ('fneg', c ) )), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp64'),
177 # These are the same as the previous three rules, but it depends on
178 # 1-fsat(x) <=> fsat(1-x). See below.
179 (('~fadd@32', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp32'),
180 (('~fadd@64', ('fmul', a, ('fsat', ('fadd', 1.0, ('fneg', c )))), ('fmul', b, ('fsat', c))), ('flrp', a, b, ('fsat', c)), '!options->lower_flrp64'),
181
182 (('~fadd', a, ('fmul', ('b2f', 'c@1'), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp32'),
183 (('~fadd@32', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp32'),
184 (('~fadd@64', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp64'),
185 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
186 (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), 'options->fuse_ffma'),
187
188 (('~fmul', ('fadd', ('iand', ('ineg', ('b2i32', 'a@bool')), ('fmul', b, c)), '#d'), '#e'),
189 ('bcsel', a, ('fmul', ('fadd', ('fmul', b, c), d), e), ('fmul', d, e))),
190
191 (('fdph', a, b), ('fdot4', ('vec4', 'a.x', 'a.y', 'a.z', 1.0), b), 'options->lower_fdph'),
192
193 (('fdot4', ('vec4', a, b, c, 1.0), d), ('fdph', ('vec3', a, b, c), d), '!options->lower_fdph'),
194 (('fdot4', ('vec4', a, 0.0, 0.0, 0.0), b), ('fmul', a, b)),
195 (('fdot4', ('vec4', a, b, 0.0, 0.0), c), ('fdot2', ('vec2', a, b), c)),
196 (('fdot4', ('vec4', a, b, c, 0.0), d), ('fdot3', ('vec3', a, b, c), d)),
197
198 (('fdot3', ('vec3', a, 0.0, 0.0), b), ('fmul', a, b)),
199 (('fdot3', ('vec3', a, b, 0.0), c), ('fdot2', ('vec2', a, b), c)),
200
201 (('fdot2', ('vec2', a, 0.0), b), ('fmul', a, b)),
202 (('fdot2', a, 1.0), ('fadd', 'a.x', 'a.y')),
203
204 # Lower fdot to fsum when it is available
205 (('fdot2', a, b), ('fsum2', ('fmul', a, b)), 'options->lower_fdot'),
206 (('fdot3', a, b), ('fsum3', ('fmul', a, b)), 'options->lower_fdot'),
207 (('fdot4', a, b), ('fsum4', ('fmul', a, b)), 'options->lower_fdot'),
208 (('fsum2', a), ('fadd', 'a.x', 'a.y'), 'options->lower_fdot'),
209
210 # If x >= 0 and x <= 1: fsat(1 - x) == 1 - fsat(x) trivially
211 # If x < 0: 1 - fsat(x) => 1 - 0 => 1 and fsat(1 - x) => fsat(> 1) => 1
212 # If x > 1: 1 - fsat(x) => 1 - 1 => 0 and fsat(1 - x) => fsat(< 0) => 0
213 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
214
215 # 1 - ((1 - a) * (1 - b))
216 # 1 - (1 - a - b + a*b)
217 # 1 - 1 + a + b - a*b
218 # a + b - a*b
219 # a + b*(1 - a)
220 # b*(1 - a) + 1*a
221 # flrp(b, 1, a)
222 (('~fadd@32', 1.0, ('fneg', ('fmul', ('fadd', 1.0, ('fneg', a)), ('fadd', 1.0, ('fneg', b))))),
223 ('flrp', b, 1.0, a), '!options->lower_flrp32'),
224
225 # (a * #b + #c) << #d
226 # ((a * #b) << #d) + (#c << #d)
227 # (a * (#b << #d)) + (#c << #d)
228 (('ishl', ('iadd', ('imul', a, '#b'), '#c'), '#d'),
229 ('iadd', ('imul', a, ('ishl', b, d)), ('ishl', c, d))),
230
231 # (a * #b) << #c
232 # a * (#b << #c)
233 (('ishl', ('imul', a, '#b'), '#c'), ('imul', a, ('ishl', b, c))),
234 ]
235
236 # Care must be taken here. Shifts in NIR uses only the lower log2(bitsize)
237 # bits of the second source. These replacements must correctly handle the
238 # case where (b % bitsize) + (c % bitsize) >= bitsize.
239 for s in [8, 16, 32, 64]:
240 mask = (1 << s) - 1
241
242 ishl = "ishl@{}".format(s)
243 ishr = "ishr@{}".format(s)
244 ushr = "ushr@{}".format(s)
245
246 in_bounds = ('ult', ('iadd', ('iand', b, mask), ('iand', c, mask)), s)
247
248 optimizations.extend([
249 ((ishl, (ishl, a, '#b'), '#c'), ('bcsel', in_bounds, (ishl, a, ('iadd', b, c)), 0)),
250 ((ushr, (ushr, a, '#b'), '#c'), ('bcsel', in_bounds, (ushr, a, ('iadd', b, c)), 0)),
251
252 # To get get -1 for large shifts of negative values, ishr must instead
253 # clamp the shift count to the maximum value.
254 ((ishr, (ishr, a, '#b'), '#c'),
255 (ishr, a, ('imin', ('iadd', ('iand', b, mask), ('iand', c, mask)), s - 1))),
256 ])
257
258 # Optimize a pattern of address calculation created by DXVK where the offset is
259 # divided by 4 and then multipled by 4. This can be turned into an iand and the
260 # additions before can be reassociated to CSE the iand instruction.
261 for log2 in range(1, 7): # powers of two from 2 to 64
262 v = 1 << log2
263 mask = 0xffffffff & ~(v - 1)
264 b_is_multiple = '#b(is_unsigned_multiple_of_{})'.format(v)
265
266 optimizations.extend([
267 # 'a >> #b << #b' -> 'a & ~((1 << #b) - 1)'
268 (('ishl@32', ('ushr@32', a, log2), log2), ('iand', a, mask)),
269
270 # Reassociate for improved CSE
271 (('iand@32', ('iadd@32', a, b_is_multiple), mask), ('iadd', ('iand', a, mask), b)),
272 ])
273
274 optimizations.extend([
275 # This is common for address calculations. Reassociating may enable the
276 # 'a<<c' to be CSE'd. It also helps architectures that have an ISHLADD
277 # instruction or a constant offset field for in load / store instructions.
278 (('ishl', ('iadd', a, '#b'), '#c'), ('iadd', ('ishl', a, c), ('ishl', b, c))),
279
280 # Comparison simplifications
281 (('~inot', ('flt', a, b)), ('fge', a, b)),
282 (('~inot', ('fge', a, b)), ('flt', a, b)),
283 (('inot', ('feq', a, b)), ('fne', a, b)),
284 (('inot', ('fne', a, b)), ('feq', a, b)),
285 (('inot', ('ilt', a, b)), ('ige', a, b)),
286 (('inot', ('ult', a, b)), ('uge', a, b)),
287 (('inot', ('ige', a, b)), ('ilt', a, b)),
288 (('inot', ('uge', a, b)), ('ult', a, b)),
289 (('inot', ('ieq', a, b)), ('ine', a, b)),
290 (('inot', ('ine', a, b)), ('ieq', a, b)),
291
292 (('iand', ('feq', a, b), ('fne', a, b)), False),
293 (('iand', ('flt', a, b), ('flt', b, a)), False),
294 (('iand', ('ieq', a, b), ('ine', a, b)), False),
295 (('iand', ('ilt', a, b), ('ilt', b, a)), False),
296 (('iand', ('ult', a, b), ('ult', b, a)), False),
297
298 # This helps some shaders because, after some optimizations, they end up
299 # with patterns like (-a < -b) || (b < a). In an ideal world, this sort of
300 # matching would be handled by CSE.
301 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
302 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
303 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
304 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
305 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
306 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
307 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
308 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
309 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
310 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
311
312 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
313 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
314 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
315 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
316 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
317 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
318
319 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
320 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
321 (('fge', 0.0, ('fsat(is_used_once)', a)), ('fge', 0.0, a)),
322 (('flt', 0.0, ('fsat(is_used_once)', a)), ('flt', 0.0, a)),
323
324 # 0.0 >= b2f(a)
325 # b2f(a) <= 0.0
326 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
327 # inot(a)
328 (('fge', 0.0, ('b2f', 'a@1')), ('inot', a)),
329
330 (('fge', ('fneg', ('b2f', 'a@1')), 0.0), ('inot', a)),
331
332 (('fne', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
333 (('fne', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('ior', a, b)),
334 (('fne', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('ior', a, b)),
335 (('fne', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('ior', a, b)),
336 (('fne', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
337 (('fne', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('iand', a, b)),
338 (('fne', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('iand', a, b)),
339 (('fne', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ixor', a, b)),
340 (('fne', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ixor', a, b)),
341 (('fne', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ixor', a, b)),
342 (('feq', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
343 (('feq', ('fmax', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('ior', a, b))),
344 (('feq', ('bcsel', a, 1.0, ('b2f', 'b@1')) , 0.0), ('inot', ('ior', a, b))),
345 (('feq', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
346 (('feq', ('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
347 (('feq', ('fmin', ('b2f', 'a@1'), ('b2f', 'b@1')), 0.0), ('inot', ('iand', a, b))),
348 (('feq', ('bcsel', a, ('b2f', 'b@1'), 0.0) , 0.0), ('inot', ('iand', a, b))),
349 (('feq', ('fadd', ('b2f', 'a@1'), ('fneg', ('b2f', 'b@1'))), 0.0), ('ieq', a, b)),
350 (('feq', ('b2f', 'a@1') , ('b2f', 'b@1') ), ('ieq', a, b)),
351 (('feq', ('fneg', ('b2f', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('ieq', a, b)),
352
353 # -(b2f(a) + b2f(b)) < 0
354 # 0 < b2f(a) + b2f(b)
355 # 0 != b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
356 # a || b
357 (('flt', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('ior', a, b)),
358 (('flt', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('ior', a, b)),
359
360 # -(b2f(a) + b2f(b)) >= 0
361 # 0 >= b2f(a) + b2f(b)
362 # 0 == b2f(a) + b2f(b) b2f must be 0 or 1, so the sum is non-negative
363 # !(a || b)
364 (('fge', ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), 0.0), ('inot', ('ior', a, b))),
365 (('fge', 0.0, ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('inot', ('ior', a, b))),
366
367 (('flt', a, ('fneg', a)), ('flt', a, 0.0)),
368 (('fge', a, ('fneg', a)), ('fge', a, 0.0)),
369
370 # Some optimizations (below) convert things like (a < b || c < b) into
371 # (min(a, c) < b). However, this interfers with the previous optimizations
372 # that try to remove comparisons with negated sums of b2f. This just
373 # breaks that apart.
374 (('flt', ('fmin', c, ('fneg', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1')))), 0.0),
375 ('ior', ('flt', c, 0.0), ('ior', a, b))),
376
377 (('~flt', ('fadd', a, b), a), ('flt', b, 0.0)),
378 (('~fge', ('fadd', a, b), a), ('fge', b, 0.0)),
379 (('~feq', ('fadd', a, b), a), ('feq', b, 0.0)),
380 (('~fne', ('fadd', a, b), a), ('fne', b, 0.0)),
381 (('~flt', ('fadd(is_used_once)', a, '#b'), '#c'), ('flt', a, ('fadd', c, ('fneg', b)))),
382 (('~flt', ('fneg(is_used_once)', ('fadd(is_used_once)', a, '#b')), '#c'), ('flt', ('fneg', ('fadd', c, b)), a)),
383 (('~fge', ('fadd(is_used_once)', a, '#b'), '#c'), ('fge', a, ('fadd', c, ('fneg', b)))),
384 (('~fge', ('fneg(is_used_once)', ('fadd(is_used_once)', a, '#b')), '#c'), ('fge', ('fneg', ('fadd', c, b)), a)),
385 (('~feq', ('fadd(is_used_once)', a, '#b'), '#c'), ('feq', a, ('fadd', c, ('fneg', b)))),
386 (('~feq', ('fneg(is_used_once)', ('fadd(is_used_once)', a, '#b')), '#c'), ('feq', ('fneg', ('fadd', c, b)), a)),
387 (('~fne', ('fadd(is_used_once)', a, '#b'), '#c'), ('fne', a, ('fadd', c, ('fneg', b)))),
388 (('~fne', ('fneg(is_used_once)', ('fadd(is_used_once)', a, '#b')), '#c'), ('fne', ('fneg', ('fadd', c, b)), a)),
389
390 # Cannot remove the addition from ilt or ige due to overflow.
