qemu/target/arm/t16.decode

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# Thumb1 instructions
#
# Copyright (c) 2019 Linaro, Ltd
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, see <http://www.gnu.org/licenses/>.
#
# This file is processed by scripts/decodetree.py
#
&empty !extern
&s_rrr_shi !extern s rd rn rm shim shty
&s_rrr_shr !extern s rn rd rm rs shty
&s_rri_rot !extern s rn rd imm rot
&s_rrrr !extern s rd rn rm ra
&rrr_rot !extern rd rn rm rot
&rr !extern rd rm
&ri !extern rd imm
&r !extern rm
&i !extern imm
&ldst_rr !extern p w u rn rt rm shimm shtype
&ldst_ri !extern p w u rn rt imm
&ldst_block !extern rn i b u w list
&setend !extern E
&cps !extern mode imod M A I F
&ci !extern cond imm
# Set S if the instruction is outside of an IT block.
%s !function=t16_setflags
# Data-processing (two low registers)
%reg_0 0:3
@lll_noshr ...... .... rm:3 rd:3 \
&s_rrr_shi %s rn=%reg_0 shim=0 shty=0
@xll_noshr ...... .... rm:3 rn:3 \
&s_rrr_shi s=1 rd=0 shim=0 shty=0
@lxl_shr ...... .... rs:3 rd:3 \
&s_rrr_shr %s rm=%reg_0 rn=0
AND_rrri 010000 0000 ... ... @lll_noshr
EOR_rrri 010000 0001 ... ... @lll_noshr
MOV_rxrr 010000 0010 ... ... @lxl_shr shty=0 # LSL
MOV_rxrr 010000 0011 ... ... @lxl_shr shty=1 # LSR
MOV_rxrr 010000 0100 ... ... @lxl_shr shty=2 # ASR
ADC_rrri 010000 0101 ... ... @lll_noshr
SBC_rrri 010000 0110 ... ... @lll_noshr
MOV_rxrr 010000 0111 ... ... @lxl_shr shty=3 # ROR
TST_xrri 010000 1000 ... ... @xll_noshr
RSB_rri 010000 1001 rn:3 rd:3 &s_rri_rot %s imm=0 rot=0
CMP_xrri 010000 1010 ... ... @xll_noshr
CMN_xrri 010000 1011 ... ... @xll_noshr
ORR_rrri 010000 1100 ... ... @lll_noshr
MUL 010000 1101 rn:3 rd:3 &s_rrrr %s rm=%reg_0 ra=0
BIC_rrri 010000 1110 ... ... @lll_noshr
MVN_rxri 010000 1111 ... ... @lll_noshr
# Load/store (register offset)
@ldst_rr ....... rm:3 rn:3 rt:3 \
&ldst_rr p=1 w=0 u=1 shimm=0 shtype=0
STR_rr 0101 000 ... ... ... @ldst_rr
STRH_rr 0101 001 ... ... ... @ldst_rr
STRB_rr 0101 010 ... ... ... @ldst_rr
LDRSB_rr 0101 011 ... ... ... @ldst_rr
LDR_rr 0101 100 ... ... ... @ldst_rr
LDRH_rr 0101 101 ... ... ... @ldst_rr
LDRB_rr 0101 110 ... ... ... @ldst_rr
LDRSH_rr 0101 111 ... ... ... @ldst_rr
# Load/store word/byte (immediate offset)
%imm5_6x4 6:5 !function=times_4
@ldst_ri_1 ..... imm:5 rn:3 rt:3 \
&ldst_ri p=1 w=0 u=1
@ldst_ri_4 ..... ..... rn:3 rt:3 \
&ldst_ri p=1 w=0 u=1 imm=%imm5_6x4
STR_ri 01100 ..... ... ... @ldst_ri_4
LDR_ri 01101 ..... ... ... @ldst_ri_4
STRB_ri 01110 ..... ... ... @ldst_ri_1
LDRB_ri 01111 ..... ... ... @ldst_ri_1
# Load/store halfword (immediate offset)
%imm5_6x2 6:5 !function=times_2
@ldst_ri_2 ..... ..... rn:3 rt:3 \
&ldst_ri p=1 w=0 u=1 imm=%imm5_6x2
STRH_ri 10000 ..... ... ... @ldst_ri_2
LDRH_ri 10001 ..... ... ... @ldst_ri_2
# Load/store (SP-relative)
%imm8_0x4 0:8 !function=times_4
@ldst_spec_i ..... rt:3 ........ \
&ldst_ri p=1 w=0 u=1 imm=%imm8_0x4
STR_ri 10010 ... ........ @ldst_spec_i rn=13
LDR_ri 10011 ... ........ @ldst_spec_i rn=13
# Load (PC-relative)
LDR_ri 01001 ... ........ @ldst_spec_i rn=15
# Add PC/SP (immediate)
ADR 10100 rd:3 ........ imm=%imm8_0x4
ADD_rri 10101 rd:3 ........ \
&s_rri_rot rn=13 s=0 rot=0 imm=%imm8_0x4 # SP
# Load/store multiple
@ldstm ..... rn:3 list:8 &ldst_block i=1 b=0 u=0 w=1
STM 11000 ... ........ @ldstm
LDM_t16 11001 ... ........ @ldstm
# Shift (immediate)
@shift_i ..... shim:5 rm:3 rd:3 &s_rrr_shi %s rn=%reg_0
