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Re: Recent new atf test failures

On Wed, 26 Mar 2014, David Laight wrote:

On Wed, Mar 26, 2014 at 12:25:53PM -0700, Paul Goyette wrote:
Some time in the last two weeks, we've had a few new test cases failing
in my amd64 test-bed.

Tests that used to pass, but currently failing


Tests that currently fail, but don't seem to exist in older builds


Those are some more extensive tests for exp2().

The exp2_powers tests are failing to generate an 'overflow' result.
They work for me on a real system - so it might be a qemu issue?

Maybe qemu is using the x87 fpu (with 80 bit precision) to emulate
the 64bit (and 32bit) SSE2 double (and float) maths - so the large
mutiplies used to generate overflow fail.

Ah, OK.

Actually, I wonder, have you rebuilt qemu since jeorg changed the
default x87 precision to 80bits?
That might be the difference between your tests and gson's tests
(which only show some minor errors for exp2f(7.7) and exp2f(8.8).

No, I have not updated my qemu recently (several months).

The exp2_values tests is showing up something odd in FP maths.
I've not changes the exp2f() code, but I'm seeing different
errors in my own testing (native on amd64) from earlier tests.
However it might just be that the allowed error is too small.

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