391 (('ieq', ('iadd', a, b), a), ('ieq', b, 0)),
392 (('ine', ('iadd', a, b), a), ('ine', b, 0)),
393
394 # fmin(-b2f(a), b) >= 0.0
395 # -b2f(a) >= 0.0 && b >= 0.0
396 # -b2f(a) == 0.0 && b >= 0.0 -b2f can only be 0 or -1, never >0
397 # b2f(a) == 0.0 && b >= 0.0
398 # a == False && b >= 0.0
399 # !a && b >= 0.0
400 #
401 # The fge in the second replacement is not a typo. I leave the proof that
402 # "fmin(-b2f(a), b) >= 0 <=> fmin(-b2f(a), b) == 0" as an exercise for the
403 # reader.
404 (('fge', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
405 (('feq', ('fmin', ('fneg', ('b2f', 'a@1')), 'b@1'), 0.0), ('iand', ('inot', a), ('fge', b, 0.0))),
406
407 (('feq', ('b2f', 'a@1'), 0.0), ('inot', a)),
408 (('~fne', ('b2f', 'a@1'), 0.0), a),
409 (('ieq', ('b2i', 'a@1'), 0), ('inot', a)),
410 (('ine', ('b2i', 'a@1'), 0), a),
411
412 (('fne', ('u2f', a), 0.0), ('ine', a, 0)),
413 (('feq', ('u2f', a), 0.0), ('ieq', a, 0)),
414 (('fge', ('u2f', a), 0.0), True),
415 (('fge', 0.0, ('u2f', a)), ('uge', 0, a)), # ieq instead?
416 (('flt', ('u2f', a), 0.0), False),
417 (('flt', 0.0, ('u2f', a)), ('ult', 0, a)), # ine instead?
418 (('fne', ('i2f', a), 0.0), ('ine', a, 0)),
419 (('feq', ('i2f', a), 0.0), ('ieq', a, 0)),
420 (('fge', ('i2f', a), 0.0), ('ige', a, 0)),
421 (('fge', 0.0, ('i2f', a)), ('ige', 0, a)),
422 (('flt', ('i2f', a), 0.0), ('ilt', a, 0)),
423 (('flt', 0.0, ('i2f', a)), ('ilt', 0, a)),
424
425 # 0.0 < fabs(a)
426 # fabs(a) > 0.0
427 # fabs(a) != 0.0 because fabs(a) must be >= 0
428 # a != 0.0
429 (('~flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
430
431 # -fabs(a) < 0.0
432 # fabs(a) > 0.0
433 (('~flt', ('fneg', ('fabs', a)), 0.0), ('fne', a, 0.0)),
434
435 # 0.0 >= fabs(a)
436 # 0.0 == fabs(a) because fabs(a) must be >= 0
437 # 0.0 == a
438 (('fge', 0.0, ('fabs', a)), ('feq', a, 0.0)),
439
440 # -fabs(a) >= 0.0
441 # 0.0 >= fabs(a)
442 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
443
444 # (a >= 0.0) && (a <= 1.0) -> fsat(a) == a
445 (('iand', ('fge', a, 0.0), ('fge', 1.0, a)), ('feq', a, ('fsat', a)), '!options->lower_fsat'),
446
447 # (a < 0.0) || (a > 1.0)
448 # !(!(a < 0.0) && !(a > 1.0))
449 # !((a >= 0.0) && (a <= 1.0))
450 # !(a == fsat(a))
451 # a != fsat(a)
452 (('ior', ('flt', a, 0.0), ('flt', 1.0, a)), ('fne', a, ('fsat', a)), '!options->lower_fsat'),
453
454 (('fmax', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('ior', a, b))),
455 (('fmax', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('ior', a, b)))),
456 (('fmin', ('b2f(is_used_once)', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
457 (('fmin', ('fneg(is_used_once)', ('b2f(is_used_once)', 'a@1')), ('fneg', ('b2f', 'b@1'))), ('fneg', ('b2f', ('iand', a, b)))),
458
459 # fmin(b2f(a), b)
460 # bcsel(a, fmin(b2f(a), b), fmin(b2f(a), b))
461 # bcsel(a, fmin(b2f(True), b), fmin(b2f(False), b))
462 # bcsel(a, fmin(1.0, b), fmin(0.0, b))
463 #
464 # Since b is a constant, constant folding will eliminate the fmin and the
465 # fmax. If b is > 1.0, the bcsel will be replaced with a b2f.
466 (('fmin', ('b2f', 'a@1'), '#b'), ('bcsel', a, ('fmin', b, 1.0), ('fmin', b, 0.0))),
467
468 (('flt', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)),
469
470 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
471 (('~bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
472 (('~bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
473 (('~bcsel', ('fge', a, b), b, a), ('fmin', a, b)),
474 (('~bcsel', ('fge', b, a), b, a), ('fmax', a, b)),
475 (('bcsel', ('i2b', a), b, c), ('bcsel', ('ine', a, 0), b, c)),
476 (('bcsel', ('inot', a), b, c), ('bcsel', a, c, b)),
477 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
478 (('bcsel', a, b, ('bcsel', a, c, d)), ('bcsel', a, b, d)),
479 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
480 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, c, 'e')), ('bcsel', b, c, ('bcsel', a, d, 'e'))),
481 (('bcsel', a, ('bcsel', b, c, d), ('bcsel(is_used_once)', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
482 (('bcsel', a, ('bcsel(is_used_once)', b, c, d), ('bcsel', b, 'e', d)), ('bcsel', b, ('bcsel', a, c, 'e'), d)),
483 (('bcsel', a, True, b), ('ior', a, b)),
484 (('bcsel', a, a, b), ('ior', a, b)),
485 (('bcsel', a, b, False), ('iand', a, b)),
486 (('bcsel', a, b, a), ('iand', a, b)),
487 (('~fmin', a, a), a),
488 (('~fmax', a, a), a),
489 (('imin', a, a), a),
490 (('imax', a, a), a),
491 (('umin', a, a), a),
492 (('umax', a, a), a),
493 (('fmax', ('fmax', a, b), b), ('fmax', a, b)),
494 (('umax', ('umax', a, b), b), ('umax', a, b)),
495 (('imax', ('imax', a, b), b), ('imax', a, b)),
496 (('fmin', ('fmin', a, b), b), ('fmin', a, b)),
497 (('umin', ('umin', a, b), b), ('umin', a, b)),
498 (('imin', ('imin', a, b), b), ('imin', a, b)),
499 (('iand@32', a, ('inot', ('ishr', a, 31))), ('imax', a, 0)),
500 (('fmin', a, ('fneg', a)), ('fneg', ('fabs', a))),
501 (('imin', a, ('ineg', a)), ('ineg', ('iabs', a))),
502 (('fmin', a, ('fneg', ('fabs', a))), ('fneg', ('fabs', a))),
503 (('imin', a, ('ineg', ('iabs', a))), ('ineg', ('iabs', a))),
504 (('~fmin', a, ('fabs', a)), a),
505 (('imin', a, ('iabs', a)), a),
506 (('~fmax', a, ('fneg', ('fabs', a))), a),
507 (('imax', a, ('ineg', ('iabs', a))), a),
508 (('fmax', a, ('fabs', a)), ('fabs', a)),
509 (('imax', a, ('iabs', a)), ('iabs', a)),
510 (('fmax', a, ('fneg', a)), ('fabs', a)),
511 (('imax', a, ('ineg', a)), ('iabs', a)),
512 (('~fmax', ('fabs', a), 0.0), ('fabs', a)),
513 (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
514 (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
515 (('~fmin', ('fmax', a, -1.0), 0.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_fsat'),
516 (('~fmax', ('fmin', a, 0.0), -1.0), ('fneg', ('fsat', ('fneg', a))), '!options->lower_fsat'),
517 (('fsat', ('fsign', a)), ('b2f', ('flt', 0.0, a))),
518 (('fsat', ('b2f', a)), ('b2f', a)),
519 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
520 (('fsat', ('fsat', a)), ('fsat', a)),
521 (('fsat', ('fneg(is_used_once)', ('fadd(is_used_once)', a, b))), ('fsat', ('fadd', ('fneg', a), ('fneg', b))), '!options->lower_fsat'),
522 (('fsat', ('fneg(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fneg', a), b)), '!options->lower_fsat'),
523 (('fsat', ('fabs(is_used_once)', ('fmul(is_used_once)', a, b))), ('fsat', ('fmul', ('fabs', a), ('fabs', b))), '!options->lower_fsat'),
524 (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
525 (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
526 (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
527 (('fmax', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a, b))),
528 (('fmin', ('fsat', a), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a, b))),
529 (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
530 (('~ior', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
531 (('~ior', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
532 (('~ior', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
533 (('~ior', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
534 (('~ior', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmax', b, c))),
535 (('~ior', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmin', a, b), c)),
536 (('~ior', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmin', b, c))),
537 (('~ior', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmax', a, b), c)),
538 (('~iand', ('flt(is_used_once)', a, b), ('flt', a, c)), ('flt', a, ('fmin', b, c))),
539 (('~iand', ('flt(is_used_once)', a, c), ('flt', b, c)), ('flt', ('fmax', a, b), c)),
540 (('~iand', ('fge(is_used_once)', a, b), ('fge', a, c)), ('fge', a, ('fmax', b, c))),
541 (('~iand', ('fge(is_used_once)', a, c), ('fge', b, c)), ('fge', ('fmin', a, b), c)),
542 (('~iand', ('flt', a, '#b'), ('flt', a, '#c')), ('flt', a, ('fmin', b, c))),
543 (('~iand', ('flt', '#a', c), ('flt', '#b', c)), ('flt', ('fmax', a, b), c)),
544 (('~iand', ('fge', a, '#b'), ('fge', a, '#c')), ('fge', a, ('fmax', b, c))),
545 (('~iand', ('fge', '#a', c), ('fge', '#b', c)), ('fge', ('fmin', a, b), c)),
546
547 (('ior', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imax', b, c))),
548 (('ior', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imin', a, b), c)),
549 (('ior', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imin', b, c))),
550 (('ior', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imax', a, b), c)),
551 (('ior', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umax', b, c))),
552 (('ior', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umin', a, b), c)),
553 (('ior', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umin', b, c))),
554 (('ior', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umax', a, b), c)),
555 (('iand', ('ilt(is_used_once)', a, b), ('ilt', a, c)), ('ilt', a, ('imin', b, c))),
556 (('iand', ('ilt(is_used_once)', a, c), ('ilt', b, c)), ('ilt', ('imax', a, b), c)),
557 (('iand', ('ige(is_used_once)', a, b), ('ige', a, c)), ('ige', a, ('imax', b, c))),
558 (('iand', ('ige(is_used_once)', a, c), ('ige', b, c)), ('ige', ('imin', a, b), c)),
559 (('iand', ('ult(is_used_once)', a, b), ('ult', a, c)), ('ult', a, ('umin', b, c))),
560 (('iand', ('ult(is_used_once)', a, c), ('ult', b, c)), ('ult', ('umax', a, b), c)),
561 (('iand', ('uge(is_used_once)', a, b), ('uge', a, c)), ('uge', a, ('umax', b, c))),
562 (('iand', ('uge(is_used_once)', a, c), ('uge', b, c)), ('uge', ('umin', a, b), c)),
563
564 # These derive from the previous patterns with the application of b < 0 <=>
565 # 0 < -b. The transformation should be applied if either comparison is
566 # used once as this ensures that the number of comparisons will not
567 # increase. The sources to the ior and iand are not symmetric, so the
568 # rules have to be duplicated to get this behavior.
