xref: /aosp_15_r20/external/mesa3d/src/panfrost/midgard/midgard_nir_algebraic.py (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1#
2# Copyright (C) 2018 Alyssa Rosenzweig
3# Copyright (C) 2019-2020 Collabora, Ltd.
4#
5# Copyright (C) 2016 Intel Corporation
6#
7# Permission is hereby granted, free of charge, to any person obtaining a
8# copy of this software and associated documentation files (the "Software"),
9# to deal in the Software without restriction, including without limitation
10# the rights to use, copy, modify, merge, publish, distribute, sublicense,
11# and/or sell copies of the Software, and to permit persons to whom the
12# Software is furnished to do so, subject to the following conditions:
13#
14# The above copyright notice and this permission notice (including the next
15# paragraph) shall be included in all copies or substantial portions of the
16# Software.
17#
18# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
21# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24# IN THE SOFTWARE.
25
26import argparse
27import sys
28import math
29
30a = 'a'
31b = 'b'
32c = 'c'
33
34algebraic = [
35   # Allows us to schedule as a multiply by 2
36   (('~fadd', ('fadd', a, b), a), ('fadd', ('fadd', a, a), b)),
37
38   # Midgard scales fsin/fcos arguments by pi.
39   (('fsin', a), ('fsin_mdg', ('fdiv', a, math.pi))),
40   (('fcos', a), ('fcos_mdg', ('fdiv', a, math.pi))),
41]
42
43algebraic_late = [
44    # Likewise we want fsub lowered but not isub
45    (('fsub', a, b), ('fadd', a, ('fneg', b))),
46
47    # These two special-cases save space/an op than the actual csel op +
48    # scheduler flexibility
49
50    (('b32csel', a, 'b@32', 0), ('iand', a, b)),
51    (('b32csel', a, 0, 'b@32'), ('iand', ('inot', a), b)),
52
53    # Fuse sat_signed. This should probably be shared with Bifrost
54    (('~fmin', ('fmax', a, -1.0), 1.0), ('fsat_signed_mali', a)),
55    (('~fmax', ('fmin', a, 1.0), -1.0), ('fsat_signed_mali', a)),
56
57    # Fuse clamp_positive. This should probably be shared with Utgard/bifrost
58    (('fmax', a, 0.0), ('fclamp_pos_mali', a)),
59
60    (('ishl', 'a@16', b), ('u2u16', ('ishl', ('u2u32', a), b))),
61    (('ishr', 'a@16', b), ('i2i16', ('ishr', ('i2i32', a), b))),
62    (('ushr', 'a@16', b), ('u2u16', ('ushr', ('u2u32', a), b))),
63
64    (('ishl', 'a@8', b), ('u2u8', ('u2u16', ('ishl', ('u2u32', ('u2u16', a)), b)))),
65    (('ishr', 'a@8', b), ('i2i8', ('i2i16', ('ishr', ('i2i32', ('i2i16', a)), b)))),
66    (('ushr', 'a@8', b), ('u2u8', ('u2u16', ('ushr', ('u2u32', ('u2u16', a)), b)))),
67
68    # Canonical form. The scheduler will convert back if it makes sense.
69    (('fmul', a, 2.0), ('fadd', a, a))
70]
71
72# Size conversion is redundant to Midgard but needed for NIR, and writing this
73# lowering in MIR would be painful without a competent builder, so eat the
74# extra instruction
75for sz in ('8', '16', '32'):
76    converted = ('u2u32', a) if sz != '32' else a
77    algebraic_late += [(('ufind_msb', 'a@' + sz), ('isub', 31, ('uclz', converted)))]
78
79# Midgard is able to type convert down by only one "step" per instruction; if
80# NIR wants more than one step, we need to break up into multiple instructions.
81# Nevertheless, we can do both a size step and a floating/int step at once.
82
83converts = []
84
85for op in ('u2u', 'i2i', 'f2f', 'i2f', 'u2f', 'f2i', 'f2u'):
86    srcsz_max = 64
87    dstsz_max = 64
88    # 8 bit float doesn't exist
89    srcsz_min = 8 if op[0] != 'f' else 16
90    dstsz_min = 8 if op[2] != 'f' else 16
91    dstsz = dstsz_min
92    # Iterate over all possible destination and source sizes
93    while dstsz <= dstsz_max:
94        srcsz = srcsz_min
95        while srcsz <= srcsz_max:
96            # Size converter lowering is only needed if src and dst sizes are
97            # spaced by a factor > 2.
98            if srcsz != dstsz and (srcsz * 2 != dstsz and srcsz != dstsz * 2):
99                cursz = srcsz
100                rule = a
101                # When converting down we first do the type conversion followed
102                # by one or more size conversions. When converting up, we do
103                # the type conversion at the end. This way we don't have to
104                # deal with the fact that f2f8 doesn't exists.
105                sizeconvop = op[0] + '2' + op[0] if srcsz < dstsz else op[2] + '2' + op[2]
106                if srcsz > dstsz and op[0] != op[2]:
107                    rule = (op + str(int(cursz)), rule)
108                while cursz != dstsz:
109                    cursz = cursz / 2 if dstsz < srcsz else cursz * 2
110                    rule = (sizeconvop + str(int(cursz)), rule)
111                if srcsz < dstsz and op[0] != op[2]:
112                    rule = (op + str(int(cursz)), rule)
113                converts += [((op + str(int(dstsz)), 'a@' + str(int(srcsz))), rule)]
114            srcsz *= 2
115        dstsz *= 2
116
117# Try to force constants to the right
118constant_switch = [
119        # fge gets flipped to fle, so we invert to keep the order
120        (('fge', 'a', '#b'), (('inot', ('flt', a, b)))),
121        (('fge32', 'a', '#b'), (('inot', ('flt32', a, b)))),
122        (('ige32', 'a', '#b'), (('inot', ('ilt32', a, b)))),
123        (('uge32', 'a', '#b'), (('inot', ('ult32', a, b)))),
124
125        # fge gets mapped to fle with a flip
126        (('flt32', '#a', 'b'), ('inot', ('fge32', a, b))),
127        (('ilt32', '#a', 'b'), ('inot', ('ige32', a, b))),
128        (('ult32', '#a', 'b'), ('inot', ('uge32', a, b)))
129]
130
131# ..since the above switching happens after algebraic stuff is done
132cancel_inot = [
133        (('inot', ('inot', a)), a),
134        (('b32csel', ('inot', a), b, c), ('b32csel', a, c, b)),
135]
136
137def main():
138    parser = argparse.ArgumentParser()
139    parser.add_argument('-p', '--import-path', required=True)
140    args = parser.parse_args()
141    sys.path.insert(0, args.import_path)
142    run()
143
144
145def run():
146    import nir_algebraic  # pylint: disable=import-error
147
148    print('#include "midgard_nir.h"')
149
150    print(nir_algebraic.AlgebraicPass("midgard_nir_lower_algebraic_early",
151                                      algebraic).render())
152
153    print(nir_algebraic.AlgebraicPass("midgard_nir_lower_algebraic_late",
154                                      algebraic_late + converts + constant_switch).render())
155
156    print(nir_algebraic.AlgebraicPass("midgard_nir_cancel_inot",
157                                      cancel_inot).render())
158
159
160if __name__ == '__main__':
161    main()
162