2 # Copyright (C) 2014 Intel Corporation
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:
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
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
24 # Jason Ekstrand (jason@jlekstrand.net)
28 # Convenience variables
34 # Written in the form (<search>, <replace>) where <search> is an expression
35 # and <replace> is either an expression or a value. An expression is
36 # defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
37 # where each source is either an expression or a value. A value can be
38 # either a numeric constant or a string representing a variable name.
40 # If the opcode in a search expression is prefixed by a '~' character, this
41 # indicates that the operation is inexact. Such operations will only get
42 # applied to SSA values that do not have the exact bit set. This should be
43 # used by by any optimizations that are not bit-for-bit exact. It should not,
44 # however, be used for backend-requested lowering operations as those need to
45 # happen regardless of precision.
47 # Variable names are specified as "[#]name[@type][(cond)]" where "#" inicates
48 # that the given variable will only match constants and the type indicates that
49 # the given variable will only match values from ALU instructions with the
50 # given output type, and (cond) specifies an additional condition function
51 # (see nir_search_helpers.h).
53 # For constants, you have to be careful to make sure that it is the right
54 # type because python is unaware of the source and destination types of the
57 # All expression types can have a bit-size specified. For opcodes, this
58 # looks like "op@32", for variables it is "a@32" or "a@uint32" to specify a
59 # type and size, and for literals, you can write "2.0@32". In the search half
60 # of the expression this indicates that it should only match that particular
61 # bit-size. In the replace half of the expression this indicates that the
62 # constructed value should have that bit-size.
66 (('imul', a
, '#b@32(is_pos_power_of_two)'), ('ishl', a
, ('find_lsb', b
))),
67 (('imul', a
, '#b@32(is_neg_power_of_two)'), ('ineg', ('ishl', a
, ('find_lsb', ('iabs', b
))))),
72 (('udiv', a
, '#b@32(is_pos_power_of_two)'), ('ushr', a
, ('find_lsb', b
))),
73 (('idiv', a
, '#b@32(is_pos_power_of_two)'), ('imul', ('isign', a
), ('ushr', ('iabs', a
), ('find_lsb', b
))), 'options->lower_idiv'),
74 (('idiv', a
, '#b@32(is_neg_power_of_two)'), ('ineg', ('imul', ('isign', a
), ('ushr', ('iabs', a
), ('find_lsb', ('iabs', b
))))), 'options->lower_idiv'),
75 (('umod', a
, '#b(is_pos_power_of_two)'), ('iand', a
, ('isub', b
, 1))),
77 (('fneg', ('fneg', a
)), a
),
78 (('ineg', ('ineg', a
)), a
),
79 (('fabs', ('fabs', a
)), ('fabs', a
)),
80 (('fabs', ('fneg', a
)), ('fabs', a
)),
81 (('fabs', ('u2f32', a
)), ('u2f32', a
)),
82 (('iabs', ('iabs', a
)), ('iabs', a
)),
83 (('iabs', ('ineg', a
)), ('iabs', a
)),
84 (('~fadd', a
, 0.0), a
),
86 (('usadd_4x8', a
, 0), a
),
87 (('usadd_4x8', a
, ~
0), ~
0),
88 (('~fadd', ('fmul', a
, b
), ('fmul', a
, c
)), ('fmul', a
, ('fadd', b
, c
))),
89 (('iadd', ('imul', a
, b
), ('imul', a
, c
)), ('imul', a
, ('iadd', b
, c
))),
90 (('~fadd', ('fneg', a
), a
), 0.0),
91 (('iadd', ('ineg', a
), a
