Bug 134478

valgrind 3.2.1 report "illegal instruction" for code that has CLI/STI.
e.g. with the following code,
int main()
{
   volatile int x;
   asm volatile ("cli");
   x = 0;
   asm volatile ("sti");
   return 0;
}

Valgrind -v generates the following output:-
--14078-- Command line
--14078--    a.out
--14078-- Startup, with flags:
--14078--    -v
--14078-- Contents of /proc/version:
--14078--   Linux version 2.6.16-18_yoda2smp (orbuild@yoran-bldsvr5) (gcc
version 4.0.2 20051125 (Red Hat 4.0.2-8)) #1 SMP PREEMPT Fri May 26 11:33:53 PDT
2006
--14078-- Arch and hwcaps: AMD64, amd64-sse2
--14078-- Valgrind library directory: /opt/or-develtools/lib/valgrind
--14078-- Reading syms from /home/ymei/a.out (0x400000)
--14078-- Reading syms from
/orenv/develtools-fc4-x86_64-ro/lib/valgrind/amd64-linux/memcheck (0x38000000)
--14078--    object doesn't have a symbol table
--14078--    object doesn't have a dynamic symbol table
--14078-- Reading suppressions file: /opt/or-develtools/lib/valgrind/default.supp
--14078-- Reading syms from
/orenv/develtools-fc4-x86_64-ro/lib/valgrind/amd64-linux/vgpreload_core.so
(0x4802000)
--14078--    object doesn't have a symbol table
--14078-- Reading syms from
/orenv/develtools-fc4-x86_64-ro/lib/valgrind/amd64-linux/vgpreload_memcheck.so
(0x4903000)
--14078--    object doesn't have a symbol table
--14078-- REDIR: 0x3DE4C13F90 (index) redirected to 0x4906720 (index)
--14078-- REDIR: 0x3DE4C14140 (strcmp) redirected to 0x49068B0 (strcmp)
--14078-- REDIR: 0x3DE4C14170 (strlen) redirected to 0x49067C0 (strlen)
--14078-- Reading syms from /usr/lib64/libstdc++.so.6.0.7 (0x3DE7500000)
--14078--    object doesn't have a symbol table
--14078-- Reading syms from /lib64/libm-2.3.5.so (0x3DE5100000)
--14078-- Reading syms from /lib64/libgcc_s-4.0.2-20051126.so.1 (0x3DE6D00000)
--14078--    object doesn't have a symbol table
--14078-- Reading syms from /lib64/libc-2.3.5.so (0x3DE4E00000)
--14078-- REDIR: 0x3DE4E72420 (rindex) redirected to 0x49065D0 (rindex)
vex amd64->IR: unhandled instruction bytes: 0xFA 0xC7 0x45 0xFC
==14078== valgrind: Unrecognised instruction at address 0x40051C.
==14078== Your program just tried to execute an instruction that Valgrind
==14078== did not recognise.  There are two possible reasons for this.
==14078== 1. Your program has a bug and erroneously jumped to a non-code
==14078==    location.  If you are running Memcheck and you just saw a
==14078==    warning about a bad jump, it's probably your program's fault.
==14078== 2. The instruction is legitimate but Valgrind doesn't handle it,
==14078==    i.e. it's Valgrind's fault.  If you think this is the case or
==14078==    you are not sure, please let us know and we'll try to fix it.
==14078== Either way, Valgrind will now raise a SIGILL signal which will
==14078== probably kill your program.
==14078== 
==14078== Process terminating with default action of signal 4 (SIGILL): dumping core
==14078==  Illegal opcode at address 0x40051C
==14078==    at 0x40051C: main (in /home/ymei/a.out)
--14078-- REDIR: 0x3DE4E6ABE0 (free) redirected to 0x490575E (free)
--14078-- REDIR: 0x3DE4E733E0 (memset) redirected to 0x4906B00 (memset)
==14078== 
==14078== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 5 from 2)
--14078-- supp:    1 strlen-not-intercepted-early-enough-HACK-5
--14078-- supp:    4 dl_relocate_object
==14078== malloc/free: in use at exit: 0 bytes in 0 blocks.
==14078== malloc/free: 0 allocs, 0 frees, 0 bytes allocated.
==14078== 
==14078== All heap blocks were freed -- no leaks are possible.
--14078--  memcheck: sanity checks: 2 cheap, 1 expensive
--14078--  memcheck: auxmaps: 113 auxmap entries (7232k, 7M) in use
--14078--  memcheck: auxmaps: 423221 searches, 826356 comparisons
--14078--  memcheck: SMs: n_issued      = 19 (304k, 0M)
--14078--  memcheck: SMs: n_deissued    = 0 (0k, 0M)
--14078--  memcheck: SMs: max_noaccess  = 524287 (8388592k, 8191M)
--14078--  memcheck: SMs: max_undefined = 0 (0k, 0M)
--14078--  memcheck: SMs: max_defined   = 138 (2208k, 2M)
--14078--  memcheck: SMs: max_non_DSM   = 19 (304k, 0M)
--14078--  memcheck: max sec V bit nodes:    0 (0k, 0M)
--14078--  memcheck: set_sec_vbits8 calls: 0 (new: 0, updates: 0)
--14078--  memcheck: max shadow mem size:   4448k, 4M
--14078-- translate:            fast SP updates identified: 904 ( 86.5%)
--14078-- translate:   generic_known SP updates identified: 82 (  7.8%)
--14078-- translate: generic_unknown SP updates identified: 59 (  5.6%)
--14078--     tt/tc: 2,904 tt lookups requiring 2,927 probes
--14078--     tt/tc: 2,904 fast-cache updates, 5 flushes
--14078--  transtab: new        1,353 (32,509 -> 615,415; ratio 189:10) [0 scs]
--14078--  transtab: dumped     0 (0 -> ??)
--14078--  transtab: discarded  15 (315 -> ??)
--14078-- scheduler: 255,681 jumps (bb entries).
--14078-- scheduler: 2/1,810 major/minor sched events.
--14078--    sanity: 3 cheap, 1 expensive checks.
--14078--    exectx: 30,011 lists, 5 contexts (avg 0 per list)
--14078--    exectx: 5 searches, 0 full compares (0 per 1000)
--14078--    exectx: 0 cmp2, 10 cmp4, 0 cmpAll
Illegal instruction