[Valgrind-users] Bug in Valgrind 3.7.0

[JVZ <je...@fo...>]

Running a piece of code which called powl() from the math function,
valgrind exits with message like the following:

vex and64->IR: unhandled instruction bytes: 0xDA 0xE9 0xDF 0xE0
valgrind: Unrecognized instruction at address: 0x3411235BF4.
<blabla>

Illegal opcode at address 0x3411235BF4:
  at 0x3411235BF4:  __ieee754_powl (in /lib64/libm-2.5.so)
  ........


I checked and this turns out to be a fragment in the __ieee754_powl() routine
executing these two instructions:

	fucompp	
	fnstsw

This fragment appears also unchanged in later versions of the glibc math library,
for x86-64 architecture.


I checked Bugzilla, it doesn't seem listed in the bugs database already.


Hopefully, this is something that can be fixed in next version of valgrind...


	
				-- JVZ