569 (('~ior', ('flt(is_used_once)', 0.0, 'a@32'), ('flt', 'b@32', 0.0)), ('flt', 0.0, ('fmax', a, ('fneg', b)))),
570 (('~ior', ('flt', 0.0, 'a@32'), ('flt(is_used_once)', 'b@32', 0.0)), ('flt', 0.0, ('fmax', a, ('fneg', b)))),
571 (('~ior', ('fge(is_used_once)', 0.0, 'a@32'), ('fge', 'b@32', 0.0)), ('fge', 0.0, ('fmin', a, ('fneg', b)))),
572 (('~ior', ('fge', 0.0, 'a@32'), ('fge(is_used_once)', 'b@32', 0.0)), ('fge', 0.0, ('fmin', a, ('fneg', b)))),
573 (('~iand', ('flt(is_used_once)', 0.0, 'a@32'), ('flt', 'b@32', 0.0)), ('flt', 0.0, ('fmin', a, ('fneg', b)))),
574 (('~iand', ('flt', 0.0, 'a@32'), ('flt(is_used_once)', 'b@32', 0.0)), ('flt', 0.0, ('fmin', a, ('fneg', b)))),
575 (('~iand', ('fge(is_used_once)', 0.0, 'a@32'), ('fge', 'b@32', 0.0)), ('fge', 0.0, ('fmax', a, ('fneg', b)))),
576 (('~iand', ('fge', 0.0, 'a@32'), ('fge(is_used_once)', 'b@32', 0.0)), ('fge', 0.0, ('fmax', a, ('fneg', b)))),
577
578 # Common pattern like 'if (i == 0 || i == 1 || ...)'
579 (('ior', ('ieq', a, 0), ('ieq', a, 1)), ('uge', 1, a)),
580 (('ior', ('uge', 1, a), ('ieq', a, 2)), ('uge', 2, a)),
581 (('ior', ('uge', 2, a), ('ieq', a, 3)), ('uge', 3, a)),
582
583 # The (i2f32, ...) part is an open-coded fsign. When that is combined with
584 # the bcsel, it's basically copysign(1.0, a). There is no copysign in NIR,
585 # so emit an open-coded version of that.
586 (('bcsel@32', ('feq', a, 0.0), 1.0, ('i2f32', ('iadd', ('b2i32', ('flt', 0.0, 'a@32')), ('ineg', ('b2i32', ('flt', 'a@32', 0.0)))))),
587 ('ior', 0x3f800000, ('iand', a, 0x80000000))),
588
589 (('ior', a, ('ieq', a, False)), True),
590 (('ior', a, ('inot', a)), -1),
591
592 (('ine', ('ineg', ('b2i32', 'a@1')), ('ineg', ('b2i32', 'b@1'))), ('ine', a, b)),
593 (('b2i32', ('ine', 'a@1', 'b@1')), ('b2i32', ('ixor', a, b))),
594
595 (('iand', ('ieq', 'a@32', 0), ('ieq', 'b@32', 0)), ('ieq', ('ior', 'a@32', 'b@32'), 0), '!options->lower_bitops'),
596
597 # These patterns can result when (a < b || a < c) => (a < min(b, c))
598 # transformations occur before constant propagation and loop-unrolling.
599 (('~flt', a, ('fmax', b, a)), ('flt', a, b)),
600 (('~flt', ('fmin', a, b), a), ('flt', b, a)),
601 (('~fge', a, ('fmin', b, a)), True),
602 (('~fge', ('fmax', a, b), a), True),
603 (('~flt', a, ('fmin', b, a)), False),
604 (('~flt', ('fmax', a, b), a), False),
605 (('~fge', a, ('fmax', b, a)), ('fge', a, b)),
606 (('~fge', ('fmin', a, b), a), ('fge', b, a)),
607
608 (('ilt', a, ('imax', b, a)), ('ilt', a, b)),
609 (('ilt', ('imin', a, b), a), ('ilt', b, a)),
610 (('ige', a, ('imin', b, a)), True),
611 (('ige', ('imax', a, b), a), True),
612 (('ult', a, ('umax', b, a)), ('ult', a, b)),
613 (('ult', ('umin', a, b), a), ('ult', b, a)),
614 (('uge', a, ('umin', b, a)), True),
615 (('uge', ('umax', a, b), a), True),
616 (('ilt', a, ('imin', b, a)), False),
617 (('ilt', ('imax', a, b), a), False),
618 (('ige', a, ('imax', b, a)), ('ige', a, b)),
619 (('ige', ('imin', a, b), a), ('ige', b, a)),
620 (('ult', a, ('umin', b, a)), False),
621 (('ult', ('umax', a, b), a), False),
622 (('uge', a, ('umax', b, a)), ('uge', a, b)),
623 (('uge', ('umin', a, b), a), ('uge', b, a)),
624 (('ult', a, ('iand', b, a)), False),
625 (('ult', ('ior', a, b), a), False),
626 (('uge', a, ('iand', b, a)), True),
627 (('uge', ('ior', a, b), a), True),
628
629 (('ilt', '#a', ('imax', '#b', c)), ('ior', ('ilt', a, b), ('ilt', a, c))),
630 (('ilt', ('imin', '#a', b), '#c'), ('ior', ('ilt', a, c), ('ilt', b, c))),
631 (('ige', '#a', ('imin', '#b', c)), ('ior', ('ige', a, b), ('ige', a, c))),
632 (('ige', ('imax', '#a', b), '#c'), ('ior', ('ige', a, c), ('ige', b, c))),
633 (('ult', '#a', ('umax', '#b', c)), ('ior', ('ult', a, b), ('ult', a, c))),
634 (('ult', ('umin', '#a', b), '#c'), ('ior', ('ult', a, c), ('ult', b, c))),
635 (('uge', '#a', ('umin', '#b', c)), ('ior', ('uge', a, b), ('uge', a, c))),
636 (('uge', ('umax', '#a', b), '#c'), ('ior', ('uge', a, c), ('uge', b, c))),
637 (('ilt', '#a', ('imin', '#b', c)), ('iand', ('ilt', a, b), ('ilt', a, c))),
638 (('ilt', ('imax', '#a', b), '#c'), ('iand', ('ilt', a, c), ('ilt', b, c))),
639 (('ige', '#a', ('imax', '#b', c)), ('iand', ('ige', a, b), ('ige', a, c))),
640 (('ige', ('imin', '#a', b), '#c'), ('iand', ('ige', a, c), ('ige', b, c))),
641 (('ult', '#a', ('umin', '#b', c)), ('iand', ('ult', a, b), ('ult', a, c))),
642 (('ult', ('umax', '#a', b), '#c'), ('iand', ('ult', a, c), ('ult', b, c))),
643 (('uge', '#a', ('umax', '#b', c)), ('iand', ('uge', a, b), ('uge', a, c))),
644 (('uge', ('umin', '#a', b), '#c'), ('iand', ('uge', a, c), ('uge', b, c))),
645
646 # Thanks to sign extension, the ishr(a, b) is negative if and only if a is
647 # negative.
648 (('bcsel', ('ilt', a, 0), ('ineg', ('ishr', a, b)), ('ishr', a, b)),
649 ('iabs', ('ishr', a, b))),
650 (('iabs', ('ishr', ('iabs', a), b)), ('ishr', ('iabs', a), b)),
651
652 (('fabs', ('slt', a, b)), ('slt', a, b)),
653 (('fabs', ('sge', a, b)), ('sge', a, b)),
654 (('fabs', ('seq', a, b)), ('seq', a, b)),
655 (('fabs', ('sne', a, b)), ('sne', a, b)),
656 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
657 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
658 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
659 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
660 (('seq', ('seq', a, b), 1.0), ('seq', a, b)),
661 (('seq', ('sne', a, b), 1.0), ('sne', a, b)),
662 (('seq', ('slt', a, b), 1.0), ('slt', a, b)),
663 (('seq', ('sge', a, b), 1.0), ('sge', a, b)),
664 (('sne', ('seq', a, b), 0.0), ('seq', a, b)),
665 (('sne', ('sne', a, b), 0.0), ('sne', a, b)),
666 (('sne', ('slt', a, b), 0.0), ('slt', a, b)),
667 (('sne', ('sge', a, b), 0.0), ('sge', a, b)),
668 (('seq', ('seq', a, b), 0.0), ('sne', a, b)),
669 (('seq', ('sne', a, b), 0.0), ('seq', a, b)),
670 (('seq', ('slt', a, b), 0.0), ('sge', a, b)),
671 (('seq', ('sge', a, b), 0.0), ('slt', a, b)),
672 (('sne', ('seq', a, b), 1.0), ('sne', a, b)),
673 (('sne', ('sne', a, b), 1.0), ('seq', a, b)),
674 (('sne', ('slt', a, b), 1.0), ('sge', a, b)),
675 (('sne', ('sge', a, b), 1.0), ('slt', a, b)),
676 (('fall_equal2', a, b), ('fmin', ('seq', 'a.x', 'b.x'), ('seq', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
677 (('fall_equal3', a, b), ('seq', ('fany_nequal3', a, b), 0.0), 'options->lower_vector_cmp'),
678 (('fall_equal4', a, b), ('seq', ('fany_nequal4', a, b), 0.0), 'options->lower_vector_cmp'),
679 (('fany_nequal2', a, b), ('fmax', ('sne', 'a.x', 'b.x'), ('sne', 'a.y', 'b.y')), 'options->lower_vector_cmp'),
680 (('fany_nequal3', a, b), ('fsat', ('fdot3', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
681 (('fany_nequal4', a, b), ('fsat', ('fdot4', ('sne', a, b), ('sne', a, b))), 'options->lower_vector_cmp'),
682 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
683 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
684 # Emulating booleans
685 (('imul', ('b2i', 'a@1'), ('b2i', 'b@1')), ('b2i', ('iand', a, b))),
686 (('fmul', ('b2f', 'a@1'), ('b2f', 'b@1')), ('b2f', ('iand', a, b))),
687 (('fsat', ('fadd', ('b2f', 'a@1'), ('b2f', 'b@1'))), ('b2f', ('ior', a, b))),
688 (('iand', 'a@bool32', 1.0), ('b2f', a)),
689 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
690 (('ineg', ('b2i32', 'a@32')), a),
691 (('flt', ('fneg', ('b2f', 'a@1')), 0), a), # Generated by TGSI KILL_IF.
692 # Comparison with the same args. Note that these are not done for
693 # the float versions because NaN always returns false on float
694 # inequalities.