), 0),
92 (('iadd', ('ineg', a
), ('iadd', a
, b
)), b
),
93 (('iadd', a
, ('iadd', ('ineg', a
), b
)), b
),
94 (('~fadd', ('fneg', a
), ('fadd', a
, b
)), b
),
95 (('~fadd', a
, ('fadd', ('fneg', a
), b
)), b
),
96 (('~fmul', a
, 0.0), 0.0),
98 (('umul_unorm_4x8', a
, 0), 0),
99 (('umul_unorm_4x8', a
, ~
0), a
),
100 (('fmul', a
, 1.0), a
),
102 (('fmul', a
, -1.0), ('fneg', a
)),
103 (('imul', a
, -1), ('ineg', a
)),
104 (('~ffma', 0.0, a
, b
), b
),
105 (('~ffma', a
, 0.0, b
), b
),
106 (('~ffma', a
, b
, 0.0), ('fmul', a
, b
)),
107 (('ffma', a
, 1.0, b
), ('fadd', a
, b
)),
108 (('ffma', 1.0, a
, b
), ('fadd', a
, b
)),
109 (('~flrp', a
, b
, 0.0), a
),
110 (('~flrp', a
, b
, 1.0), b
),
111 (('~flrp', a
, a
, b
), a
),
112 (('~flrp', 0.0, a
, b
), ('fmul', a
, b
)),
113 (('~flrp', a
, b
, ('b2f', c
)), ('bcsel', c
, b
, a
), 'options->lower_flrp32'),
114 (('~flrp', a
, 0.0, c
), ('fadd', ('fmul', ('fneg', a
), c
), a
)),
115 (('flrp@32', a
, b
, c
), ('fadd', ('fmul', c
, ('fsub', b
, a
)), a
), 'options->lower_flrp32'),
116 (('flrp@64', a
, b
, c
), ('fadd', ('fmul', c
, ('fsub', b
, a
)), a
), 'options->lower_flrp64'),
117 (('ffract', a
), ('fsub', a
, ('ffloor', a
)), 'options->lower_ffract'),
118 (('~fadd', ('fmul', a
, ('fadd', 1.0, ('fneg', ('b2f', c
)))), ('fmul', b
, ('b2f', c
))), ('bcsel', c
, b
, a
), 'options->lower_flrp32'),
119 (('~fadd@32', ('fmul', a
, ('fadd', 1.0, ('fneg', c
))), ('fmul', b
, c
)), ('flrp', a
, b
, c
), '!options->lower_flrp32'),
120 (('~fadd@64', ('fmul', a
, ('fadd', 1.0, ('fneg', c
))), ('fmul', b
, c
)), ('flrp', a
, b
, c
), '!options->lower_flrp64'),
121 (('~fadd', a
, ('fmul', ('b2f', c
), ('fadd', b
, ('fneg', a
)))), ('bcsel', c
, b
, a
), 'options->lower_flrp32'),
122 (('~fadd@32', a
, ('fmul', c
, ('fadd', b
, ('fneg', a
)))), ('flrp', a
, b
, c
), '!options->lower_flrp32'),
123 (('~fadd@64', a
, ('fmul', c
, ('fadd', b
, ('fneg', a
)))), ('flrp', a
, b
, c
), '!options->lower_flrp64'),
124 (('ffma', a
, b
, c
), ('fadd', ('fmul', a
, b
), c
), 'options->lower_ffma'),
125 (('~fadd', ('fmul', a
, b
), c
), ('ffma', a
, b
, c
), 'options->fuse_ffma'),
127 # (a * #b + #c) << #d
128 # ((a * #b) << #d) + (#c << #d)
129 # (a * (#b << #d)) + (#c << #d)
130 (('ishl', ('iadd', ('imul', a
, '#b'), '#c'), '#d'),
131 ('iadd', ('imul', a
, ('ishl', b
, d
)), ('ishl', c
, d
))),
135 (('ishl', ('imul', a
, '#b'), '#c'), ('imul', a
, ('ishl', b
, c
))),
137 # Comparison simplifications
138 (('~inot', ('flt', a
, b
)), ('fge', a
, b
)),
139 (('~inot', ('fge', a
, b
)), ('flt', a
, b
)),
140 (('~inot', ('feq', a
, b
)), ('fne', a
, b
)),
141 (('~inot', ('fne', a
, b
)), ('feq', a
, b
)),
142 (('inot', ('ilt', a
, b
)), ('ige', a
, b
)),
143 (('inot', ('ige', a
, b
)), ('ilt', a
, b
)),
144 (('inot', ('ieq', a
, b
)), ('ine', a
, b
)),
145 (('inot', ('ine', a
, b
)), ('ieq', a
, b
)),
149 # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
151 (('fge', 0.0, ('b2f', a
)), ('inot', a
)),
153 (('fge', ('fneg', ('b2f', a
)), 0.0), ('inot', a
)),
157 # fabs(a) != 0.0 because fabs(a) must be >= 0
159 (('flt', 0.0, ('fabs', a
)), ('fne', a
, 0.0)),
161 # ignore this opt when the result is used by a bcsel or if so we can make
162 # use of conditional modifiers on supported hardware.
