Merge remote-tracking branch 'mesa-public/master' into vulkan
[mesa.git] / src / compiler / nir / nir_opt_algebraic.py
1 #! /usr/bin/env python
2 # -*- encoding: utf-8 -*-
3 #
4 # Copyright (C) 2014 Intel Corporation
5 #
6 # Permission is hereby granted, free of charge, to any person obtaining a
7 # copy of this software and associated documentation files (the "Software"),
8 # to deal in the Software without restriction, including without limitation
9 # the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 # and/or sell copies of the Software, and to permit persons to whom the
11 # Software is furnished to do so, subject to the following conditions:
12 #
13 # The above copyright notice and this permission notice (including the next
14 # paragraph) shall be included in all copies or substantial portions of the
15 # Software.
16 #
17 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
23 # IN THE SOFTWARE.
24 #
25 # Authors:
26 # Jason Ekstrand (jason@jlekstrand.net)
27
28 import nir_algebraic
29
30 # Convenience variables
31 a = 'a'
32 b = 'b'
33 c = 'c'
34 d = 'd'
35
36 # Written in the form (<search>, <replace>) where <search> is an expression
37 # and <replace> is either an expression or a value. An expression is
38 # defined as a tuple of the form (<op>, <src0>, <src1>, <src2>, <src3>)
39 # where each source is either an expression or a value. A value can be
40 # either a numeric constant or a string representing a variable name.
41 #
42 # Variable names are specified as "[#]name[@type]" where "#" inicates that
43 # the given variable will only match constants and the type indicates that
44 # the given variable will only match values from ALU instructions with the
45 # given output type.
46 #
47 # For constants, you have to be careful to make sure that it is the right
48 # type because python is unaware of the source and destination types of the
49 # opcodes.
50
51 optimizations = [
52 (('fneg', ('fneg', a)), a),
53 (('ineg', ('ineg', a)), a),
54 (('fabs', ('fabs', a)), ('fabs', a)),
55 (('fabs', ('fneg', a)), ('fabs', a)),
56 (('iabs', ('iabs', a)), ('iabs', a)),
57 (('iabs', ('ineg', a)), ('iabs', a)),
58 (('fadd', a, 0.0), a),
59 (('iadd', a, 0), a),
60 (('usadd_4x8', a, 0), a),
61 (('usadd_4x8', a, ~0), ~0),
62 (('fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
63 (('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
64 (('fadd', ('fneg', a), a), 0.0),
65 (('iadd', ('ineg', a), a), 0),
66 (('iadd', ('ineg', a), ('iadd', a, b)), b),
67 (('iadd', a, ('iadd', ('ineg', a), b)), b),
68 (('fadd', ('fneg', a), ('fadd', a, b)), b),
69 (('fadd', a, ('fadd', ('fneg', a), b)), b),
70 (('fmul', a, 0.0), 0.0),
71 (('imul', a, 0), 0),
72 (('umul_unorm_4x8', a, 0), 0),
73 (('umul_unorm_4x8', a, ~0), a),
74 (('fmul', a, 1.0), a),
75 (('imul', a, 1), a),
76 (('fmul', a, -1.0), ('fneg', a)),
77 (('imul', a, -1), ('ineg', a)),
78 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
79 (('ffma', 0.0, a, b), b),
80 (('ffma', a, 0.0, b), b),
81 (('ffma', a, b, 0.0), ('fmul', a, b)),
82 (('ffma', a, 1.0, b), ('fadd', a, b)),
83 (('ffma', 1.0, a, b), ('fadd', a, b)),
84 (('flrp', a, b, 0.0), a),
85 (('flrp', a, b, 1.0), b),
86 (('flrp', a, a, b), a),
87 (('flrp', 0.0, a, b), ('fmul', a, b)),
88 (('flrp', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp'),
89 (('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
90 (('fadd', ('fmul', a, ('fadd', 1.0, ('fneg', c))), ('fmul', b, c)), ('flrp', a, b, c), '!options->lower_flrp'),
91 (('fadd', a, ('fmul', c, ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp'),
92 (('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