695 (('ilt', a, a), False),
696 (('ige', a, a), True),
697 (('ieq', a, a), True),
698 (('ine', a, a), False),
699 (('ult', a, a), False),
700 (('uge', a, a), True),
701 # Logical and bit operations
702 (('iand', a, a), a),
703 (('iand', a, ~0), a),
704 (('iand', a, 0), 0),
705 (('ior', a, a), a),
706 (('ior', a, 0), a),
707 (('ior', a, True), True),
708 (('ixor', a, a), 0),
709 (('ixor', a, 0), a),
710 (('inot', ('inot', a)), a),
711 (('ior', ('iand', a, b), b), b),
712 (('ior', ('ior', a, b), b), ('ior', a, b)),
713 (('iand', ('ior', a, b), b), b),
714 (('iand', ('iand', a, b), b), ('iand', a, b)),
715 # DeMorgan's Laws
716 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
717 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
718 # Shift optimizations
719 (('ishl', 0, a), 0),
720 (('ishl', a, 0), a),
721 (('ishr', 0, a), 0),
722 (('ishr', a, 0), a),
723 (('ushr', 0, a), 0),
724 (('ushr', a, 0), a),
725 (('iand', 0xff, ('ushr@32', a, 24)), ('ushr', a, 24)),
726 (('iand', 0xffff, ('ushr@32', a, 16)), ('ushr', a, 16)),
727 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('iadd', 16, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
728 (('ior', ('ishl@16', a, b), ('ushr@16', a, ('isub', 16, b))), ('urol', a, b), '!options->lower_rotate'),
729 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('iadd', 32, ('ineg', b)))), ('urol', a, b), '!options->lower_rotate'),
730 (('ior', ('ishl@32', a, b), ('ushr@32', a, ('isub', 32, b))), ('urol', a, b), '!options->lower_rotate'),
731 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('iadd', 16, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
732 (('ior', ('ushr@16', a, b), ('ishl@16', a, ('isub', 16, b))), ('uror', a, b), '!options->lower_rotate'),
733 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('iadd', 32, ('ineg', b)))), ('uror', a, b), '!options->lower_rotate'),
734 (('ior', ('ushr@32', a, b), ('ishl@32', a, ('isub', 32, b))), ('uror', a, b), '!options->lower_rotate'),
735 (('urol@16', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 16, b))), 'options->lower_rotate'),
736 (('urol@32', a, b), ('ior', ('ishl', a, b), ('ushr', a, ('isub', 32, b))), 'options->lower_rotate'),
737 (('uror@16', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 16, b))), 'options->lower_rotate'),
738 (('uror@32', a, b), ('ior', ('ushr', a, b), ('ishl', a, ('isub', 32, b))), 'options->lower_rotate'),
739 # Exponential/logarithmic identities
740 (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
741 (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
742 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
743 (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
744 (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
745 ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
746 (('~fexp2', ('fmul', ('flog2', a), 2.0)), ('fmul', a, a)),
747 (('~fexp2', ('fmul', ('flog2', a), 4.0)), ('fmul', ('fmul', a, a), ('fmul', a, a))),
748 (('~fpow', a, 1.0), a),
749 (('~fpow', a, 2.0), ('fmul', a, a)),
750 (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
751 (('~fpow', 2.0, a), ('fexp2', a)),
752 (('~fpow', ('fpow', a, 2.2), 0.454545), a),
753 (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
754 (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
755 (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
756 (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
757 (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
758 (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
759 (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
760 (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
761 (('~fmul', ('fexp2(is_used_once)', a), ('fexp2(is_used_once)', b)), ('fexp2', ('fadd', a, b))),
762 (('bcsel', ('flt', a, 0.0), 0.0, ('fsqrt', a)), ('fsqrt', ('fmax', a, 0.0))),
763 (('~fmul', ('fsqrt', a), ('fsqrt', a)), ('fabs',a)),
764 # Division and reciprocal
765 (('~fdiv', 1.0, a), ('frcp', a)),
766 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
767 (('~frcp', ('frcp', a)), a),
768 (('~frcp', ('fsqrt', a)), ('frsq', a)),
769 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
770 (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
771 # Trig
772 (('fsin', a), lowered_sincos(0.5), 'options->lower_sincos'),
773 (('fcos', a), lowered_sincos(0.75), 'options->lower_sincos'),
774 # Boolean simplifications
775 (('i2b32(is_used_by_if)', a), ('ine32', a, 0)),
776 (('i2b1(is_used_by_if)', a), ('ine', a, 0)),
777 (('ieq', a, True), a),
778 (('ine(is_not_used_by_if)', a, True), ('inot', a)),
779 (('ine', a, False), a),
780 (('ieq(is_not_used_by_if)', a, False), ('inot', 'a')),
781 (('bcsel', a, True, False), a),
782 (('bcsel', a, False, True), ('inot', a)),
783 (('bcsel@32', a, 1.0, 0.0), ('b2f', a)),
784 (('bcsel@32', a, 0.0, 1.0), ('b2f', ('inot', a))),
785 (('bcsel@32', a, -1.0, -0.0), ('fneg', ('b2f', a))),
786 (('bcsel@32', a, -0.0, -1.0), ('fneg', ('b2f', ('inot', a)))),
787 (('bcsel', True, b, c), b),
788 (('bcsel', False, b, c), c),
789 (('bcsel', a, ('b2f(is_used_once)', 'b@32'), ('b2f', 'c@32')), ('b2f', ('bcsel', a, b, c))),
790
791 (('bcsel', a, b, b), b),
792 (('~fcsel', a, b, b), b),
793
794 # D3D Boolean emulation
795 (('bcsel', a, -1, 0), ('ineg', ('b2i', 'a@1'))),
796 (('bcsel', a, 0, -1), ('ineg', ('b2i', ('inot', a)))),
797 (('iand', ('ineg', ('b2i', 'a@1')), ('ineg', ('b2i', 'b@1'))),
798 ('ineg', ('b2i', ('iand', a, b)))),
799 (('ior', ('ineg', ('b2i','a@1')), ('ineg', ('b2i', 'b@1'))),
800 ('ineg', ('b2i', ('ior', a, b)))),
801 (('ieq', ('ineg', ('b2i', 'a@1')), 0), ('inot', a)),
802 (('ieq', ('ineg', ('b2i', 'a@1')), -1), a),
803 (('ine', ('ineg', ('b2i', 'a@1')), 0), a),
804 (('ine', ('ineg', ('b2i', 'a@1')), -1), ('inot', a)),
805 (('iand', ('ineg', ('b2i', a)), 1.0), ('b2f', a)),
806 (('iand', ('ineg', ('b2i', a)), 1), ('b2i', a)),
807
808 # SM5 32-bit shifts are defined to use the 5 least significant bits
809 (('ishl', 'a@32', ('iand', 31, b)), ('ishl', a, b)),
810 (('ishr', 'a@32', ('iand', 31, b)), ('ishr', a, b)),
811 (('ushr', 'a@32', ('iand', 31, b)), ('ushr', a, b)),
812
813 # Conversions
814 (('i2b32', ('b2i', 'a@32')), a),
815 (('f2i', ('ftrunc', a)), ('f2i', a)),
816 (('f2u', ('ftrunc', a)), ('f2u', a)),
817 (('i2b', ('ineg', a)), ('i2b', a)),
818 (('i2b', ('iabs', a)), ('i2b', a)),
819 (('inot', ('f2b1', a)), ('feq', a, 0.0)),
820
821 # The C spec says, "If the value of the integral part cannot be represented
822 # by the integer type, the behavior is undefined." "Undefined" can mean
823 # "the conversion doesn't happen at all."
824 (('~i2f32', ('f2i32', 'a@32')), ('ftrunc', a)),
825
826 # Ironically, mark these as imprecise because removing the conversions may
827 # preserve more precision than doing the conversions (e.g.,
828 # uint(float(0x81818181u)) == 0x81818200).
829 (('~f2i32', ('i2f', 'a@32')), a),
830 (('~f2i32', ('u2f', 'a@32')), a),
831 (('~f2u32', ('i2f', 'a@32')), a),
832 (('~f2u32', ('u2f', 'a@32')), a),
833
834 # Conversions from float16 to float32 and back can always be removed
835 (('f2f16', ('f2f32', 'a@16')), a),
836 (('f2fmp', ('f2f32', 'a@16')), a),
837 # Conversions to float16 would be lossy so they should only be removed if
838 # the instruction was generated by the precision lowering pass.
839 (('f2f32', ('f2fmp', 'a@32')), a),
840
841 (('ffloor', 'a(is_integral)'), a),
842 (('fceil', 'a(is_integral)'), a),
843 (('ftrunc', 'a(is_integral)'), a),
844 # fract(x) = x - floor(x), so fract(NaN) = NaN
845 (('~ffract', 'a(is_integral)'), 0.0),
846 (('fabs', 'a(is_not_negative)'), a),
847 (('iabs', 'a(is_not_negative)'), a),
848 (('fsat', 'a(is_not_positive)'), 0.0),
849
850 # Section 5.4.1 (Conversion and Scalar Constructors) of the GLSL 4.60 spec
851 # says:
852 #
853 # It is undefined to convert a negative floating-point value to an
854 # uint.
855 #
856 # Assuming that (uint)some_float behaves like (uint)(int)some_float allows
857 # some optimizations in the i965 backend to proceed.
858 (('ige', ('f2u', a), b), ('ige', ('f2i', a), b)),
859 (('ige', b, ('f2u', a)), ('ige', b, ('f2i', a))),
860 (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
861 (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
862
863 (('~fmin', 'a(is_not_negative)', 1.0), ('fsat', a), '!options->lower_fsat'),
864
865 # The result of the multiply must be in [-1, 0], so the result of the ffma
866 # must be in [0, 1].
867 (('flt', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), False),
868 (('flt', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), False),
869 (('fmax', ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0), 0.0), ('fadd', ('fmul', ('fsat', a), ('fneg', ('fsat', a))), 1.0)),
870 (('fmax', ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0), 0.0), ('fadd', ('fneg', ('fmul', ('fsat', a), ('fsat', a))), 1.0)),
871
872 (('fne', 'a(is_not_zero)', 0.0), True),
873 (('feq', 'a(is_not_zero)', 0.0), False),
874
875 # In this chart, + means value > 0 and - means value < 0.
876 #
877 # + >= + -> unknown 0 >= + -> false - >= + -> false
878 # + >= 0 -> true 0 >= 0 -> true - >= 0 -> false
879 # + >= - -> true 0 >= - -> true - >= - -> unknown
880 #
881 # Using grouping conceptually similar to a Karnaugh map...
882 #
883 # (+ >= 0, + >= -, 0 >= 0, 0 >= -) == (is_not_negative >= is_not_positive) -> true
884 # (0 >= +, - >= +) == (is_not_positive >= gt_zero) -> false
885 # (- >= +, - >= 0) == (lt_zero >= is_not_negative) -> false
886 #
887 # The flt / ilt cases just invert the expected result.
888 #
889 # The results expecting true, must be marked imprecise. The results
890 # expecting false are fine because NaN compared >= or < anything is false.
891
892 (('~fge', 'a(is_not_negative)', 'b(is_not_positive)'), True),
893 (('fge', 'a(is_not_positive)', 'b(is_gt_zero)'), False),
894 (('fge', 'a(is_lt_zero)', 'b(is_not_negative)'), False),
895
896 (('flt', 'a(is_not_negative)', 'b(is_not_positive)'), False),
897 (('~flt', 'a(is_not_positive)', 'b(is_gt_zero)'), True),
898 (('~flt', 'a(is_lt_zero)', 'b(is_not_negative)'), True),
899
900 (('ine', 'a(is_not_zero)', 0), True),
901 (('ieq', 'a(is_not_zero)', 0), False),
902
903 (('ige', 'a(is_not_negative)', 'b(is_not_positive)'), True),
904 (('ige', 'a(is_not_positive)', 'b(is_gt_zero)'), False),
905 (('ige', 'a(is_lt_zero)', 'b(is_not_negative)'), False),
906
907 (('ilt', 'a(is_not_negative)', 'b(is_not_positive)'), False),
908 (('ilt', 'a(is_not_positive)', 'b(is_gt_zero)'), True),
909 (('ilt', 'a(is_lt_zero)', 'b(is_not_negative)'), True),
910
911 (('ult', 0, 'a(is_gt_zero)'), True),
912
913 # Packing and then unpacking does nothing
914 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a, b)), a),
915 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a, b)), b),
916 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a),
917 ('unpack_64_2x32_split_y', a)), a),
918
919 # Comparing two halves of an unpack separately. While this optimization
920 # should be correct for non-constant values, it's less obvious that it's
921 # useful in that case. For constant values, the pack will fold and we're
922 # guaranteed to reduce the whole tree to one instruction.