163 (('flt(is_not_used_by_conditional)', ('fadd(is_used_once)', a
, ('fneg', b
)), 0.0), ('flt', a
, b
)),
165 (('fge', ('fneg', ('fabs', a
)), 0.0), ('feq', a
, 0.0)),
166 (('bcsel', ('flt', b
, a
), b
, a
), ('fmin', a
, b
)),
167 (('bcsel', ('flt', a
, b
), b
, a
), ('fmax', a
, b
)),
168 (('bcsel', ('inot', a
), b
, c
), ('bcsel', a
, c
, b
)),
169 (('bcsel', a
, ('bcsel', a
, b
, c
), d
), ('bcsel', a
, b
, d
)),
170 (('bcsel', a
, True, 'b@bool'), ('ior', a
, b
)),
177 (('fmin', a
, ('fneg', a
)), ('fneg', ('fabs', a
))),
178 (('imin', a
, ('ineg', a
)), ('ineg', ('iabs', a
))),
179 (('fmin', a
, ('fneg', ('fabs', a
))), ('fneg', ('fabs', a
))),
180 (('imin', a
, ('ineg', ('iabs', a
))), ('ineg', ('iabs', a
))),
181 (('fmin', a
, ('fabs', a
)), a
),
182 (('imin', a
, ('iabs', a
)), a
),
183 (('fmax', a
, ('fneg', ('fabs', a
))), a
),
184 (('imax', a
, ('ineg', ('iabs', a
))), a
),
185 (('fmax', a
, ('fabs', a
)), ('fabs', a
)),
186 (('imax', a
, ('iabs', a
)), ('iabs', a
)),
187 (('fmax', a
, ('fneg', a
)), ('fabs', a
)),
188 (('imax', a
, ('ineg', a
)), ('iabs', a
)),
189 (('~fmin', ('fmax', a
, 0.0), 1.0), ('fsat', a
), '!options->lower_fsat'),
190 (('~fmax', ('fmin', a
, 1.0), 0.0), ('fsat', a
), '!options->lower_fsat'),
191 (('fsat', a
), ('fmin', ('fmax', a
, 0.0), 1.0), 'options->lower_fsat'),
192 (('fsat', ('fsat', a
)), ('fsat', a
)),
193 (('fmin', ('fmax', ('fmin', ('fmax', a
, b
), c
), b
), c
), ('fmin', ('fmax', a
, b
), c
)),
194 (('imin', ('imax', ('imin', ('imax', a
, b
), c
), b
), c
), ('imin', ('imax', a
, b
), c
)),
195 (('umin', ('umax', ('umin', ('umax', a
, b
), c
), b
), c
), ('umin', ('umax', a
, b
), c
)),
196 (('fmax', ('fsat', a
), '#b@32(is_zero_to_one)'), ('fsat', ('fmax', a
, b
))),
197 (('fmin', ('fsat', a
), '#b@32(is_zero_to_one)'), ('fsat', ('fmin', a
, b
))),
198 (('extract_u8', ('imin', ('imax', a
, 0), 0xff), 0), ('imin', ('imax', a
, 0), 0xff)),
199 (('~ior', ('flt', a
, b
), ('flt', a
, c
)), ('flt', a
, ('fmax', b
, c
))),
200 (('~ior', ('flt', a
, c
), ('flt', b
, c
)), ('flt', ('fmin', a
, b
), c
)),
201 (('~ior', ('fge', a
, b
), ('fge', a
, c
)), ('fge', a
, ('fmin', b
, c
))),
202 (('~ior', ('fge', a
, c
), ('fge', b
, c
)), ('fge', ('fmax', a
, b
), c
)),
203 (('fabs', ('slt', a
, b
)), ('slt', a
, b
)),
204 (('fabs', ('sge', a
, b
)), ('sge', a
, b
)),
205 (('fabs', ('seq', a
, b
)), ('seq', a
, b
)),
206 (('fabs', ('sne', a
, b
)), ('sne', a
, b
)),
207 (('slt', a
, b
), ('b2f', ('flt', a
, b
)), 'options->lower_scmp'),
208 (('sge', a
, b
), ('b2f', ('fge', a
, b
)), 'options->lower_scmp'),
209 (('seq', a
, b
), ('b2f', ('feq', a
, b
)), 'options->lower_scmp'),
210 (('sne', a
, b
), ('b2f', ('fne', a
, b
)), 'options->lower_scmp'),
211 (('fne', ('fneg', a
), a
), ('fne', a
, 0.0)),
212 (('feq', ('fneg', a
), a
), ('feq', a
, 0.0)),
214 (('imul', ('b2i', a
), ('b2i', b
)), ('b2i', ('iand', a
, b
))),
215 (('fmul', ('b2f', a
), ('b2f', b
)), ('b2f', ('iand', a
, b
))),
216 (('fsat', ('fadd', ('b2f', a
), ('b2f', b
))), ('b2f', ('ior', a
, b
))),
217 (('iand', 'a@bool', 1.0), ('b2f', a
)),
218 # True/False are ~0 and 0 in NIR. b2i of True is 1, and -1 is ~0 (True).
