qem_m68k : trapcs instruction causes the non-execution of the following 2 instructions
Host environment
- Linux 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt20-1+deb8u2 (2016-01-02) x86_64 GNU/Linux
- QEMU version: (e.g.
qemu-system-x86_64 --version
)qemu-m68k version 6.1.0 (Debian 1:6.1+dfsg-6) Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers
- QEMU command line:
chroot qemu-m68k qemu-m68k-static -cpu m68020 -d in_asm,cpu -D log1.txt ./test
Emulated/Virtualized environment
- Operating system: Debian
- OS/kernel version: (For POSIX guests, use
uname -a
.)Linux kabrousse 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt20-1+deb8u2 (2016-01-02) m68k GNU/Linux
- Architecture: (x86, ARM, s390x, etc.) m68k
Description of problem
In try to run following code :
8004615a: 204f moveal %sp,%a0
8004615c: b1c7 cmpal %d7,%a0
8004615e: 55fc trapcs
80046160: 4e56 0000 linkw %fp,#0
80046164: 2f14 movel %a4@,%sp@-
80046166: 288e movel %fp,%a4@
80046168: c74d exg %a3,%a5
8004616a: 48e7 3030 moveml %d2-%d3/%a2-%a3,%sp@-
8004616e: 7001 moveq #1,%d0
80046170: 3b40 816c movew %d0,%a5@(-32404)
80046174: 7218 moveq #24,%d1
80046176: 3b41 816a movew %d1,%a5@(-32406)
8004617a: 242d 8004 movel %a5@(-32764),%d2
8004617e: 2b42 815c movel %d2,%a5@(-32420)
80046182: 206d 8008 moveal %a5@(-32760),%a0
80046186: 2268 8010 moveal %a0@(-32752),%a1
8004618a: 2b49 8158 movel %a1,%a5@(-32424)
8004618e: 42ad 8154 clrl %a5@(-32428)
80046192: 246d 8154 moveal %a5@(-32428),%a2
80046196: 2b4a 8160 movel %a2,%a5@(-32416)
8004619a: 2b4a 8164 movel %a2,%a5@(-32412)
8004619e: 422d 8168 clrb %a5@(-32408)
800461a2: 7604 moveq #4,%d3
800461a4: 2b43 8150 movel %d3,%a5@(-32432)
800461a8: 2668 8010 moveal %a0@(-32752),%a3
800461ac: 2b4b 814c movel %a3,%a5@(-32436)
800461b0: 2268 8010 moveal %a0@(-32752),%a1
800461b4: 266d 8008 moveal %a5@(-32760),%a3
800461b8: 206b 8008 moveal %a3@(-32760),%a0
800461bc: 4e90 jsr %a0@
800461be: 2b48 8148 movel %a0,%a5@(-32440)
800461c2: 4cdf 0c0c moveml %sp@+,%d2-%d3/%a2-%a3
800461c6: c74d exg %a3,%a5
800461c8: 289f movel %sp@+,%a4@
800461ca: 4e5e unlk %fp
800461cc: 4e75 rts
When I run qemu-m68k -cpu m68020 -d in_asm,cpu, I have :
----------------
IN:
0x8004615a: moveal %sp,%a0
0x8004615c: cmpal %d7,%a0
0x8004615e: trapcs
0x80046160: linkw %fp,#0
0x80046164: movel %a4@,%sp@-
0x80046166: movel %fp,%a4@
0x80046168: exg %a3,%a5
0x8004616a: moveml %d2-%d3/%a2-%a3,%sp@-
0x8004616e: moveq #1,%d0
0x80046170: movew %d0,%a5@(-32404)
0x80046174: moveq #24,%d1
0x80046176: movew %d1,%a5@(-32406)
0x8004617a: movel %a5@(-32764),%d2
0x8004617e: movel %d2,%a5@(-32420)
0x80046182: moveal %a5@(-32760),%a0
0x80046186: moveal %a0@(-32752),%a1
0x8004618a: movel %a1,%a5@(-32424)
0x8004618e: clrl %a5@(-32428)
0x80046192: moveal %a5@(-32428),%a2
0x80046196: movel %a2,%a5@(-32416)
0x8004619a: movel %a2,%a5@(-32412)
0x8004619e: clrb %a5@(-32408)
0x800461a2: moveq #4,%d3
0x800461a4: movel %d3,%a5@(-32432)
0x800461a8: moveal %a0@(-32752),%a3
0x800461ac: movel %a3,%a5@(-32436)
0x800461b0: moveal %a0@(-32752),%a1
0x800461b4: moveal %a5@(-32760),%a3
0x800461b8: moveal %a3@(-32760),%a0
0x800461bc: jsr %a0@
Trace 0: 0x7f83a807e780 [00000000/8004615a/00000000/00000000]
D0 = 00000012 A0 = 8004615a F0 = 7fff ffffffffffffffff ( nan)
D1 = 00000001 A1 = 800466d6 F1 = 7fff ffffffffffffffff ( nan)
D2 = 00000000 A2 = 00000000 F2 = 7fff ffffffffffffffff ( nan)
D3 = 00000000 A3 = 8000c3b0 F3 = 7fff ffffffffffffffff ( nan)
D4 = 00000000 A4 = 8004604c F4 = 7fff ffffffffffffffff ( nan)
D5 = 00000000 A5 = 3ffd7000 F5 = 7fff ffffffffffffffff ( nan)
D6 = 00000004 A6 = 80046038 F6 = 7fff ffffffffffffffff ( nan)
D7 = 80042050 A7 = 80045ff4 F7 = 7fff ffffffffffffffff ( nan)
PC SR = 0004 T:0 I:0 UI --Z--
FPSR = 00000000 ----
FPCR = 0000 X RN
----------------
IN:
0x80046358: lea %a1@(0,%d0:l),%a0
0x8004635c: rts
Trace 0: 0x7f83a807eac0 [00000000/80046358/00000000/00000000]
D0 = 00000001 A0 = 80046358 F0 = 7fff ffffffffffffffff ( nan)
D1 = 00000018 A1 = 00000000 F1 = 7fff ffffffffffffffff ( nan)
D2 = ffffffff A2 = 00000000 F2 = 7fff ffffffffffffffff ( nan)
D3 = 00000004 A3 = 8000c040 F3 = 7fff ffffffffffffffff ( nan)
D4 = 00000000 A4 = 8004604c F4 = 7fff ffffffffffffffff ( nan)
D5 = 00000000 A5 = 8000c3b0 F5 = 7fff ffffffffffffffff ( nan)
D6 = 00000004 A6 = 80046038 F6 = 7fff ffffffffffffffff ( nan)
D7 = 80042050 A7 = 80045fe0 F7 = 7fff ffffffffffffffff ( nan)
PC = 80046358 SR = 0004 T:0 I:0 UI --Z--
FPSR = 00000000 ----
FPCR = 0000 X RN
----------------
Stack pointer is 80045fe0, it should be 80045FD8.