923 (('iand', ('ieq', ('unpack_32_2x16_split_x', a), '#b'),
924 ('ieq', ('unpack_32_2x16_split_y', a), '#c')),
925 ('ieq', a, ('pack_32_2x16_split', b, c))),
926
927 # Byte extraction
928 (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'),
929 (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
930 (('ushr', 'a@64', 56), ('extract_u8', a, 7), '!options->lower_extract_byte'),
931 (('ishr', 'a@16', 8), ('extract_i8', a, 1), '!options->lower_extract_byte'),
932 (('ishr', 'a@32', 24), ('extract_i8', a, 3), '!options->lower_extract_byte'),
933 (('ishr', 'a@64', 56), ('extract_i8', a, 7), '!options->lower_extract_byte'),
934 (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte'),
935
936 # Useless masking before unpacking
937 (('unpack_half_2x16_split_x', ('iand', a, 0xffff)), ('unpack_half_2x16_split_x', a)),
938 (('unpack_32_2x16_split_x', ('iand', a, 0xffff)), ('unpack_32_2x16_split_x', a)),
939 (('unpack_64_2x32_split_x', ('iand', a, 0xffffffff)), ('unpack_64_2x32_split_x', a)),
940 (('unpack_half_2x16_split_y', ('iand', a, 0xffff0000)), ('unpack_half_2x16_split_y', a)),
941 (('unpack_32_2x16_split_y', ('iand', a, 0xffff0000)), ('unpack_32_2x16_split_y', a)),
942 (('unpack_64_2x32_split_y', ('iand', a, 0xffffffff00000000)), ('unpack_64_2x32_split_y', a)),
943
944 # Optimize half packing
945 (('ishl', ('pack_half_2x16', ('vec2', a, 0)), 16), ('pack_half_2x16', ('vec2', 0, a))),
946 (('ishr', ('pack_half_2x16', ('vec2', 0, a)), 16), ('pack_half_2x16', ('vec2', a, 0))),
947
948 (('iadd', ('pack_half_2x16', ('vec2', a, 0)), ('pack_half_2x16', ('vec2', 0, b))),
949 ('pack_half_2x16', ('vec2', a, b))),
950 (('ior', ('pack_half_2x16', ('vec2', a, 0)), ('pack_half_2x16', ('vec2', 0, b))),
951 ('pack_half_2x16', ('vec2', a, b))),
952 ])
953
954 # After the ('extract_u8', a, 0) pattern, above, triggers, there will be
955 # patterns like those below.
956 for op in ('ushr', 'ishr'):
957 optimizations.extend([(('extract_u8', (op, 'a@16', 8), 0), ('extract_u8', a, 1))])
958 optimizations.extend([(('extract_u8', (op, 'a@32', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 4)])
959 optimizations.extend([(('extract_u8', (op, 'a@64', 8 * i), 0), ('extract_u8', a, i)) for i in range(1, 8)])
960
961 optimizations.extend([(('extract_u8', ('extract_u16', a, 1), 0), ('extract_u8', a, 2))])
962
963 # After the ('extract_[iu]8', a, 3) patterns, above, trigger, there will be
964 # patterns like those below.
965 for op in ('extract_u8', 'extract_i8'):
966 optimizations.extend([((op, ('ishl', 'a@16', 8), 1), (op, a, 0))])
967 optimizations.extend([((op, ('ishl', 'a@32', 24 - 8 * i), 3), (op, a, i)) for i in range(2, -1, -1)])
968 optimizations.extend([((op, ('ishl', 'a@64', 56 - 8 * i), 7), (op, a, i)) for i in range(6, -1, -1)])
969
970 optimizations.extend([
971 # Word extraction
972 (('ushr', ('ishl', 'a@32', 16), 16), ('extract_u16', a, 0), '!options->lower_extract_word'),
973 (('ushr', 'a@32', 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
974 (('ishr', ('ishl', 'a@32', 16), 16), ('extract_i16', a, 0), '!options->lower_extract_word'),
975 (('ishr', 'a@32', 16), ('extract_i16', a, 1), '!options->lower_extract_word'),
976 (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
977
978 # Subtracts
979 (('ussub_4x8', a, 0), a),
980 (('ussub_4x8', a, ~0), 0),
981 # Lower all Subtractions first - they can get recombined later
982 (('fsub', a, b), ('fadd', a, ('fneg', b))),
983 (('isub', a, b), ('iadd', a, ('ineg', b))),
984 (('uabs_usub', a, b), ('bcsel', ('ult', a, b), ('ineg', ('isub', a, b)), ('isub', a, b))),
985 # This is correct. We don't need isub_sat because the result type is unsigned, so it cannot overflow.
986 (('uabs_isub', a, b), ('bcsel', ('ilt', a, b), ('ineg', ('isub', a, b)), ('isub', a, b))),
987
988 # Propagate negation up multiplication chains
989 (('fmul(is_used_by_non_fsat)', ('fneg', a), b), ('fneg', ('fmul', a, b))),
990 (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
991
992 # Propagate constants up multiplication chains
993 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a, c), b)),
994 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a, c), b)),
995 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a, c), b)),
996 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a, c), b)),
997
998 # Reassociate constants in add/mul chains so they can be folded together.
999 # For now, we mostly only handle cases where the constants are separated by
1000 # a single non-constant. We could do better eventually.
1001 (('~fmul', '#a', ('fmul', 'b(is_not_const)', '#c')), ('fmul', ('fmul', a, c), b)),
1002 (('imul', '#a', ('imul', 'b(is_not_const)', '#c')), ('imul', ('imul', a, c), b)),
1003 (('~fadd', '#a', ('fadd', 'b(is_not_const)', '#c')), ('fadd', ('fadd', a, c), b)),
1004 (('~fadd', '#a', ('fneg', ('fadd', 'b(is_not_const)', '#c'))), ('fadd', ('fadd', a, ('fneg', c)), ('fneg', b))),
1005 (('iadd', '#a', ('iadd', 'b(is_not_const)', '#c')), ('iadd', ('iadd', a, c), b)),
1006
1007 # Drop mul-div by the same value when there's no wrapping.
1008 (('idiv', ('imul(no_signed_wrap)', a, b), b), a),
1009
1010 # By definition...
1011 (('bcsel', ('ige', ('find_lsb', a), 0), ('find_lsb', a), -1), ('find_lsb', a)),
1012 (('bcsel', ('ige', ('ifind_msb', a), 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
1013 (('bcsel', ('ige', ('ufind_msb', a), 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
1014
1015 (('bcsel', ('ine', a, 0), ('find_lsb', a), -1), ('find_lsb', a)),
1016 (('bcsel', ('ine', a, 0), ('ifind_msb', a), -1), ('ifind_msb', a)),
1017 (('bcsel', ('ine', a, 0), ('ufind_msb', a), -1), ('ufind_msb', a)),
1018
1019 (('bcsel', ('ine', a, -1), ('ifind_msb', a), -1), ('ifind_msb', a)),
1020
1021 # Misc. lowering
1022 (('fmod@16', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
1023 (('fmod@32', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
1024 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
1025 (('uadd_carry@32', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
1026 (('usub_borrow@32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
1027
1028 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
1029 ('bcsel', ('ult', 31, 'bits'), 'insert',
1030 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
1031 'options->lower_bitfield_insert'),
1032 (('ihadd', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
1033 (('uhadd', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
1034 (('irhadd', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd'),
1035 (('urhadd', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd'),
1036 (('ihadd@64', a, b), ('iadd', ('iand', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd64 || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1037 (('uhadd@64', a, b), ('iadd', ('iand', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd64 || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1038 (('irhadd@64', a, b), ('isub', ('ior', a, b), ('ishr', ('ixor', a, b), 1)), 'options->lower_hadd64 || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1039 (('urhadd@64', a, b), ('isub', ('ior', a, b), ('ushr', ('ixor', a, b), 1)), 'options->lower_hadd64 || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1040
1041 (('uadd_sat@64', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1042 (('uadd_sat', a, b), ('bcsel', ('ult', ('iadd', a, b), a), -1, ('iadd', a, b)), 'options->lower_add_sat'),
1043 (('usub_sat', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_add_sat'),
1044 (('usub_sat@64', a, b), ('bcsel', ('ult', a, b), 0, ('isub', a, b)), 'options->lower_usub_sat64 || (options->lower_int64_options & nir_lower_iadd64) != 0'),
1045
1046 # int64_t sum = a + b;
1047 #
1048 # if (a < 0 && b < 0 && a < sum)
1049 # sum = INT64_MIN;
1050 # } else if (a >= 0 && b >= 0 && sum < a)
1051 # sum = INT64_MAX;
1052 # }
1053 #
1054 # A couple optimizations are applied.
1055 #
1056 # 1. a < sum => sum >= 0. This replacement works because it is known that
1057 # a < 0 and b < 0, so sum should also be < 0 unless there was
1058 # underflow.
1059 #
1060 # 2. sum < a => sum < 0. This replacement works because it is known that
1061 # a >= 0 and b >= 0, so sum should also be >= 0 unless there was
1062 # overflow.
1063 #
1064 # 3. Invert the second if-condition and swap the order of parameters for
1065 # the bcsel. !(a >= 0 && b >= 0 && sum < 0) becomes !(a >= 0) || !(b >=
1066 # 0) || !(sum < 0), and that becomes (a < 0) || (b < 0) || (sum >= 0)
1067 #
1068 # On Intel Gen11, this saves ~11 instructions.
1069 (('iadd_sat@64', a, b), ('bcsel',
1070 ('iand', ('iand', ('ilt', a, 0), ('ilt', b, 0)), ('ige', ('iadd', a, b), 0)),
1071 0x8000000000000000,
1072 ('bcsel',
1073 ('ior', ('ior', ('ilt', a, 0), ('ilt', b, 0)), ('ige', ('iadd', a, b), 0)),
1074 ('iadd', a, b),
1075 0x7fffffffffffffff)),
1076 '(options->lower_int64_options & nir_lower_iadd64) != 0'),
1077
1078 # int64_t sum = a - b;
1079 #
1080 # if (a < 0 && b >= 0 && a < sum)
1081 # sum = INT64_MIN;
1082 # } else if (a >= 0 && b < 0 && a >= sum)
1083 # sum = INT64_MAX;
1084 # }
1085 #
1086 # Optimizations similar to the iadd_sat case are applied here.
1087 (('isub_sat@64', a, b), ('bcsel',
1088 ('iand', ('iand', ('ilt', a, 0), ('ige', b, 0)), ('ige', ('isub', a, b), 0)),
1089 0x8000000000000000,
1090 ('bcsel',
1091 ('ior', ('ior', ('ilt', a, 0), ('ige', b, 0)), ('ige', ('isub', a, b), 0)),
1092 ('isub', a, b),
1093 0x7fffffffffffffff)),
1094 '(options->lower_int64_options & nir_lower_iadd64) != 0'),
1095
1096 # These are done here instead of in the backend because the int64 lowering
1097 # pass will make a mess of the patterns. The first patterns are
1098 # conditioned on nir_lower_minmax64 because it was not clear that it was
1099 # always an improvement on platforms that have real int64 support. No
1100 # shaders in shader-db hit this, so it was hard to say one way or the
1101 # other.
1102 (('ilt', ('imax(is_used_once)', 'a@64', 'b@64'), 0), ('ilt', ('imax', ('unpack_64_2x32_split_y', a), ('unpack_64_2x32_split_y', b)), 0), '(options->lower_int64_options & nir_lower_minmax64) != 0'),
1103 (('ilt', ('imin(is_used_once)', 'a@64', 'b@64'), 0), ('ilt', ('imin', ('unpack_64_2x32_split_y', a), ('unpack_64_2x32_split_y', b)), 0), '(options->lower_int64_options & nir_lower_minmax64) != 0'),
1104 (('ige', ('imax(is_used_once)', 'a@64', 'b@64'), 0), ('ige', ('imax', ('unpack_64_2x32_split_y', a), ('unpack_64_2x32_split_y', b)), 0), '(options->lower_int64_options & nir_lower_minmax64) != 0'),
1105 (('ige', ('imin(is_used_once)', 'a@64', 'b@64'), 0), ('ige', ('imin', ('unpack_64_2x32_split_y', a), ('unpack_64_2x32_split_y', b)), 0), '(options->lower_int64_options & nir_lower_minmax64) != 0'),
1106 (('ilt', 'a@64', 0), ('ilt', ('unpack_64_2x32_split_y', a), 0), '(options->lower_int64_options & nir_lower_icmp64) != 0'),
1107 (('ige', 'a@64', 0), ('ige', ('unpack_64_2x32_split_y', a), 0), '(options->lower_int64_options & nir_lower_icmp64) != 0'),
1108
1109 (('ine', 'a@64', 0), ('ine', ('ior', ('unpack_64_2x32_split_x', a), ('unpack_64_2x32_split_y', a)), 0), '(options->lower_int64_options & nir_lower_icmp64) != 0'),
1110 (('ieq', 'a@64', 0), ('ieq', ('ior', ('unpack_64_2x32_split_x', a), ('unpack_64_2x32_split_y', a)), 0), '(options->lower_int64_options & nir_lower_icmp64) != 0'),
1111 # 0u < uint(a) <=> uint(a) != 0u
1112 (('ult', 0, 'a@64'), ('ine', ('ior', ('unpack_64_2x32_split_x', a), ('unpack_64_2x32_split_y', a)), 0), '(options->lower_int64_options & nir_lower_icmp64) != 0'),
1113
1114 # Alternative lowering that doesn't rely on bfi.