219 (('ineg', ('b2i@32', a
)), a
),
220 (('flt', ('fneg', ('b2f', a
)), 0), a
), # Generated by TGSI KILL_IF.
221 (('flt', ('fsub', 0.0, ('b2f', a
)), 0), a
), # Generated by TGSI KILL_IF.
222 # Comparison with the same args. Note that these are not done for
223 # the float versions because NaN always returns false on float
225 (('ilt', a
, a
), False),
226 (('ige', a
, a
), True),
227 (('ieq', a
, a
), True),
228 (('ine', a
, a
), False),
229 (('ult', a
, a
), False),
230 (('uge', a
, a
), True),
231 # Logical and bit operations
232 (('fand', a
, 0.0), 0.0),
234 (('iand', a
, ~
0), a
),
238 (('ior', a
, True), True),
239 (('fxor', a
, a
), 0.0),
242 (('inot', ('inot', a
)), a
),
244 (('iand', ('inot', a
), ('inot', b
)), ('inot', ('ior', a
, b
))),
245 (('ior', ('inot', a
), ('inot', b
)), ('inot', ('iand', a
, b
))),
246 # Shift optimizations
253 (('iand', 0xff, ('ushr@32', a
, 24)), ('ushr', a
, 24)),
254 (('iand', 0xffff, ('ushr@32', a
, 16)), ('ushr', a
, 16)),
255 # Exponential/logarithmic identities
256 (('~fexp2', ('flog2', a
)), a
), # 2^lg2(a) = a
257 (('~flog2', ('fexp2', a
)), a
), # lg2(2^a) = a
258 (('fpow', a
, b
), ('fexp2', ('fmul', ('flog2', a
), b
)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
259 (('~fexp2', ('fmul', ('flog2', a
), b
)), ('fpow', a
, b
), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
260 (('~fexp2', ('fadd', ('fmul', ('flog2', a
), b
), ('fmul', ('flog2', c
), d
))),
261 ('~fmul', ('fpow', a
, b
), ('fpow', c
, d
)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
262 (('~fpow', a
, 1.0), a
),
263 (('~fpow', a
, 2.0), ('fmul', a
, a
)),
264 (('~fpow', a
, 4.0), ('fmul', ('fmul', a
, a
), ('fmul', a
, a
))),
265 (('~fpow', 2.0, a
), ('fexp2', a
)),
266 (('~fpow', ('fpow', a
, 2.2), 0.454545), a
),
267 (('~fpow', ('fabs', ('fpow', a
, 2.2)), 0.454545), ('fabs', a
)),
268 (('~fsqrt', ('fexp2', a
)), ('fexp2', ('fmul', 0.5, a
))),
269 (('~frcp', ('fexp2', a
)), ('fexp2', ('fneg', a
))),
270 (('~frsq', ('fexp2', a
)), ('fexp2', ('fmul', -0.5, a
))),
271 (('~flog2', ('fsqrt', a
)), ('fmul', 0.5, ('flog2', a
))),
272 (('~flog2', ('frcp', a
)), ('fneg', ('flog2', a
))),
273 (('~flog2', ('frsq', a
)), ('fmul', -0.5, ('flog2', a
))),
274 (('~flog2', ('fpow', a
, b
)), ('fmul', b
, ('flog2', a
))),
275 (('~fmul', ('fexp2', a
), ('fexp2', b
)), ('fexp2', ('fadd', a
, b
))),
276 # Division and reciprocal
277 (('~fdiv', 1.0, a
), ('frcp', a
)),
278 (('fdiv', a
, b
), ('fmul', a
, ('frcp', b
)), 'options->lower_fdiv'),
279 (('~frcp', ('frcp', a
)), a
),
280 (('~frcp', ('fsqrt', a
)), ('frsq', a
)),
281 (('fsqrt', a
), ('frcp', ('frsq', a
)), 'options->lower_fsqrt'),
282 (('~frcp', ('frsq', a
)), ('fsqrt', a
), '!options->lower_fsqrt'),
283 # Boolean simplifications
284 (('ieq', 'a@bool', True), a
),
285 (('ine(is_not_used_by_if)', 'a@bool', True), ('inot', a
)),
286 (('ine', 'a@bool', False), a
),
287 (('ieq(is_not_used_by_if)', 'a@bool', False), ('inot', 'a')),
288 (('bcsel', a
, True, False), a
),
289 (('bcsel', a
, False, True), ('inot', a
)),
290 (('bcsel@32', a
, 1.0, 0.0), ('b2f', a
)),
291 (('bcsel@32', a
, 0.0, 1.0), ('b2f', ('inot', a
))),
292 (('bcsel@32', a
, -1.0, -0.0), ('fneg', ('b2f', a
))),
293 (('bcsel@32', a
, -0.0, -1.0), ('fneg', ('b2f', ('inot', a
)))),
294 (('bcsel', True, b
, c
), b
),
295 (('bcsel', False, b
, c
), c
),
296 # The result of this should be hit by constant propagation and, in the
297 # next round of opt_algebraic, get picked up by one of the above two.