MOV_rxri 000 00 ..... ... ... @shift_i shty=0 # LSL
MOV_rxri 000 01 ..... ... ... @shift_i shty=1 # LSR
MOV_rxri 000 10 ..... ... ... @shift_i shty=2 # ASR
# Add/subtract (three low registers)
@addsub_3 ....... rm:3 rn:3 rd:3 \
&s_rrr_shi %s shim=0 shty=0
ADD_rrri 0001100 ... ... ... @addsub_3
SUB_rrri 0001101 ... ... ... @addsub_3
# Add/subtract (two low registers and immediate)
@addsub_2i ....... imm:3 rn:3 rd:3 \
&s_rri_rot %s rot=0
ADD_rri 0001 110 ... ... ... @addsub_2i
SUB_rri 0001 111 ... ... ... @addsub_2i
# Add, subtract, compare, move (one low register and immediate)
%reg_8 8:3
@arith_1i ..... rd:3 imm:8 \
&s_rri_rot rot=0 rn=%reg_8
MOV_rxi 00100 ... ........ @arith_1i %s
CMP_xri 00101 ... ........ @arith_1i s=1
ADD_rri 00110 ... ........ @arith_1i %s
SUB_rri 00111 ... ........ @arith_1i %s
# Add, compare, move (two high registers)
%reg_0_7 7:1 0:3
@addsub_2h .... .... . rm:4 ... \
&s_rrr_shi rd=%reg_0_7 rn=%reg_0_7 shim=0 shty=0
ADD_rrri 0100 0100 . .... ... @addsub_2h s=0
CMP_xrri 0100 0101 . .... ... @addsub_2h s=1
MOV_rxri 0100 0110 . .... ... @addsub_2h s=0
# Adjust SP (immediate)
%imm7_0x4 0:7 !function=times_4
@addsub_sp_i .... .... . ....... \
&s_rri_rot s=0 rd=13 rn=13 rot=0 imm=%imm7_0x4
ADD_rri 1011 0000 0 ....... @addsub_sp_i
SUB_rri 1011 0000 1 ....... @addsub_sp_i
# Branch and exchange
@branchr .... .... . rm:4 ... &r
BX 0100 0111 0 .... 000 @branchr
BLX_r 0100 0111 1 .... 000 @branchr
BXNS 0100 0111 0 .... 100 @branchr
BLXNS 0100 0111 1 .... 100 @branchr
# Extend
@extend .... .... .. rm:3 rd:3 &rrr_rot rn=15 rot=0
SXTAH 1011 0010 00 ... ... @extend
SXTAB 1011 0010 01 ... ... @extend
UXTAH 1011 0010 10 ... ... @extend
UXTAB 1011 0010 11 ... ... @extend
# Change processor state
%imod 4:1 !function=plus_2
SETEND 1011 0110 010 1 E:1 000 &setend
{
CPS 1011 0110 011 . 0 A:1 I:1 F:1 &cps mode=0 M=0 %imod
CPS_v7m 1011 0110 011 im:1 00 I:1 F:1
}
# Reverse bytes
@rdm .... .... .. rm:3 rd:3 &rr
REV 1011 1010 00 ... ... @rdm
REV16 1011 1010 01 ... ... @rdm
REVSH 1011 1010 11 ... ... @rdm
# Hints
{
{
YIELD 1011 1111 0001 0000
WFE 1011 1111 0010 0000
WFI 1011 1111 0011 0000
# TODO: Implement SEV, SEVL; may help SMP performance.
# SEV 1011 1111 0100 0000
# SEVL 1011 1111 0101 0000
# The canonical nop has the second nibble as 0000, but the whole of the
# rest of the space is a reserved hint, behaves as nop.
NOP 1011 1111 ---- 0000
}
IT 1011 1111 cond_mask:8
}
# Miscellaneous 16-bit instructions
%imm6_9_3 9:1 3:5 !function=times_2
HLT 1011 1010 10 imm:6 &i
BKPT 1011 1110 imm:8 &i
CBZ 1011 nz:1 0.1 ..... rn:3 imm=%imm6_9_3
# Push and Pop
%push_list 0:9 !function=t16_push_list
%pop_list 0:9 !function=t16_pop_list
STM 1011 010 ......... \
&ldst_block i=0 b=1 u=0 w=1 rn=13 list=%push_list
LDM_t16 1011 110 ......... \
&ldst_block i=1 b=0 u=0 w=1 rn=13 list=%pop_list
# Conditional branches, Supervisor call
%imm8_0x2 0:s8 !function=times_2
{
UDF 1101 1110 ---- ----
SVC 1101 1111 imm:8 &i
B_cond_thumb 1101 cond:4 ........ &ci imm=%imm8_0x2
}
# Unconditional Branch
%imm11_0x2 0:s11 !function=times_2
B 11100 ........... &i imm=%imm11_0x2
# thumb_insn_is_16bit() ensures we won't be decoding these as
# T16 instructions for a Thumb2 CPU, so these patterns must be
# a Thumb1 split BL/BLX.
BLX_suffix 11101 imm:11 &i
BL_BLX_prefix 11110 imm:s11 &i
BL_suffix 11111 imm:11 &i