remove use of INLINE_YL2X from std.math

[thewilsonator]

rebases #3310

[thewilsonator]

std/internal/math/gammafunction.d(569): [unittest] unittest failure
assert(logGamma(-50.2L) == log(fabs(gamma(-50.2L))));
e: relaxed to
assert(feqrel(logGamma(-50.2L),log(fabs(gamma(-50.2L)))) > real.mant_dig-2);

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[thewilsonator]

std\internal\math\gammafunction.d(1045): [unittest] unittest failure
assert(feqrel(betaIncompleteInv(5, 10, 0.2000002972865658842L), 0.229121208190918L) >= real.mant_dig - 3);

[ibuclaw]

std/internal/math/gammafunction.d(569): [unittest] unittest failure
assert(logGamma(-50.2L) == log(fabs(gamma(-50.2L))));
e: relaxed to
assert(feqrel(logGamma(-50.2L),log(fabs(gamma(-50.2L)))) > real.mant_dig-2);

I'll have to check, but I think that similar relaxations also exist in gdc's fork as well.

[thewilsonator]

actually could you do me a favour and upstream the relaxations

[ibuclaw]

actually could you do me a favour and upstream the relaxations

I'm looking at the first failure in dmd

assert(logGamma(-50.2L) == log(fabs(gamma(-50.2L))));

I don't see any deviation with the unittest in gdc, and yet there is no failure. On inspection, it looks like most if not all of logGamma and gamma is inlined and constfolded at compile-time in gdc. So the call to log() for gdc and dmd are receiving two different numbers (same up until the 17th decimal place). I'll have a try on aarch64, as there's sure to be failures there that don't exist on i386/x86_64.

[ibuclaw]

I'll have a try on aarch64, as there's sure to be failures there that don't exist on i386/x86_64.

gammafunction hasn't been ported to 128-bit, so that's a dead end. :-)

[RazvanN7]

@thewilsonator can you rebase this?

[ibuclaw]

@thewilsonator can you rebase this?

Tests will fail if you remove INLINE_Y2LX, so rebasing would be a futile effort.

#7942 (comment)

[RazvanN7]

@ibuclaw Any pointers on how we can fix this?