93 (('fadd', ('fmul', a, b), c), ('ffma', a, b, c), '!options->lower_ffma'),
94 # Comparison simplifications
95 (('inot', ('flt', a, b)), ('fge', a, b)),
96 (('inot', ('fge', a, b)), ('flt', a, b)),
97 (('inot', ('feq', a, b)), ('fne', a, b)),
98 (('inot', ('fne', a, b)), ('feq', a, b)),
99 (('inot', ('ilt', a, b)), ('ige', a, b)),
100 (('inot', ('ige', a, b)), ('ilt', a, b)),
101 (('inot', ('ieq', a, b)), ('ine', a, b)),
102 (('inot', ('ine', a, b)), ('ieq', a, b)),
103 (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
104 (('bcsel', ('flt', a, b), a, b), ('fmin', a, b)),
105 (('bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
106 (('bcsel', ('inot', 'a@bool'), b, c), ('bcsel', a, c, b)),
107 (('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
108 (('fmin', a, a), a),
109 (('fmax', a, a), a),
110 (('imin', a, a), a),
111 (('imax', a, a), a),
112 (('umin', a, a), a),
113 (('umax', a, a), a),
114 (('fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
115 (('fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
116 (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
117 (('fsat', ('fsat', a)), ('fsat', a)),
118 (('fmin', ('fmax', ('fmin', ('fmax', a, 0.0), 1.0), 0.0), 1.0), ('fmin', ('fmax', a, 0.0), 1.0)),
119 (('ior', ('flt', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
120 (('ior', ('flt', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
121 (('ior', ('fge', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
122 (('ior', ('fge', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
123 (('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
124 (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
125 (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
126 (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'),
127 (('fne', ('fneg', a), a), ('fne', a, 0.0)),
128 (('feq', ('fneg', a), a), ('feq', a, 0.0)),
129 # Emulating booleans
130 (('imul', ('b2i', a), ('b2i', b)), ('b2i', ('iand', a, b))),
131 (('fmul', ('b2f', a), ('b2f', b)), ('b2f', ('iand', a, b))),
132 (('fsat', ('fadd', ('b2f', a), ('b2f', b))), ('b2f', ('ior', a, b))),
133 (('iand', 'a@bool', 1.0), ('b2f', a)),
134 (('flt', ('fneg', ('b2f', a)), 0), a), # Generated by TGSI KILL_IF.
135 (('flt', ('fsub', 0.0, ('b2f', a)), 0), a), # Generated by TGSI KILL_IF.
136 # Comparison with the same args. Note that these are not done for
137 # the float versions because NaN always returns false on float
138 # inequalities.
139 (('ilt', a, a), False),
140 (('ige', a, a), True),
141 (('ieq', a, a), True),
142 (('ine', a, a), False),
143 (('ult', a, a), False),
144 (('uge', a, a), True),
145 # Logical and bit operations
146 (('fand', a, 0.0), 0.0),
147 (('iand', a, a), a),
148 (('iand', a, ~0), a),
149 (('iand', a, 0), 0),
150 (('ior', a, a), a),
151 (('ior', a, 0), a),
152 (('fxor', a, a), 0.0),
153 (('ixor', a, a), 0),
154 (('inot', ('inot', a)), a),
155 # DeMorgan's Laws
156 (('iand', ('inot', a), ('inot', b)), ('inot', ('ior', a, b))),
157 (('ior', ('inot', a), ('inot', b)), ('inot', ('iand', a, b))),
158 # Shift optimizations
159 (('ishl', 0, a), 0),
160 (('ishl', a, 0), a),
161 (('ishr', 0, a), 0),
162 (('ishr', a, 0), a),
163 (('ushr', 0, a), 0),
164 (('ushr', a, 0), a),
165 # Exponential/logarithmic identities
166 (('fexp2', ('flog2', a)), a), # 2^lg2(a) = a
167 (('flog2', ('fexp2', a)), a), # lg2(2^a) = a
168 (('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
169 (('fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
170 (('fpow', a, 1.0), a),
171 (('fpow', a, 2.0), ('fmul', a, a)),
172 (('fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
173 (('fpow', 2.0, a), ('fexp2', a)),