298 (('bcsel', '#a', b
, c
), ('bcsel', ('ine', 'a', 0), b
, c
)),
300 (('bcsel', a
, b
, b
), b
),
301 (('fcsel', a
, b
, b
), b
),
304 (('i2b', ('b2i', a
)), a
),
305 (('f2i32', ('ftrunc', a
)), ('f2i32', a
)),
306 (('f2u32', ('ftrunc', a
)), ('f2u32', a
)),
307 (('i2b', ('ineg', a
)), ('i2b', a
)),
308 (('i2b', ('iabs', a
)), ('i2b', a
)),
309 (('fabs', ('b2f', a
)), ('b2f', a
)),
310 (('iabs', ('b2i', a
)), ('b2i', a
)),
312 # Packing and then unpacking does nothing
313 (('unpack_64_2x32_split_x', ('pack_64_2x32_split', a
, b
)), a
),
314 (('unpack_64_2x32_split_y', ('pack_64_2x32_split', a
, b
)), b
),
315 (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a
),
316 ('unpack_64_2x32_split_y', a
)), a
),
319 (('ushr', a
, 24), ('extract_u8', a
, 3), '!options->lower_extract_byte'),
320 (('iand', 0xff, ('ushr', a
, 16)), ('extract_u8', a
, 2), '!options->lower_extract_byte'),
321 (('iand', 0xff, ('ushr', a
, 8)), ('extract_u8', a
, 1), '!options->lower_extract_byte'),
322 (('iand', 0xff, a
), ('extract_u8', a
, 0), '!options->lower_extract_byte'),
325 (('ushr', a
, 16), ('extract_u16', a
, 1), '!options->lower_extract_word'),
326 (('iand', 0xffff, a
), ('extract_u16', a
, 0), '!options->lower_extract_word'),
329 (('~fsub', a
, ('fsub', 0.0, b
)), ('fadd', a
, b
)),
330 (('isub', a
, ('isub', 0, b
)), ('iadd', a
, b
)),
331 (('ussub_4x8', a
, 0), a
),
332 (('ussub_4x8', a
, ~
0), 0),
333 (('fsub', a
, b
), ('fadd', a
, ('fneg', b
)), 'options->lower_sub'),
334 (('isub', a
, b
), ('iadd', a
, ('ineg', b
)), 'options->lower_sub'),
335 (('fneg', a
), ('fsub', 0.0, a
), 'options->lower_negate'),
336 (('ineg', a
), ('isub', 0, a
), 'options->lower_negate'),
337 (('~fadd', a
, ('fsub', 0.0, b
)), ('fsub', a
, b
)),
338 (('iadd', a
, ('isub', 0, b
)), ('isub', a
, b
)),
339 (('fabs', ('fsub', 0.0, a
)), ('fabs', a
)),
340 (('iabs', ('isub', 0, a
)), ('iabs', a
)),
342 # Propagate negation up multiplication chains
343 (('fmul', ('fneg', a
), b
), ('fneg', ('fmul', a
, b
))),
344 (('imul', ('ineg', a
), b
), ('ineg', ('imul', a
, b
))),
346 # Propagate constants up multiplication chains
347 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fmul', ('fmul', a
, c
), b
)),
348 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('imul', ('imul', a
, c
), b
)),
349 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('fadd', ('fadd', a
, c
), b
)),
350 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', 'b(is_not_const)'), '#c'), ('iadd', ('iadd', a
, c
), b
)),
352 # Reassociate constants in add/mul chains so they can be folded together.
353 # For now, we mostly only handle cases where the constants are separated by
354 # a single non-constant. We could do better eventually.
