math: new 'huge' trig tests failing on s390x

[mundaym]

Presumably the s390x assembly implementations, like the old Go implementations, weren't designed to produce the correct result for 'huge' input values.

--- FAIL: TestHugeCos (0.00s)
    all_test.go:3114: Cos(1.329227995784916e+36) = NaN, want -0.9258790228548379
    all_test.go:3114: Cos(1.7668470647783843e+72) = NaN, want 0.9360104259335379
    all_test.go:3114: Cos(3.1217485503159922e+144) = NaN, want -0.2828277764019379
    all_test.go:3114: Cos(1.8919697882131776e+69) = NaN, want -0.14616431394103618
    all_test.go:3114: Cos(2.514859209672214e+105) = NaN, want -0.7945605821067141
    all_test.go:3114: Cos(1.7976931348623157e+308) = NaN, want -0.9999876894265599
--- FAIL: TestHugeSin (0.00s)
    all_test.go:3124: Sin(1.329227995784916e+36) = NaN, want 0.377820109360752
    all_test.go:3124: Sin(1.7668470647783843e+72) = NaN, want -0.35197227524865776
    all_test.go:3124: Sin(3.1217485503159922e+144) = NaN, want 0.9591707089436872
    all_test.go:3124: Sin(1.8919697882131776e+69) = NaN, want 0.9892603263702362
    all_test.go:3124: Sin(2.514859209672214e+105) = NaN, want -0.6071848823564695
    all_test.go:3124: Sin(1.7976931348623157e+308) = NaN, want 0.00496195478918406
--- FAIL: TestHugeTan (0.00s)
    all_test.go:3144: Tan(1.329227995784916e+36) = NaN, want -0.40806638884180424
    all_test.go:3144: Tan(1.7668470647783843e+72) = NaN, want -0.37603456702698074
    all_test.go:3144: Tan(3.1217485503159922e+144) = NaN, want -3.391359650547799
    all_test.go:3144: Tan(1.8919697882131776e+69) = NaN, want -6.76813854009065
    all_test.go:3144: Tan(2.514859209672214e+105) = NaN, want 0.7641769501660493
    all_test.go:3144: Tan(1.7976931348623157e+308) = NaN, want -0.00496201587444489
FAIL
FAIL	math	0.014s

[bcmills]

CC @griesemer @bmkessler for https://golang.org/cl/153059.

[griesemer]

The s390x implementations are inaccurate. We either disable the tests for s390x or we switch to the non-assembly implementation.

[griesemer]

I'm on this.

[gopherbot]

Change https://golang.org/cl/154119 mentions this issue: math: don't run huge argument tests on s390x