[aarch64-port-dev ] 8210461: AArch64: Math.cos intrinsic gives incorrect results

[Andrew Haley]

Please confirm this bug:

Range reduction for trig functions on AArch64 is broken. The smallest
broken case is

Math.cos(1647100)

which should return 0.7833030468809974 but returns
-0.2745634094819721.

The problem is that __kernel_rem_pio2 is supposed to reduce its
argument to the range [-pi/4, pi/4], pi/4 ~ 0.785398164 but it does
not: it returns 1.8489319595787654, which is outside the range of the
polynomial cosine approximation.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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