174 (('fpow', ('fpow', a, 2.2), 0.454545), a),
175 (('fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
176 (('fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
177 (('frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
178 (('frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
179 (('flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
180 (('flog2', ('frcp', a)), ('fneg', ('flog2', a))),
181 (('flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
182 (('flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
183 (('fadd', ('flog2', a), ('flog2', b)), ('flog2', ('fmul', a, b))),
184 (('fadd', ('flog2', a), ('fneg', ('flog2', b))), ('flog2', ('fdiv', a, b))),
185 (('fmul', ('fexp2', a), ('fexp2', b)), ('fexp2', ('fadd', a, b))),
186 # Division and reciprocal
187 (('fdiv', 1.0, a), ('frcp', a)),
188 (('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
189 (('frcp', ('frcp', a)), a),
190 (('frcp', ('fsqrt', a)), ('frsq', a)),
191 (('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
192 (('frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
193 # Boolean simplifications
194 (('ieq', 'a@bool', True), a),
195 (('ine', 'a@bool', True), ('inot', a)),
196 (('ine', 'a@bool', False), a),
197 (('ieq', 'a@bool', False), ('inot', 'a')),
198 (('bcsel', a, True, False), ('ine', a, 0)),
199 (('bcsel', a, False, True), ('ieq', a, 0)),
200 (('bcsel', True, b, c), b),
201 (('bcsel', False, b, c), c),
202 # The result of this should be hit by constant propagation and, in the
203 # next round of opt_algebraic, get picked up by one of the above two.
204 (('bcsel', '#a', b, c), ('bcsel', ('ine', 'a', 0), b, c)),
205
206 (('bcsel', a, b, b), b),
207 (('fcsel', a, b, b), b),
208
209 # Conversions
210 (('i2b', ('b2i', a)), a),
211 (('f2i', ('ftrunc', a)), ('f2i', a)),
212 (('f2u', ('ftrunc', a)), ('f2u', a)),
213
214 # Subtracts
215 (('fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
216 (('isub', a, ('isub', 0, b)), ('iadd', a, b)),
217 (('ussub_4x8', a, 0), a),
218 (('ussub_4x8', a, ~0), 0),
219 (('fsub', a, b), ('fadd', a, ('fneg', b)), 'options->lower_sub'),
220 (('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
221 (('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
222 (('ineg', a), ('isub', 0, a), 'options->lower_negate'),
223 (('fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
224 (('iadd', a, ('isub', 0, b)), ('isub', a, b)),
225 (('fabs', ('fsub', 0.0, a)), ('fabs', a)),
226 (('iabs', ('isub', 0, a)), ('iabs', a)),
227
228 # Misc. lowering
229 (('fmod', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
230 (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
231 (('uadd_carry', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
232 (('usub_borrow', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
233 (('ldexp', 'x', 'exp'),
234 ('fmul', 'x', ('ishl', ('imin', ('imax', ('iadd', 'exp', 0x7f), 0), 0xff), 23))),
235
236 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
237 ('bcsel', ('ilt', 31, 'bits'), 'insert',
238 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
239 'options->lower_bitfield_insert'),
240
241 (('ibitfield_extract', 'value', 'offset', 'bits'),
242 ('bcsel', ('ilt', 31, 'bits'), 'value',
243 ('ibfe', 'value', 'offset', 'bits')),
244 'options->lower_bitfield_extract'),
245
246 (('ubitfield_extract', 'value', 'offset', 'bits'),
247 ('bcsel', ('ult', 31, 'bits'), 'value',
248 ('ubfe', 'value', 'offset', 'bits')),
249 'options->lower_bitfield_extract'),
250
251 (('extract_i8', a, b),
252 ('ishr', ('ishl', a, ('imul', ('isub', 3, b), 8)), 24),
253 'options->lower_extract_byte'),
254
255 (('extract_u8', a, b),