355 (('~fmul', '#a', ('fmul', b
, '#c')), ('fmul', ('fmul', a
, c
), b
)),
356 (('imul', '#a', ('imul', b
, '#c')), ('imul', ('imul', a
, c
), b
)),
357 (('~fadd', '#a', ('fadd', b
, '#c')), ('fadd', ('fadd', a
, c
), b
)),
358 (('iadd', '#a', ('iadd', b
, '#c')), ('iadd', ('iadd', a
, c
), b
)),
361 (('bcsel', ('ige', ('find_lsb', a
), 0), ('find_lsb', a
), -1), ('find_lsb', a
)),
362 (('bcsel', ('ige', ('ifind_msb', a
), 0), ('ifind_msb', a
), -1), ('ifind_msb', a
)),
363 (('bcsel', ('ige', ('ufind_msb', a
), 0), ('ufind_msb', a
), -1), ('ufind_msb', a
)),
365 (('bcsel', ('ine', a
, 0), ('find_lsb', a
), -1), ('find_lsb', a
)),
366 (('bcsel', ('ine', a
, 0), ('ifind_msb', a
), -1), ('ifind_msb', a
)),
367 (('bcsel', ('ine', a
, 0), ('ufind_msb', a
), -1), ('ufind_msb', a
)),
369 (('bcsel', ('ine', a
, -1), ('ifind_msb', a
), -1), ('ifind_msb', a
)),
372 (('fmod@32', a
, b
), ('fsub', a
, ('fmul', b
, ('ffloor', ('fdiv', a
, b
)))), 'options->lower_fmod32'),
373 (('fmod@64', a
, b
), ('fsub', a
, ('fmul', b
, ('ffloor', ('fdiv', a
, b
)))), 'options->lower_fmod64'),
374 (('frem', a
, b
), ('fsub', a
, ('fmul', b
, ('ftrunc', ('fdiv', a
, b
)))), 'options->lower_fmod32'),
375 (('uadd_carry@32', a
, b
), ('b2i', ('ult', ('iadd', a
, b
), a
)), 'options->lower_uadd_carry'),
376 (('usub_borrow@32', a
, b
), ('b2i', ('ult', a
, b
)), 'options->lower_usub_borrow'),
378 (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
379 ('bcsel', ('ilt', 31, 'bits'), 'insert',
380 ('bfi', ('bfm', 'bits', 'offset'), 'insert', 'base')),
381 'options->lower_bitfield_insert'),
383 (('ibitfield_extract', 'value', 'offset', 'bits'),
384 ('bcsel', ('ilt', 31, 'bits'), 'value',
385 ('ibfe', 'value', 'offset', 'bits')),
386 'options->lower_bitfield_extract'),
388 (('ubitfield_extract', 'value', 'offset', 'bits'),
389 ('bcsel', ('ult', 31, 'bits'), 'value',
390 ('ubfe', 'value', 'offset', 'bits')),
391 'options->lower_bitfield_extract'),
393 (('extract_i8', a
, 'b@32'),
394 ('ishr', ('ishl', a
, ('imul', ('isub', 3, b
), 8)), 24),
395 'options->lower_extract_byte'),
397 (('extract_u8', a
, 'b@32'),
398 ('iand', ('ushr', a
, ('imul', b
, 8)), 0xff),
399 'options->lower_extract_byte'),
401 (('extract_i16', a
, 'b@32'),
402 ('ishr', ('ishl', a
, ('imul', ('isub', 1, b
), 16)), 16),
403 'options->lower_extract_word'),
405 (('extract_u16', a
, 'b@32'),
406 ('iand', ('ushr', a
, ('imul', b
, 16)), 0xffff),
407 'options->lower_extract_word'),
409 (('pack_unorm_2x16', 'v'),
410 ('pack_uvec2_to_uint',
411 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 65535.0)))),
412 'options->lower_pack_unorm_2x16'),
414 (('pack_unorm_4x8', 'v'),
415 ('pack_uvec4_to_uint',
416 ('f2u32', ('fround_even', ('fmul', ('fsat', 'v'), 255.0)))),
417 'options->lower_pack_unorm_4x8'),
419 (('pack_snorm_2x16', 'v'),
420 ('pack_uvec2_to_uint',
421 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 32767.0)))),
422 'options->lower_pack_snorm_2x16'),
424 (('pack_snorm_4x8', 'v'),
425 ('pack_uvec4_to_uint',
426 ('f2i32', ('fround_even', ('fmul', ('fmin', 1.0, ('fmax', -1.0, 'v')), 127.0)))),
427 'options->lower_pack_snorm_4x8'),
429 (('unpack_unorm_2x16', 'v'),
430 ('fdiv', ('u2f32', ('vec2', ('extract_u16', 'v', 0),
431 ('extract_u16', 'v', 1))),
433 'options->lower_unpack_unorm_2x16'),
435 (('unpack_unorm_4x8', 'v'),
436 ('fdiv', ('u2f32', ('vec4', ('extract_u8', 'v', 0),
437 ('extract_u8', 'v', 1),
438 ('extract_u8', 'v', 2),
439 ('extract_u8', 'v', 3))),
441 'options->lower_unpack_unorm_4x8'),
443 (('unpack_snorm_2x16', 'v'),
444 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f32', ('vec2', ('extract_i16', 'v', 0),
445 ('extract_i16', 'v', 1))),
447 'options->lower_unpack_snorm_2x16'),
449 (('unpack_snorm_4x8', 'v'),
450 ('fmin', 1.0, ('fmax', -1.0, ('fdiv', ('i2f32', ('vec4', ('extract_i8', 'v', 0),
451 ('extract_i8', 'v', 1),
452 ('extract_i8', 'v', 2),
453 ('extract_i8', 'v', 3))),
455 'options->lower_unpack_snorm_4x8'),
458 def fexp2i(exp
, bits
):
459 # We assume that exp is already in the right range.
