GMP 6.0.0a on AMD A8-6600K

[tg at gmplib.org]

Kevin Buckley <kevin.m.buckley at gmail.com> writes:

  > Version?  The command "xl info" should give you that.
  
  4.1
  
This is old, but according to its release notes it should support AVX
(the first release that did, in fact).
  
  => 0x000000000040214f <+79>:    vmovsd 0x9031(%rip),%xmm2        # 0x40b188
  
That's indeed an AVX instruction.

I have lost track on things here, the needed information has been spread
in 10 messages instead of the usual or two one.  I don't have time to
lay the puzzle to see if all pieces exist.

This is, as Niels said, in compiler generated code.  Current GMP (i.e.,
a snapshot) will pass -mno-avx to the compiler if the OS correctly tells
us that AVX is unsupported.

Can you see that it tries that in the configure run output?  Does it
fail?  It the compiler generates AVX instructions but cannot be told to
stop, then this is not in GMP's power to fix.  (We could tell it to
compile for an old CPU, but that would cause poor code to be genareted,
or to avoid trhat, would require us to include a list of bad GCC
releases...)


Torbjörn
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