1115 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
1116 ('bcsel', ('ult', 31, 'bits'),
1117 'insert',
1118 (('ior',
1119 ('iand', 'base', ('inot', ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))),
1120 ('iand', ('ishl', 'insert', 'offset'), ('ishl', ('isub', ('ishl', 1, 'bits'), 1), 'offset'))))),
1121 'options->lower_bitfield_insert_to_shifts'),
1122
1123 # Alternative lowering that uses bitfield_select.
1124 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
1125 ('bcsel', ('ult', 31, 'bits'), 'insert',
1126 ('bitfield_select', ('bfm', 'bits', 'offset'), ('ishl', 'insert', 'offset'), 'base')),
1127 'options->lower_bitfield_insert_to_bitfield_select'),
1128
1129 (('ibitfield_extract', 'value', 'offset', 'bits'),
1130 ('bcsel', ('ult', 31, 'bits'), 'value',
1131 ('ibfe', 'value', 'offset', 'bits')),
1132 'options->lower_bitfield_extract'),
1133
1134 (('ubitfield_extract', 'value', 'offset', 'bits'),
1135 ('bcsel', ('ult', 31, 'bits'), 'value',
1136 ('ubfe', 'value', 'offset', 'bits')),
1137 'options->lower_bitfield_extract'),
1138
1139 # Note that these opcodes are defined to only use the five least significant bits of 'offset' and 'bits'
1140 (('ubfe', 'value', 'offset', ('iand', 31, 'bits')), ('ubfe', 'value', 'offset', 'bits')),
1141 (('ubfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ubfe', 'value', 'offset', 'bits')),
1142 (('ibfe', 'value', 'offset', ('iand', 31, 'bits')), ('ibfe', 'value', 'offset', 'bits')),
1143 (('ibfe', 'value', ('iand', 31, 'offset'), 'bits'), ('ibfe', 'value', 'offset', 'bits')),
1144 (('bfm', 'bits', ('iand', 31, 'offset')), ('bfm', 'bits', 'offset')),
1145 (('bfm', ('iand', 31, 'bits'), 'offset'), ('bfm', 'bits', 'offset')),
1146
1147 (('ibitfield_extract', 'value', 'offset', 'bits'),
1148 ('bcsel', ('ieq', 0, 'bits'),
1149 0,
1150 ('ishr',
1151 ('ishl', 'value', ('isub', ('isub', 32, 'bits'), 'offset')),
1152 ('isub', 32, 'bits'))),
1153 'options->lower_bitfield_extract_to_shifts'),
1154
1155 (('ubitfield_extract', 'value', 'offset', 'bits'),
1156 ('iand',
1157 ('ushr', 'value', 'offset'),
1158 ('bcsel', ('ieq', 'bits', 32),
1159 0xffffffff,
1160 ('isub', ('ishl', 1, 'bits'), 1))),
1161 'options->lower_bitfield_extract_to_shifts'),
1162
1163 (('ifind_msb', 'value'),
1164 ('ufind_msb', ('bcsel', ('ilt', 'value', 0), ('inot', 'value'), 'value')),
1165 'options->lower_ifind_msb'),
1166
1167 (('find_lsb', 'value'),
1168 ('ufind_msb', ('iand', 'value', ('ineg', 'value'))),
1169 'options->lower_find_lsb'),
1170
1171 (('extract_i8', a, 'b@32'),
1172 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
1173 'options->lower_extract_byte'),
1174
1175 (('extract_u8', a, 'b@32'),
1176 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
1177 'options->lower_extract_byte'),
1178
1179 (('extract_i16', a, 'b@32'),
1180 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
1181 'options->lower_extract_word'),
1182
1183 (('extract_u16', a, 'b@32'),
1184 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
1185 'options->lower_extract_word'),
1186
1187 (('pack_unorm_2x16', 'v'),
1188 ('pack_uvec2_to_uint',
1189 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
1190 'options->lower_pack_unorm_2x16'),
1191
1192 (('pack_unorm_4x8', 'v'),
1193 ('pack_uvec4_to_uint',
1194 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
1195 'options->lower_pack_unorm_4x8'),
1196
1197 (('pack_snorm_2x16', 'v'),
1198 ('pack_uvec2_to_uint',
1199 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
1200 'options->lower_pack_snorm_2x16'),
1201
1202 (('pack_snorm_4x8', 'v'),
1203 ('pack_uvec4_to_uint',
1204 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
1205 'options->lower_pack_snorm_4x8'),
1206
1207 (('unpack_unorm_2x16', 'v'),
1208 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
1209 ('extract_u16', 'v', 1))),
1210 65535.0),
1211 'options->lower_unpack_unorm_2x16'),
1212
1213 (('unpack_unorm_4x8', 'v'),
1214 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
1215 ('extract_u8', 'v', 1),
1216 ('extract_u8', 'v', 2),
1217 ('extract_u8', 'v', 3))),
1218 255.0),
1219 'options->lower_unpack_unorm_4x8'),
1220
1221 (('unpack_snorm_2x16', 'v'),
1222 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
1223 ('extract_i16', 'v', 1))),
1224 32767.0))),
1225 'options->lower_unpack_snorm_2x16'),
1226
1227 (('unpack_snorm_4x8', 'v'),
1228 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
1229 ('extract_i8', 'v', 1),
1230 ('extract_i8', 'v', 2),
1231 ('extract_i8', 'v', 3))),
1232 127.0))),
1233 'options->lower_unpack_snorm_4x8'),
1234
1235 (('pack_half_2x16_split', 'a@32', 'b@32'),
1236 ('ior', ('ishl', ('u2u32', ('f2f16', b)), 16), ('u2u32', ('f2f16', a))),
1237 'options->lower_pack_half_2x16_split'),
1238
1239 (('unpack_half_2x16_split_x', 'a@32'),
1240 ('f2f32', ('u2u16', a)),
1241 'options->lower_unpack_half_2x16_split'),
1242
1243 (('unpack_half_2x16_split_y', 'a@32'),
1244 ('f2f32', ('u2u16', ('ushr', a, 16))),
1245 'options->lower_unpack_half_2x16_split'),
1246
1247 (('isign', a), ('imin', ('imax', a, -1), 1), 'options->lower_isign'),
1248 (('fsign', a), ('fsub', ('b2f', ('flt', 0.0, a)), ('b2f', ('flt', a, 0.0))), 'options->lower_fsign'),
1249
1250 # Address/offset calculations:
1251 # Drivers supporting imul24 should use the nir_lower_amul() pass, this
1252 # rule converts everyone else to imul:
1253 (('amul', a, b), ('imul', a, b), '!options->has_imul24'),
1254
1255 (('imad24_ir3', a, b, 0), ('imul24', a, b)),
1256 (('imad24_ir3', a, 0, c), (c)),
1257 (('imad24_ir3', a, 1, c), ('iadd', a, c)),
1258
1259 # if first two srcs are const, crack apart the imad so constant folding
1260 # can clean up the imul:
1261 # TODO ffma should probably get a similar rule:
1262 (('imad24_ir3', '#a', '#b', c), ('iadd', ('imul', a, b), c)),
1263
1264 # These will turn 24b address/offset calc back into 32b shifts, but
1265 # it should be safe to get back some of the bits of precision that we
1266 # already decided were no necessary:
1267 (('imul24', a, '#b@32(is_pos_power_of_two)'), ('ishl', a, ('find_lsb', b)), '!options->lower_bitops'),
1268 (('imul24', a, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a, ('find_lsb', ('iabs', b)))), '!options->lower_bitops'),
1269 (('imul24', a, 0), (0)),
1270 ])
1271
1272 # bit_size dependent lowerings
1273 for bit_size in [8, 16, 32, 64]:
1274 # convenience constants
1275 intmax = (1 << (bit_size - 1)) - 1
1276 intmin = 1 << (bit_size - 1)
1277
1278 optimizations += [
1279 (('iadd_sat@' + str(bit_size), a, b),
1280 ('bcsel', ('ige', b, 1), ('bcsel', ('ilt', ('iadd', a, b), a), intmax, ('iadd', a, b)),
1281 ('bcsel', ('ilt', a, ('iadd', a, b)), intmin, ('iadd', a, b))), 'options->lower_add_sat'),
1282 (('isub_sat@' + str(bit_size), a, b),
1283 ('bcsel', ('ilt', b, 0), ('bcsel', ('ilt', ('isub', a, b), a), intmax, ('isub', a, b)),
1284 ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'),
1285 ]
1286
1287 invert = OrderedDict([('feq', 'fne'), ('fne', 'feq')])
1288
1289 for left, right in itertools.combinations_with_replacement(invert.keys(), 2):
1290 optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))),
1291 ('iand', (invert[left], a, b), (invert[right], c, d))))
1292 optimizations.append((('inot', ('iand(is_used_once)', (left, a, b), (right, c, d))),
1293 ('ior', (invert[left], a, b), (invert[right], c, d))))
1294
1295 # Optimize x2bN(b2x(x)) -> x
1296 for size in type_sizes('bool'):
1297 aN = 'a@' + str(size)
1298 f2bN = 'f2b' + str(size)
1299 i2bN = 'i2b' + str(size)
1300 optimizations.append(((f2bN, ('b2f', aN)), a))
1301 optimizations.append(((i2bN, ('b2i', aN)), a))
1302
1303 # Optimize x2yN(b2x(x)) -> b2y
1304 for x, y in itertools.product(['f', 'u', 'i'], ['f', 'u', 'i']):
1305 if x != 'f' and y != 'f' and x != y:
1306 continue
1307
1308 b2x = 'b2f' if x == 'f' else 'b2i'
1309 b2y = 'b2f' if y == 'f' else 'b2i'
1310 x2yN = '{}2{}'.format(x, y)
1311 optimizations.append(((x2yN, (b2x, a)), (b2y, a)))
1312
1313 # Optimize away x2xN(a@N)
1314 for t in ['int', 'uint', 'float']:
1315 for N in type_sizes(t):
1316 x2xN = '{0}2{0}{1}'.format(t[0], N)
1317 aN = 'a@{0}'.format(N)
1318 optimizations.append(((x2xN, aN), a))
1319
1320 # Optimize x2xN(y2yM(a@P)) -> y2yN(a) for integers
1321 # In particular, we can optimize away everything except upcast of downcast and
1322 # upcasts where the type differs from the other cast
1323 for N, M in itertools.product(type_sizes('uint'), type_sizes('uint')):
1324 if N < M:
1325 # The outer cast is a down-cast. It doesn't matter what the size of the
1326 # argument of the inner cast is because we'll never been in the upcast
1327 # of downcast case. Regardless of types, we'll always end up with y2yN
1328 # in the end.
1329 for x, y in itertools.product(['i', 'u'], ['i', 'u']):
1330 x2xN = '{0}2{0}{1}'.format(x, N)
1331 y2yM = '{0}2{0}{1}'.format(y, M)
1332 y2yN = '{0}2{0}{1}'.format(y, N)
1333 optimizations.append(((x2xN, (y2yM, a)), (y2yN, a)))
1334 elif N > M:
1335 # If the outer cast is an up-cast, we have to be more careful about the
1336 # size of the argument of the inner cast and with types. In this case,
1337 # the type is always the type of type up-cast which is given by the
1338 # outer cast.
1339 for P in type_sizes('uint'):
1340 # We can't optimize away up-cast of down-cast.