461 return ('ishl', ('iadd', exp
, 127), 23)
463 return ('pack_64_2x32_split', 0, ('ishl', ('iadd', exp
, 1023), 20))
467 def ldexp(f
, exp
, bits
):
468 # First, we clamp exp to a reasonable range. The maximum possible range
469 # for a normal exponent is [-126, 127] and, throwing in denormals, you get
470 # a maximum range of [-149, 127]. This means that we can potentially have
471 # a swing of +-276. If you start with FLT_MAX, you actually have to do
472 # ldexp(FLT_MAX, -278) to get it to flush all the way to zero. The GLSL
473 # spec, on the other hand, only requires that we handle an exponent value
474 # in the range [-126, 128]. This implementation is *mostly* correct; it
475 # handles a range on exp of [-252, 254] which allows you to create any
476 # value (including denorms if the hardware supports it) and to adjust the
477 # exponent of any normal value to anything you want.
479 exp
= ('imin', ('imax', exp
, -252), 254)
481 exp
= ('imin', ('imax', exp
, -2044), 2046)
485 # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2.
486 # (We use ishr which isn't the same for -1, but the -1 case still works
487 # since we use exp-exp/2 as the second exponent.) While the spec
488 # technically defines ldexp as f * 2.0^exp, simply multiplying once doesn't
489 # work with denormals and doesn't allow for the full swing in exponents
490 # that you can get with normalized values. Instead, we create two powers
491 # of two and multiply by them each in turn. That way the effective range
492 # of our exponent is doubled.
493 pow2_1
= fexp2i(('ishr', exp
, 1), bits
)
494 pow2_2
= fexp2i(('isub', exp
, ('ishr', exp
, 1)), bits
)
495 return ('fmul', ('fmul', f
, pow2_1
), pow2_2
)
498 (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32)),
499 (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64)),
502 # Unreal Engine 4 demo applications open-codes bitfieldReverse()
503 def bitfield_reverse(u
):
504 step1
= ('ior', ('ishl', u
, 16), ('ushr', u
, 16))
505 step2
= ('ior', ('ishl', ('iand', step1
, 0x00ff00ff), 8), ('ushr', ('iand', step1
, 0xff00ff00), 8))
506 step3
= ('ior', ('ishl', ('iand', step2
, 0x0f0f0f0f), 4), ('ushr', ('iand', step2
, 0xf0f0f0f0), 4))
507 step4
= ('ior', ('ishl', ('iand', step3
, 0x33333333), 2), ('ushr', ('iand', step3
, 0xcccccccc), 2))
508 step5
= ('ior', ('ishl', ('iand', step4
, 0x55555555), 1), ('ushr', ('iand', step4
, 0xaaaaaaaa), 1))
512 optimizations
+= [(bitfield_reverse('x@32'), ('bitfield_reverse', 'x'))]
514 # For any float comparison operation, "cmp", if you have "a == a && a cmp b"
515 # then the "a == a" is redundant because it's equivalent to "a is not NaN"
516 # and, if a is a NaN then the second comparison will fail anyway.
517 for op
in ['flt', 'fge', 'feq']:
519 (('iand', ('feq', a
, a
), (op
, a
, b
)), (op
, a
, b
)),
520 (('iand', ('feq', a
, a
), (op
, b
, a
)), (op
, b
, a
)),
523 # Add optimizations to handle the case where the result of a ternary is
524 # compared to a constant. This way we can take things like
530 # a ? (0 > 0) : (1 > 0)
532 # which constant folding will eat for lunch. The resulting ternary will
533 # further get cleaned up by the boolean reductions above and we will be
534 # left with just the original variable "a".