256 ('iand', ('ushr', a, ('imul', b, 8)), 0xff),
257 'options->lower_extract_byte'),
258
259 (('extract_i16', a, b),
260 ('ishr', ('ishl', a, ('imul', ('isub', 1, b), 16)), 16),
261 'options->lower_extract_word'),
262
263 (('extract_u16', a, b),
264 ('iand', ('ushr', a, ('imul', b, 16)), 0xffff),
265 'options->lower_extract_word'),
266
267 (('pack_unorm_2x16', 'v'),
268 ('pack_uvec2_to_uint',
269 ('f2u', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
270 'options->lower_pack_unorm_2x16'),
271
272 (('pack_unorm_4x8', 'v'),
273 ('pack_uvec4_to_uint',
274 ('f2u', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
275 'options->lower_pack_unorm_4x8'),
276
277 (('pack_snorm_2x16', 'v'),
278 ('pack_uvec2_to_uint',
279 ('f2i', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
280 'options->lower_pack_snorm_2x16'),
281
282 (('pack_snorm_4x8', 'v'),
283 ('pack_uvec4_to_uint',
284 ('f2i', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
285 'options->lower_pack_snorm_4x8'),
286
287 (('unpack_unorm_2x16', 'v'),
288 ('fdiv', ('u2f', ('vec2', ('extract_u16', 'v', 0),
289 ('extract_u16', 'v', 1))),
290 65535.0),
291 'options->lower_unpack_unorm_2x16'),
292
293 (('unpack_unorm_4x8', 'v'),
294 ('fdiv', ('u2f', ('vec4', ('extract_u8', 'v', 0),
295 ('extract_u8', 'v', 1),
296 ('extract_u8', 'v', 2),
297 ('extract_u8', 'v', 3))),
298 255.0),
299 'options->lower_unpack_unorm_4x8'),
300
301 (('unpack_snorm_2x16', 'v'),
302 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec2', ('extract_i16', 'v', 0),
303 ('extract_i16', 'v', 1))),
304 32767.0))),
305 'options->lower_unpack_snorm_2x16'),
306
307 (('unpack_snorm_4x8', 'v'),
308 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f', ('vec4', ('extract_i8', 'v', 0),
309 ('extract_i8', 'v', 1),
310 ('extract_i8', 'v', 2),
311 ('extract_i8', 'v', 3))),
312 127.0))),
313 'options->lower_unpack_snorm_4x8'),
314 ]
315
316 # Add optimizations to handle the case where the result of a ternary is
317 # compared to a constant. This way we can take things like
318 #
319 # (a ? 0 : 1) > 0
320 #
321 # and turn it into
322 #
323 # a ? (0 > 0) : (1 > 0)
324 #
325 # which constant folding will eat for lunch. The resulting ternary will
326 # further get cleaned up by the boolean reductions above and we will be
327 # left with just the original variable "a".
328 for op in ['flt', 'fge', 'feq', 'fne',
329 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
330 optimizations += [
331 ((op, ('bcsel', 'a', '#b', '#c'), '#d'),
332 ('bcsel', 'a', (op, 'b', 'd'), (op, 'c', 'd'))),
333 ((op, '#d', ('bcsel', a, '#b', '#c')),
334 ('bcsel', 'a', (op, 'd', 'b'), (op, 'd', 'c'))),
335 ]
336
337 # This section contains "late" optimizations that should be run after the
338 # regular optimizations have finished. Optimizations should go here if
339 # they help code generation but do not necessarily produce code that is
340 # more easily optimizable.
341 late_optimizations = [
342 (('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
343 (('fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
344 (('feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
345 (('fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
346 (('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
347 (('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
348 (('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),
349 (('fdph', a, b), ('fdph_replicated', a, b), 'options->fdot_replicates'),
350 ]
351
352 print nir_algebraic.AlgebraicPass("nir_opt_algebraic", optimizations).render()
353 print nir_algebraic.AlgebraicPass("nir_opt_algebraic_late",
354 late_optimizations).render()