1341 if M < P:
1342 continue
1343
1344 # Because we're doing down-cast of down-cast, the types always have
1345 # to match between the two casts
1346 for x in ['i', 'u']:
1347 x2xN = '{0}2{0}{1}'.format(x, N)
1348 x2xM = '{0}2{0}{1}'.format(x, M)
1349 aP = 'a@{0}'.format(P)
1350 optimizations.append(((x2xN, (x2xM, aP)), (x2xN, a)))
1351 else:
1352 # The N == M case is handled by other optimizations
1353 pass
1354
1355 # Optimize comparisons with up-casts
1356 for t in ['int', 'uint', 'float']:
1357 for N, M in itertools.product(type_sizes(t), repeat=2):
1358 if N == 1 or N >= M:
1359 continue
1360
1361 x2xM = '{0}2{0}{1}'.format(t[0], M)
1362 x2xN = '{0}2{0}{1}'.format(t[0], N)
1363 aN = 'a@' + str(N)
1364 bN = 'b@' + str(N)
1365 xeq = 'feq' if t == 'float' else 'ieq'
1366 xne = 'fne' if t == 'float' else 'ine'
1367 xge = '{0}ge'.format(t[0])
1368 xlt = '{0}lt'.format(t[0])
1369
1370 # Up-casts are lossless so for correctly signed comparisons of
1371 # up-casted values we can do the comparison at the largest of the two
1372 # original sizes and drop one or both of the casts. (We have
1373 # optimizations to drop the no-op casts which this may generate.)
1374 for P in type_sizes(t):
1375 if P == 1 or P > N:
1376 continue
1377
1378 bP = 'b@' + str(P)
1379 optimizations += [
1380 ((xeq, (x2xM, aN), (x2xM, bP)), (xeq, a, (x2xN, b))),
1381 ((xne, (x2xM, aN), (x2xM, bP)), (xne, a, (x2xN, b))),
1382 ((xge, (x2xM, aN), (x2xM, bP)), (xge, a, (x2xN, b))),
1383 ((xlt, (x2xM, aN), (x2xM, bP)), (xlt, a, (x2xN, b))),
1384 ((xge, (x2xM, bP), (x2xM, aN)), (xge, (x2xN, b), a)),
1385 ((xlt, (x2xM, bP), (x2xM, aN)), (xlt, (x2xN, b), a)),
1386 ]
1387
1388 # The next bit doesn't work on floats because the range checks would
1389 # get way too complicated.
1390 if t in ['int', 'uint']:
1391 if t == 'int':
1392 xN_min = -(1 << (N - 1))
1393 xN_max = (1 << (N - 1)) - 1
1394 elif t == 'uint':
1395 xN_min = 0
1396 xN_max = (1 << N) - 1
1397 else:
1398 assert False
1399
1400 # If we're up-casting and comparing to a constant, we can unfold
1401 # the comparison into a comparison with the shrunk down constant
1402 # and a check that the constant fits in the smaller bit size.
1403 optimizations += [
1404 ((xeq, (x2xM, aN), '#b'),
1405 ('iand', (xeq, a, (x2xN, b)), (xeq, (x2xM, (x2xN, b)), b))),
1406 ((xne, (x2xM, aN), '#b'),
1407 ('ior', (xne, a, (x2xN, b)), (xne, (x2xM, (x2xN, b)), b))),
1408 ((xlt, (x2xM, aN), '#b'),
1409 ('iand', (xlt, xN_min, b),
1410 ('ior', (xlt, xN_max, b), (xlt, a, (x2xN, b))))),
1411 ((xlt, '#a', (x2xM, bN)),
1412 ('iand', (xlt, a, xN_max),
1413 ('ior', (xlt, a, xN_min), (xlt, (x2xN, a), b)))),
1414 ((xge, (x2xM, aN), '#b'),
1415 ('iand', (xge, xN_max, b),
1416 ('ior', (xge, xN_min, b), (xge, a, (x2xN, b))))),
1417 ((xge, '#a', (x2xM, bN)),
1418 ('iand', (xge, a, xN_min),
1419 ('ior', (xge, a, xN_max), (xge, (x2xN, a), b)))),
1420 ]
1421
1422 def fexp2i(exp, bits):
1423 # We assume that exp is already in the right range.
1424 if bits == 16:
1425 return ('i2i16', ('ishl', ('iadd', exp, 15), 10))
1426 elif bits == 32:
1427 return ('ishl', ('iadd', exp, 127), 23)
1428 elif bits == 64:
1429 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20))
1430 else:
1431 assert False
1432
1433 def ldexp(f, exp, bits):
1434 # First, we clamp exp to a reasonable range. The maximum possible range
1435 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
1436 # a maximum range of [-149, 127]. This means that we can potentially have
1437 # a swing of +-276. If you start with FLT_MAX, you actually have to do
1438 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
1439 # spec, on the other hand, only requires that we handle an exponent value
1440 # in the range [-126, 128]. This implementation is *mostly* correct; it
1441 # handles a range on exp of [-252, 254] which allows you to create any
1442 # value (including denorms if the hardware supports it) and to adjust the
1443 # exponent of any normal value to anything you want.
1444 if bits == 16:
1445 exp = ('imin', ('imax', exp, -28), 30)
1446 elif bits == 32:
1447 exp = ('imin', ('imax', exp, -252), 254)
1448 elif bits == 64:
1449 exp = ('imin', ('imax', exp, -2044), 2046)
1450 else:
1451 assert False
1452
1453 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
1454 # (We use ishr which isn't the same for -1, but the -1 case still works
1455 # since we use exp-exp/2 as the second exponent.) While the spec
1456 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
1457 # work with denormals and doesn't allow for the full swing in exponents
1458 # that you can get with normalized values. Instead, we create two powers
1459 # of two and multiply by them each in turn. That way the effective range
1460 # of our exponent is doubled.
1461 pow2_1 = fexp2i(('ishr', exp, 1), bits)
1462 pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits)
1463 return ('fmul', ('fmul', f, pow2_1), pow2_2)
1464
1465 optimizations += [
1466 (('ldexp@16', 'x', 'exp'), ldexp('x', 'exp', 16), 'options->lower_ldexp'),
1467 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32), 'options->lower_ldexp'),
1468 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64), 'options->lower_ldexp'),
1469 ]
1470
1471 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
1472 def bitfield_reverse(u):
1473 step1 = ('ior', ('ishl', u, 16), ('ushr', u, 16))
1474 step2 = ('ior', ('ishl', ('iand', step1, 0x00ff00ff), 8), ('ushr', ('iand', step1, 0xff00ff00), 8))
1475 step3 = ('ior', ('ishl', ('iand', step2, 0x0f0f0f0f), 4), ('ushr', ('iand', step2, 0xf0f0f0f0), 4))
1476 step4 = ('ior', ('ishl', ('iand', step3, 0x33333333), 2), ('ushr', ('iand', step3, 0xcccccccc), 2))
1477 step5 = ('ior(many-comm-expr)', ('ishl', ('iand', step4, 0x55555555), 1), ('ushr', ('iand', step4, 0xaaaaaaaa), 1))
1478
1479 return step5
1480
1481 optimizations += [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'), '!options->lower_bitfield_reverse')]
1482
1483 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
1484 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
1485 # and, if a is a NaN then the second comparison will fail anyway.
1486 for op in ['flt', 'fge', 'feq']:
1487 optimizations += [
1488 (('iand', ('feq', a, a), (op, a, b)), ('!' + op, a, b)),
1489 (('iand', ('feq', a, a), (op, b, a)), ('!' + op, b, a)),
1490 ]
1491
1492 # Add optimizations to handle the case where the result of a ternary is
1493 # compared to a constant. This way we can take things like
1494 #
1495 # (a ? 0 : 1) > 0
1496 #
1497 # and turn it into
1498 #
1499 # a ? (0 > 0) : (1 > 0)
1500 #
1501 # which constant folding will eat for lunch. The resulting ternary will
1502 # further get cleaned up by the boolean reductions above and we will be
1503 # left with just the original variable "a".
1504 for op in ['flt', 'fge', 'feq', 'fne',
1505 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
1506 optimizations += [
1507 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
1508 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
1509 ((op, '#d', ('bcsel', a, '#b', '#c')),
1510 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
1511 ]
1512
1513
1514 # For example, this converts things like
1515 #
1516 # 1 + mix(0, a - 1, condition)
1517 #
1518 # into
1519 #
1520 # mix(1, (a-1)+1, condition)
1521 #
1522 # Other optimizations will rearrange the constants.
1523 for op in ['fadd', 'fmul', 'iadd', 'imul']:
1524 optimizations += [
1525 ((op, ('bcsel(is_used_once)', a, '#b', c), '#d'), ('bcsel', a, (op, b, d), (op, c, d)))
1526 ]
1527
1528 # For derivatives in compute shaders, GLSL_NV_compute_shader_derivatives
1529 # states:
1530 #
1531 # If neither layout qualifier is specified, derivatives in compute shaders
1532 # return zero, which is consistent with the handling of built-in texture
1533 # functions like texture() in GLSL 4.50 compute shaders.
1534 for op in ['fddx', 'fddx_fine', 'fddx_coarse',
1535 'fddy', 'fddy_fine', 'fddy_coarse']:
1536 optimizations += [
1537 ((op, 'a'), 0.0, 'info->stage == MESA_SHADER_COMPUTE && info->cs.derivative_group == DERIVATIVE_GROUP_NONE')
1538 ]
1539
1540 # Some optimizations for ir3-specific instructions.
1541 optimizations += [
1542 # 'al * bl': If either 'al' or 'bl' is zero, return zero.
1543 (('umul_low', '#a(is_lower_half_zero)', 'b'), (0)),
1544 # '(ah * bl) << 16 + c': If either 'ah' or 'bl' is zero, return 'c'.
1545 (('imadsh_mix16', '#a@32(is_lower_half_zero)', 'b@32', 'c@32'), ('c')),
1546 (('imadsh_mix16', 'a@32', '#b@32(is_upper_half_zero)', 'c@32'), ('c')),
1547 ]
1548
1549 # These kinds of sequences can occur after nir_opt_peephole_select.
1550 #
1551 # NOTE: fadd is not handled here because that gets in the way of ffma
1552 # generation in the i965 driver. Instead, fadd and ffma are handled in
1553 # late_optimizations.
1554
1555 for op in ['flrp']:
1556 optimizations += [
1557 (('bcsel', a, (op + '(is_used_once)', b, c, d), (op, b, c, e)), (op, b, c, ('bcsel', a, d, e))),
1558 (('bcsel', a, (op, b, c, d), (op + '(is_used_once)', b, c, e)), (op, b, c, ('bcsel', a, d, e))),
1559 (('bcsel', a, (op + '(is_used_once)', b, c, d), (op, b, e, d)), (op, b, ('bcsel', a, c, e), d)),
1560 (('bcsel', a, (op, b, c, d), (op + '(is_used_once)', b, e, d)), (op, b, ('bcsel', a, c, e), d)),
1561 (('bcsel', a, (op + '(is_used_once)', b, c, d), (op, e, c, d)), (op, ('bcsel', a, b, e), c, d)),
1562 (('bcsel', a, (op, b, c, d), (op + '(is_used_once)', e, c, d)), (op, ('bcsel', a, b, e), c, d)),
1563 ]
1564
1565 for op in ['fmul', 'iadd', 'imul', 'iand', 'ior', 'ixor', 'fmin', 'fmax', 'imin', 'imax', 'umin', 'umax']:
1566 optimizations += [
1567 (('bcsel', a, (op + '(is_used_once)', b, c), (op, b, 'd(is_not_const)')), (op, b, ('bcsel', a, c, d))),
1568 (('bcsel', a, (op + '(is_used_once)', b, 'c(is_not_const)'), (op, b, d)), (op, b, ('bcsel', a, c, d))),
1569 (('bcsel', a, (op, b, 'c(is_not_const)'), (op + '(is_used_once)', b, d)), (op, b, ('bcsel', a, c, d))),
1570 (('bcsel', a, (op, b, c), (op + '(is_used_once)', b, 'd(is_not_const)')), (op, b, ('bcsel', a, c, d))),
1571 ]
1572
1573 for op in ['fpow']:
1574 optimizations += [
1575 (('bcsel', a, (op + '(is_used_once)', b, c), (op, b, d)), (op, b, ('bcsel', a, c, d))),
1576 (('bcsel', a, (op, b, c), (op + '(is_used_once)', b, d)), (op, b, ('bcsel', a, c, d))),
1577 (('bcsel', a, (op + '(is_used_once)', b, c), (op, d, c)), (op, ('bcsel', a, b, d), c)),
1578 (('bcsel', a, (op, b, c), (op + '(is_used_once)', d, c)), (op, ('bcsel', a, b, d), c)),
1579 ]
1580
1581 for op in ['frcp', 'frsq', 'fsqrt', 'fexp2', 'flog2', 'fsign', 'fsin', 'fcos']:
1582 optimizations += [
1583 (('bcsel', a, (op + '(is_used_once)', b), (op, c)), (op, ('bcsel', a, b, c))),
1584 (('bcsel', a, (op, b), (op + '(is_used_once)', c)), (op, ('bcsel', a, b, c))),
1585 ]
1586
1587 # This section contains "late" optimizations that should be run before
1588 # creating ffmas and calling regular optimizations for the final time.
