xref: /openbmc/qemu/target/arm/tcg/a64.decode (revision d2dfe0b5)
1# AArch64 A64 allowed instruction decoding
2#
3#  Copyright (c) 2023 Linaro, Ltd
4#
5# This library is free software; you can redistribute it and/or
6# modify it under the terms of the GNU Lesser General Public
7# License as published by the Free Software Foundation; either
8# version 2.1 of the License, or (at your option) any later version.
9#
10# This library is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13# Lesser General Public License for more details.
14#
15# You should have received a copy of the GNU Lesser General Public
16# License along with this library; if not, see <http://www.gnu.org/licenses/>.
17
18#
19# This file is processed by scripts/decodetree.py
20#
21
22&r               rn
23&ri              rd imm
24&rri_sf          rd rn imm sf
25&i               imm
26
27
28### Data Processing - Immediate
29
30# PC-rel addressing
31
32%imm_pcrel      5:s19 29:2
33@pcrel          . .. ..... ................... rd:5     &ri imm=%imm_pcrel
34
35ADR             0 .. 10000 ................... .....    @pcrel
36ADRP            1 .. 10000 ................... .....    @pcrel
37
38# Add/subtract (immediate)
39
40%imm12_sh12     10:12 !function=shl_12
41@addsub_imm     sf:1 .. ...... . imm:12 rn:5 rd:5
42@addsub_imm12   sf:1 .. ...... . ............ rn:5 rd:5 imm=%imm12_sh12
43
44ADD_i           . 00 100010 0 ............ ..... .....  @addsub_imm
45ADD_i           . 00 100010 1 ............ ..... .....  @addsub_imm12
46ADDS_i          . 01 100010 0 ............ ..... .....  @addsub_imm
47ADDS_i          . 01 100010 1 ............ ..... .....  @addsub_imm12
48
49SUB_i           . 10 100010 0 ............ ..... .....  @addsub_imm
50SUB_i           . 10 100010 1 ............ ..... .....  @addsub_imm12
51SUBS_i          . 11 100010 0 ............ ..... .....  @addsub_imm
52SUBS_i          . 11 100010 1 ............ ..... .....  @addsub_imm12
53
54# Add/subtract (immediate with tags)
55
56&rri_tag        rd rn uimm6 uimm4
57@addsub_imm_tag . .. ...... . uimm6:6 .. uimm4:4 rn:5 rd:5 &rri_tag
58
59ADDG_i          1 00 100011 0 ...... 00 .... ..... ..... @addsub_imm_tag
60SUBG_i          1 10 100011 0 ...... 00 .... ..... ..... @addsub_imm_tag
61
62# Logical (immediate)
63
64&rri_log        rd rn sf dbm
65@logic_imm_64   1 .. ...... dbm:13 rn:5 rd:5            &rri_log sf=1
66@logic_imm_32   0 .. ...... 0 dbm:12 rn:5 rd:5          &rri_log sf=0
67
68AND_i           . 00 100100 . ...... ...... ..... ..... @logic_imm_64
69AND_i           . 00 100100 . ...... ...... ..... ..... @logic_imm_32
70ORR_i           . 01 100100 . ...... ...... ..... ..... @logic_imm_64
71ORR_i           . 01 100100 . ...... ...... ..... ..... @logic_imm_32
72EOR_i           . 10 100100 . ...... ...... ..... ..... @logic_imm_64
73EOR_i           . 10 100100 . ...... ...... ..... ..... @logic_imm_32
74ANDS_i          . 11 100100 . ...... ...... ..... ..... @logic_imm_64
75ANDS_i          . 11 100100 . ...... ...... ..... ..... @logic_imm_32
76
77# Move wide (immediate)
78
79&movw           rd sf imm hw
80@movw_64        1 .. ...... hw:2   imm:16 rd:5          &movw sf=1
81@movw_32        0 .. ...... 0 hw:1 imm:16 rd:5          &movw sf=0
82
83MOVN            . 00 100101 .. ................ .....   @movw_64
84MOVN            . 00 100101 .. ................ .....   @movw_32
85MOVZ            . 10 100101 .. ................ .....   @movw_64
86MOVZ            . 10 100101 .. ................ .....   @movw_32
87MOVK            . 11 100101 .. ................ .....   @movw_64
88MOVK            . 11 100101 .. ................ .....   @movw_32
89
90# Bitfield
91
92&bitfield       rd rn sf immr imms
93@bitfield_64    1 .. ...... 1 immr:6 imms:6 rn:5 rd:5      &bitfield sf=1
94@bitfield_32    0 .. ...... 0 0 immr:5 0 imms:5 rn:5 rd:5  &bitfield sf=0
95
96SBFM            . 00 100110 . ...... ...... ..... ..... @bitfield_64
97SBFM            . 00 100110 . ...... ...... ..... ..... @bitfield_32
98BFM             . 01 100110 . ...... ...... ..... ..... @bitfield_64
99BFM             . 01 100110 . ...... ...... ..... ..... @bitfield_32
100UBFM            . 10 100110 . ...... ...... ..... ..... @bitfield_64
101UBFM            . 10 100110 . ...... ...... ..... ..... @bitfield_32
102
103# Extract
104
105&extract        rd rn rm imm sf
106
107EXTR            1 00 100111 1 0 rm:5 imm:6 rn:5 rd:5     &extract sf=1
108EXTR            0 00 100111 0 0 rm:5 0 imm:5 rn:5 rd:5   &extract sf=0
109
110# Branches
111
112%imm26   0:s26 !function=times_4
113@branch         . ..... .......................... &i imm=%imm26
114
115B               0 00101 .......................... @branch
116BL              1 00101 .......................... @branch
117
118%imm19   5:s19 !function=times_4
119&cbz     rt imm sf nz
120
121CBZ             sf:1 011010 nz:1 ................... rt:5 &cbz imm=%imm19
122
123%imm14     5:s14 !function=times_4
124%imm31_19  31:1 19:5
125&tbz       rt imm nz bitpos
126
127TBZ             . 011011 nz:1 ..... .............. rt:5 &tbz  imm=%imm14 bitpos=%imm31_19
128
129B_cond          0101010 0 ................... 0 cond:4 imm=%imm19
130
131BR              1101011 0000 11111 000000 rn:5 00000 &r
132BLR             1101011 0001 11111 000000 rn:5 00000 &r
133RET             1101011 0010 11111 000000 rn:5 00000 &r
134
135&braz       rn m
136BRAZ            1101011 0000 11111 00001 m:1 rn:5 11111 &braz   # BRAAZ, BRABZ
137BLRAZ           1101011 0001 11111 00001 m:1 rn:5 11111 &braz   # BLRAAZ, BLRABZ
138
139&reta       m
140RETA            1101011 0010 11111 00001 m:1 11111 11111 &reta  # RETAA, RETAB
141
142&bra        rn rm m
143BRA             1101011 1000 11111 00001 m:1 rn:5 rm:5 &bra # BRAA, BRAB
144BLRA            1101011 1001 11111 00001 m:1 rn:5 rm:5 &bra # BLRAA, BLRAB
145
146ERET            1101011 0100 11111 000000 11111 00000
147ERETA           1101011 0100 11111 00001 m:1 11111 11111 &reta  # ERETAA, ERETAB
148
149# We don't need to decode DRPS because it always UNDEFs except when
150# the processor is in halting debug state (which we don't implement).
151# The pattern is listed here as documentation.
152# DRPS            1101011 0101 11111 000000 11111 00000
153