https://bugs.kde.org/show_bug.cgi?id=360425
Bug ID: 360425
Summary: arm64 unsupported instruction ldpsw
Product: valgrind
Version: unspecified
Platform: Other
OS: Linux
Status: UNCONFIRMED
Severity: normal
Priority: NOR
Component: vex
Assignee: jsew...@acm.org
Reporter: m...@redhat.com
The following program (derived from a gcc test case):
int arr[4][4] = {{0, 1, 1, -1}, {-1, -1, 1, -1}, {1, -1, 1, 1}, {1, -1, -1,
0}};
long long
foo ()
{
long long ll = 0;
ll += arr[1][0];
ll += arr[1][1];
return ll;
}
int main () { return foo () > 0 ? 1 : 0; }
Will compile with gcc 4.8.3 -O2 to:
0000000000400450 <main>:
400450: 90000100 adrp x0, 420000 <_GLOBAL_OFFSET_TABLE_+0x28>
400454: 91008000 add x0, x0, #0x20
400458: b9801001 ldrsw x1, [x0,#16]
40045c: b9801400 ldrsw x0, [x0,#20]
400460: 8b000020 add x0, x1, x0
400464: eb1f001f cmp x0, xzr
400468: 1a9fd7e0 cset w0, gt
40046c: d65f03c0 ret
but with gcc 5.3 -O2 it will generate:
0000000000400420 <main>:
400420: 90000080 adrp x0, 410000 <__FRAME_END__+0xf850>
400424: 9127a000 add x0, x0, #0x9e8
400428: 69420001 ldpsw x1, x0, [x0,#16]
40042c: 8b000020 add x0, x1, x0
400430: eb1f001f cmp x0, xzr
400434: 1a9fd7e0 cset w0, gt
400438: d65f03c0 ret
40043c: d503201f nop
valgrind doesn't recognize te ldpsw instruction:
ARM64 front end: load_store
disInstr(arm64): unhandled instruction 0x69420001
disInstr(arm64): 0110'1001 0100'0010 0000'0000 0000'0001
==17992== valgrind: Unrecognised instruction at address 0x400428.
==17992== at 0x400428: foo (foo.c:7)
==17992== by 0x400428: main (foo.c:12)
==17992== Your program just tried to execute an instruction that Valgrind
==17992== did not recognise. There are two possible reasons for this.
==17992== 1. Your program has a bug and erroneously jumped to a non-code
==17992== location. If you are running Memcheck and you just saw a
==17992== warning about a bad jump, it's probably your program's fault.
==17992== 2. The instruction is legitimate but Valgrind doesn't handle it,
==17992== i.e. it's Valgrind's fault. If you think this is the case or
==17992== you are not sure, please let us know and we'll try to fix it.
==17992== Either way, Valgrind will now raise a SIGILL signal which will
==17992== probably kill your program.
==17992==
==17992== Process terminating with default action of signal 4 (SIGILL)
==17992== Illegal opcode at address 0x400428
==17992== at 0x400428: foo (foo.c:7)
==17992== by 0x400428: main (foo.c:12)
Reproducible: Always
--
You are receiving this mail because:
You are watching all bug changes.