1589 # Optimizations should go here if they help code generation and conflict
1590 # with the regular optimizations.
1591 before_ffma_optimizations = [
1592 # Propagate constants down multiplication chains
1593 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a, c), b)),
1594 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a, c), b)),
1595 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a, c), b)),
1596 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a, c), b)),
1597
1598 (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
1599 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
1600 (('~fadd', ('fneg', a), a), 0.0),
1601 (('iadd', ('ineg', a), a), 0),
1602 (('iadd', ('ineg', a), ('iadd', a, b)), b),
1603 (('iadd', a, ('iadd', ('ineg', a), b)), b),
1604 (('~fadd', ('fneg', a), ('fadd', a, b)), b),
1605 (('~fadd', a, ('fadd', ('fneg', a), b)), b),
1606
1607 (('~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)),
1608 (('~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)),
1609 (('~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))),
1610 ]
1611
1612 # This section contains "late" optimizations that should be run after the
1613 # regular optimizations have finished. Optimizations should go here if
1614 # they help code generation but do not necessarily produce code that is
1615 # more easily optimizable.
1616 late_optimizations = [
1617 # Most of these optimizations aren't quite safe when you get infinity or
1618 # Nan involved but the first one should be fine.
1619 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
1620 (('flt', ('fneg', ('fadd', a, b)), 0.0), ('flt', ('fneg', a), b)),
1621 (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
1622 (('~fge', ('fneg', ('fadd', a, b)), 0.0), ('fge', ('fneg', a), b)),
1623 (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
1624 (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
1625
1626 # nir_lower_to_source_mods will collapse this, but its existence during the
1627 # optimization loop can prevent other optimizations.
1628 (('fneg', ('fneg', a)), a),
1629
1630 # Subtractions get lowered during optimization, so we need to recombine them
1631 (('fadd', 'a', ('fneg', 'b')), ('fsub', 'a', 'b'), '!options->lower_sub'),
1632 (('iadd', 'a', ('ineg', 'b')), ('isub', 'a', 'b'), '!options->lower_sub'),
1633 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
1634 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
1635
1636 # These are duplicated from the main optimizations table. The late
1637 # patterns that rearrange expressions like x - .5 < 0 to x < .5 can create
1638 # new patterns like these. The patterns that compare with zero are removed
1639 # because they are unlikely to be created in by anything in
1640 # late_optimizations.
1641 (('flt', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('flt', a, b)),
1642 (('flt', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('flt', b, a)),
1643 (('fge', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fge', a, b)),
1644 (('fge', '#b(is_gt_0_and_lt_1)', ('fsat(is_used_once)', a)), ('fge', b, a)),
1645 (('feq', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('feq', a, b)),
1646 (('fne', ('fsat(is_used_once)', a), '#b(is_gt_0_and_lt_1)'), ('fne', a, b)),
1647
1648 (('fge', ('fsat(is_used_once)', a), 1.0), ('fge', a, 1.0)),
1649 (('flt', ('fsat(is_used_once)', a), 1.0), ('flt', a, 1.0)),
1650
1651 (('~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)))),
1652
1653 (('flt', ('fneg', a), ('fneg', b)), ('flt', b, a)),
1654 (('fge', ('fneg', a), ('fneg', b)), ('fge', b, a)),
1655 (('feq', ('fneg', a), ('fneg', b)), ('feq', b, a)),
1656 (('fne', ('fneg', a), ('fneg', b)), ('fne', b, a)),
1657 (('flt', ('fneg', a), -1.0), ('flt', 1.0, a)),
1658 (('flt', -1.0, ('fneg', a)), ('flt', a, 1.0)),
1659 (('fge', ('fneg', a), -1.0), ('fge', 1.0, a)),
1660 (('fge', -1.0, ('fneg', a)), ('fge', a, 1.0)),
1661 (('fne', ('fneg', a), -1.0), ('fne', 1.0, a)),
1662 (('feq', -1.0, ('fneg', a)), ('feq', a, 1.0)),
1663
1664 (('ior', a, a), a),
1665 (('iand', a, a), a),
1666
1667 (('~fadd', ('fneg(is_used_once)', ('fsat(is_used_once)', 'a(is_not_fmul)')), 1.0), ('fsat', ('fadd', 1.0, ('fneg', a)))),
1668
1669 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
1670 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
1671 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
1672 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
1673
1674 (('~flrp@32', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1675 (('~flrp@64', ('fadd(is_used_once)', a, b), ('fadd(is_used_once)', a, c), d), ('fadd', ('flrp', b, c, d), a)),
1676
1677 (('~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'),
1678 (('~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'),
1679
1680 # A similar operation could apply to any ffma(#a, b, #(-a/2)), but this
1681 # particular operation is common for expanding values stored in a texture
1682 # from [0,1] to [-1,1].
1683 (('~ffma@32', a, 2.0, -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1684 (('~ffma@32', a, -2.0, -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1685 (('~ffma@32', a, -2.0, 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1686 (('~ffma@32', a, 2.0, 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1687 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), -1.0), ('flrp', -1.0, 1.0, a ), '!options->lower_flrp32'),
1688 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), -1.0), ('flrp', -1.0, 1.0, ('fneg', a)), '!options->lower_flrp32'),
1689 (('~fadd@32', ('fmul(is_used_once)', -2.0, a), 1.0), ('flrp', 1.0, -1.0, a ), '!options->lower_flrp32'),
1690 (('~fadd@32', ('fmul(is_used_once)', 2.0, a), 1.0), ('flrp', 1.0, -1.0, ('fneg', a)), '!options->lower_flrp32'),
1691
1692 # flrp(a, b, a)
1693 # a*(1-a) + b*a
1694 # a + -a*a + a*b (1)
1695 # a + a*(b - a)
1696 # Option 1: ffma(a, (b-a), a)
1697 #
1698 # Alternately, after (1):
1699 # a*(1+b) + -a*a
1700 # a*((1+b) + -a)
1701 #
1702 # Let b=1
1703 #
1704 # Option 2: ffma(a, 2, -(a*a))
1705 # Option 3: ffma(a, 2, (-a)*a)
1706 # Option 4: ffma(a, -a, (2*a)
1707 # Option 5: a * (2 - a)
1708 #
1709 # There are a lot of other possible combinations.
1710 (('~ffma@32', ('fadd', b, ('fneg', a)), a, a), ('flrp', a, b, a), '!options->lower_flrp32'),
1711 (('~ffma@32', a, 2.0, ('fneg', ('fmul', a, a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1712 (('~ffma@32', a, 2.0, ('fmul', ('fneg', a), a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1713 (('~ffma@32', a, ('fneg', a), ('fmul', 2.0, a)), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1714 (('~fmul@32', a, ('fadd', 2.0, ('fneg', a))), ('flrp', a, 1.0, a), '!options->lower_flrp32'),
1715
1716 # we do these late so that we don't get in the way of creating ffmas
1717 (('fmin', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmin', a, b))),
1718 (('fmax', ('fadd(is_used_once)', '#c', a), ('fadd(is_used_once)', '#c', b)), ('fadd', c, ('fmax', a, b))),
1719
1720 (('bcsel', a, 0, ('b2f32', ('inot', 'b@bool'))), ('b2f32', ('inot', ('ior', a, b)))),
1721
1722 # Putting this in 'optimizations' interferes with the bcsel(a, op(b, c),
1723 # op(b, d)) => op(b, bcsel(a, c, d)) transformations. I do not know why.
1724 (('bcsel', ('feq', ('fsqrt', 'a(is_not_negative)'), 0.0), intBitsToFloat(0x7f7fffff), ('frsq', a)),
1725 ('fmin', ('frsq', a), intBitsToFloat(0x7f7fffff))),
1726
1727 # Things that look like DPH in the source shader may get expanded to
1728 # something that looks like dot(v1.xyz, v2.xyz) + v1.w by the time it gets
1729 # to NIR. After FFMA is generated, this can look like:
1730 #
1731 # fadd(ffma(v1.z, v2.z, ffma(v1.y, v2.y, fmul(v1.x, v2.x))), v1.w)
1732 #
1733 # Reassociate the last addition into the first multiplication.
1734 #
1735 # Some shaders do not use 'invariant' in vertex and (possibly) geometry
1736 # shader stages on some outputs that are intended to be invariant. For
1737 # various reasons, this optimization may not be fully applied in all
1738 # shaders used for different rendering passes of the same geometry. This
1739 # can result in Z-fighting artifacts (at best). For now, disable this
1740 # optimization in these stages. See bugzilla #111490. In tessellation
1741 # stages applications seem to use 'precise' when necessary, so allow the
1742 # optimization in those stages.
1743 (('~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)'),
1744 ('ffma', a, b, ('ffma', c, d, ('ffma', e, 'f', 'g'))), '(info->stage != MESA_SHADER_VERTEX && info->stage != MESA_SHADER_GEOMETRY) && !options->intel_vec4'),
1745 (('~fadd', ('ffma(is_used_once)', a, b, ('fmul', 'c(is_not_const_and_not_fsign)', 'd(is_not_const_and_not_fsign)') ), 'e(is_not_const)'),
1746 ('ffma', a, b, ('ffma', c, d, e)), '(info->stage != MESA_SHADER_VERTEX && info->stage != MESA_SHADER_GEOMETRY) && !options->intel_vec4'),
1747
1748 # Convert f2fmp instructions to concrete f2f16 instructions. At this point
1749 # any conversions that could have been removed will have been removed in
1750 # nir_opt_algebraic so any remaining ones are required.
1751 (('f2fmp', a), ('f2f16', a)),
1752 ]
1753
1754 for op in ['fadd']:
1755 late_optimizations += [
1756 (('bcsel', a, (op + '(is_used_once)', b, c), (op, b, d)), (op, b, ('bcsel', a, c, d))),
1757 (('bcsel', a, (op, b, c), (op + '(is_used_once)', b, d)), (op, b, ('bcsel', a, c, d))),
1758 ]
1759
1760 for op in ['ffma']:
1761 late_optimizations += [
1762 (('bcsel', a, (op + '(is_used_once)', b, c, d), (op, b, c, e)), (op, b, c, ('bcsel', a, d, e))),
1763 (('bcsel', a, (op, b, c, d), (op + '(is_used_once)', b, c, e)), (op, b, c, ('bcsel', a, d, e))),
1764
1765 (('bcsel', a, (op + '(is_used_once)', b, c, d), (op, b, e, d)), (op, b, ('bcsel', a, c, e), d)),
1766 (('bcsel', a, (op, b, c, d), (op + '(is_used_once)', b, e, d)), (op, b, ('bcsel', a, c, e), d)),
1767 ]
1768
1769 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render())
1770 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_before_ffma",
1771 before_ffma_optimizations).render())
1772 print(nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
1773 late_optimizations).render())