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Take the following program:
// gcc -g -Wall -mrtm -o rtm-test rtm-test.c
#include <immintrin.h>
#include <stdio.h>
int
main (int argc, char **argv)
{
unsigned status;
if ((status = _xbegin ()) == _XBEGIN_STARTED)
{
// Note that under valgrind the transaction will never start.
// We will jump right into the fallback path.
printf ("transaction started: %u\n", status);
_xend ();
}
else
{
printf ("fallback path: %u\n", status);
// xtest should tell us no transaction is currently active.
printf ("xtest: %u\n", _xtest ());
}
printf ("transaction done: %u\n", status);
// Aborting a non-existing transaction is just a NOP.
_xabort (1);
// Still no transaction active.
printf ("xtest: %u\n", _xtest ());
return 0;
}
$ gcc -g -Wall -mrtm -o rtm-test rtm-test.c
$ valgrind ./rtm-test
==14425== Command: ./rtm-test
==14425==
fallback path: 8
xtest: 0
transaction done: 8
vex amd64->IR: unhandled instruction bytes: 0xC6 0xF8 0x1 0xF 0x1 0xD6 0xF 0x95
vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0
vex amd64->IR: VEX=0 VEX.L=0 VEX.nVVVV=0x0 ESC=NONE
vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0
==14425== valgrind: Unrecognised instruction at address 0x4005ae.
==14425== at 0x4005AE: main (rtm-test.c:28)
That is the xabort.
Expected output:
==14468== Memcheck, a memory error detector
==14468== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==14468== Using Valgrind-3.9.0.SVN and LibVEX; rerun with -h for copyright info
==14468== Command: ./rtm-test
==14468==
fallback path: 8
xtest: 0
transaction done: 8
xtest: 0
==14468==
==14468== HEAP SUMMARY:
==14468== in use at exit: 0 bytes in 0 blocks
==14468== total heap usage: 0 allocs, 0 frees, 0 bytes allocated
==14468==
==14468== All heap blocks were freed -- no leaks are possible
==14468==
==14468== For counts of detected and suppressed errors, rerun with: -v
==14468== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 2 from 2)
There is a proposed upstream patch in the upstream bug tracker:
https://bugs.kde.org/show_bug.cgi?id=328100
This request was resolved in Red Hat Enterprise Linux 7.0.
Contact your manager or support representative in case you have further questions about the request.
Take the following program: // gcc -g -Wall -mrtm -o rtm-test rtm-test.c #include <immintrin.h> #include <stdio.h> int main (int argc, char **argv) { unsigned status; if ((status = _xbegin ()) == _XBEGIN_STARTED) { // Note that under valgrind the transaction will never start. // We will jump right into the fallback path. printf ("transaction started: %u\n", status); _xend (); } else { printf ("fallback path: %u\n", status); // xtest should tell us no transaction is currently active. printf ("xtest: %u\n", _xtest ()); } printf ("transaction done: %u\n", status); // Aborting a non-existing transaction is just a NOP. _xabort (1); // Still no transaction active. printf ("xtest: %u\n", _xtest ()); return 0; } $ gcc -g -Wall -mrtm -o rtm-test rtm-test.c $ valgrind ./rtm-test ==14425== Command: ./rtm-test ==14425== fallback path: 8 xtest: 0 transaction done: 8 vex amd64->IR: unhandled instruction bytes: 0xC6 0xF8 0x1 0xF 0x1 0xD6 0xF 0x95 vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0 vex amd64->IR: VEX=0 VEX.L=0 VEX.nVVVV=0x0 ESC=NONE vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0 ==14425== valgrind: Unrecognised instruction at address 0x4005ae. ==14425== at 0x4005AE: main (rtm-test.c:28) That is the xabort. Expected output: ==14468== Memcheck, a memory error detector ==14468== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al. ==14468== Using Valgrind-3.9.0.SVN and LibVEX; rerun with -h for copyright info ==14468== Command: ./rtm-test ==14468== fallback path: 8 xtest: 0 transaction done: 8 xtest: 0 ==14468== ==14468== HEAP SUMMARY: ==14468== in use at exit: 0 bytes in 0 blocks ==14468== total heap usage: 0 allocs, 0 frees, 0 bytes allocated ==14468== ==14468== All heap blocks were freed -- no leaks are possible ==14468== ==14468== For counts of detected and suppressed errors, rerun with: -v ==14468== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 2 from 2) There is a proposed upstream patch in the upstream bug tracker: https://bugs.kde.org/show_bug.cgi?id=328100