When I run with options -cpu m68020 -d in_asm,cpu,op -singlestep, I have :
----------------
IN:
0x8004615e: trapcs
0x80046160: linkw %fp,#0
Disassembler disagrees with translator over instruction decoding
Please report this to qemu-devel@nongnu.org
OP:
ld_i32 tmp0,env,$0xfffffffffffffff8
brcond_i32 tmp0,$0x0,lt,$L0
---- 8004615e 00000000
mov_i32 tmp0,$0x0
call flush_flags,$0x0,$0,env,CC_OP
setcond_i32 tmp2,CC_C,tmp0,ne
neg_i32 tmp2,tmp2
mov_i32 tmp0,$0x56
mov_i32 PC,$0x80046162
exit_tb $0x0
set_label $L0
exit_tb $0x7fba001a75c3
D0 = 00000012 A0 = 80045ff4 F0 = 7fff ffffffffffffffff ( nan)
D1 = 00000001 A1 = 800466d6 F1 = 7fff ffffffffffffffff ( nan)
D2 = 00000000 A2 = 00000000 F2 = 7fff ffffffffffffffff ( nan)
D3 = 00000000 A3 = 8000c3b0 F3 = 7fff ffffffffffffffff ( nan)
D4 = 00000000 A4 = 8004604c F4 = 7fff ffffffffffffffff ( nan)
D5 = 00000000 A5 = 3ffd5000 F5 = 7fff ffffffffffffffff ( nan)
D6 = 00000004 A6 = 80046038 F6 = 7fff ffffffffffffffff ( nan)
D7 = 80042050 A7 = 80045ff4 F7 = 7fff ffffffffffffffff ( nan)
PC = 8004615e SR = 0000 T:0 I:0 UI -----
FPSR = 00000000 ----
FPCR = 0000 X RN
----------------
IN:
0x80046162: orib #20,%d0
OP:
ld_i32 tmp0,env,$0xfffffffffffffff8
brcond_i32 tmp0,$0x0,lt,$L0
---- 80046162 00000000
mov_i32 tmp0,$0x14
ext8s_i32 tmp3,D0
or_i32 tmp4,tmp3,tmp0
and_i32 D0,D0,$0xffffff00
ext8u_i32 tmp6,tmp4
or_i32 D0,D0,tmp6
ext8s_i32 CC_N,tmp4
discard CC_C
discard CC_Z
discard CC_V
mov_i32 CC_OP,$0xb
mov_i32 PC,$0x80046166
exit_tb $0x0
set_label $L0
exit_tb $0x7fba001a7683
D0 = 00000012 A0 = 80045ff4 F0 = 7fff ffffffffffffffff ( nan)
D1 = 00000001 A1 = 800466d6 F1 = 7fff ffffffffffffffff ( nan)
D2 = 00000000 A2 = 00000000 F2 = 7fff ffffffffffffffff ( nan)
D3 = 00000000 A3 = 8000c3b0 F3 = 7fff ffffffffffffffff ( nan)
D4 = 00000000 A4 = 8004604c F4 = 7fff ffffffffffffffff ( nan)
D5 = 00000000 A5 = 3ffd5000 F5 = 7fff ffffffffffffffff ( nan)
D6 = 00000004 A6 = 80046038 F6 = 7fff ffffffffffffffff ( nan)
D7 = 80042050 A7 = 80045ff4 F7 = 7fff ffffffffffffffff ( nan)
PC = 80046162 SR = 0000 T:0 I:0 UI -----
FPSR = 00000000 ----
FPCR = 0000 X RN
----------------
IN:
0x80046166: movel %fp,%a4@
OP:
ld_i32 tmp0,env,$0xfffffffffffffff8
brcond_i32 tmp0,$0x0,lt,$L0
...
I can see that instructions
0x80046160: linkw %fp,#0
0x80046164: movel %a4@,%sp@-
are not executed and an extra instruction
0x80046162: orib #20,%d0
is executed
Steps to reproduce
Run chroot qemu-m68k qemu-m68k-static -cpu m68020 -d in_asm,cpu -D log1.txt ./test
Additional information
Edited by Frederic LIZOT