535 for op
in ['flt', 'fge', 'feq', 'fne',
536 'ilt', 'ige', 'ieq', 'ine', 'ult', 'uge']:
538 ((op
, ('bcsel', 'a', '#b', '#c'), '#d'),
539 ('bcsel', 'a', (op
, 'b', 'd'), (op
, 'c', 'd'))),
540 ((op
, '#d', ('bcsel', a
, '#b', '#c')),
541 ('bcsel', 'a', (op
, 'd', 'b'), (op
, 'd', 'c'))),
544 # This section contains "late" optimizations that should be run before
545 # creating ffmas and calling regular optimizations for the final time.
546 # Optimizations should go here if they help code generation and conflict
547 # with the regular optimizations.
548 before_ffma_optimizations
= [
549 # Propagate constants down multiplication chains
550 (('~fmul(is_used_once)', ('fmul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fmul', ('fmul', a
, c
), b
)),
551 (('imul(is_used_once)', ('imul(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('imul', ('imul', a
, c
), b
)),
552 (('~fadd(is_used_once)', ('fadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('fadd', ('fadd', a
, c
), b
)),
553 (('iadd(is_used_once)', ('iadd(is_used_once)', 'a(is_not_const)', '#b'), 'c(is_not_const)'), ('iadd', ('iadd', a
, c
), b
)),
555 (('~fadd', ('fmul', a
, b
), ('fmul', a
, c
)), ('fmul', a
, ('fadd', b
, c
))),
556 (('iadd', ('imul', a
, b
), ('imul', a
, c
)), ('imul', a
, ('iadd', b
, c
))),
557 (('~fadd', ('fneg', a
), a
), 0.0),
558 (('iadd', ('ineg', a
), a
), 0),
559 (('iadd', ('ineg', a
), ('iadd', a
, b
)), b
),
560 (('iadd', a
, ('iadd', ('ineg', a
), b
)), b
),
561 (('~fadd', ('fneg', a
), ('fadd', a
, b
)), b
),
562 (('~fadd', a
, ('fadd', ('fneg', a
), b
)), b
),
565 # This section contains "late" optimizations that should be run after the
566 # regular optimizations have finished. Optimizations should go here if
567 # they help code generation but do not necessarily produce code that is
568 # more easily optimizable.
569 late_optimizations
= [
570 # Most of these optimizations aren't quite safe when you get infinity or
571 # Nan involved but the first one should be fine.
572 (('flt', ('fadd', a
, b
), 0.0), ('flt', a
, ('fneg', b
))),
573 (('~fge', ('fadd', a
, b
), 0.0), ('fge', a
, ('fneg', b
))),
574 (('~feq', ('fadd', a
, b
), 0.0), ('feq', a
, ('fneg', b
))),
575 (('~fne', ('fadd', a
, b
), 0.0), ('fne', a
, ('fneg', b
))),
577 (('fdot2', a
, b
), ('fdot_replicated2', a
, b
), 'options->fdot_replicates'),
578 (('fdot3', a
, b
), ('fdot_replicated3', a
, b
), 'options->fdot_replicates'),
579 (('fdot4', a
, b
), ('fdot_replicated4', a
, b
), 'options->fdot_replicates'),
580 (('fdph', a
, b
), ('fdph_replicated', a
, b
), 'options->fdot_replicates'),
582 (('b2f(is_used_more_than_once)', ('inot', a
)), ('bcsel', a
, 0.0, 1.0)),
583 (('fneg(is_used_more_than_once)', ('b2f', ('inot', a
))), ('bcsel', a
, -0.0, -1.0)),
585 # we do these late so that we don't get in the way of creating ffmas
586 (('fmin', ('fadd(is_used_once)', '#c', a
), ('fadd(is_used_once)', '#c', b
)), ('fadd', c
, ('fmin', a
, b
))),
587 (('fmax', ('fadd(is_used_once)', '#c', a
), ('fadd(is_used_once)', '#c', b
)), ('fadd', c
, ('fmax', a
, b
))),
590 print nir_algebraic
.AlgebraicPass("nir_opt_algebraic", optimizations
).render()
591 print nir_algebraic
.AlgebraicPass("nir_opt_algebraic_before_ffma",
592 before_ffma_optimizations
).render()
593 print nir_algebraic
.AlgebraicPass("nir_opt_algebraic_late",
594 late_optimizations
).render()