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Subject: Re: What is the portable 128-bit floating point type?
To: Konstantin Belousov <kostikbel@gmail.com>
Cc: Freebsd hackers list <freebsd-hackers@freebsd.org>
References: <eb15d9e4-c1d4-3886-a3b7-1264c12396cd@rawbw.com>
 <20190525200437.GV2748@kib.kiev.ua>
From: Yuri <yuri@rawbw.com>
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Date: Sat, 25 May 2019 13:50:24 -0700
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On 2019-05-25 13:04, Konstantin Belousov wrote:
> Neither i386 nor amd64 have hardware-supported 128 bit floating point
> type. long double is defined by both i386 and amd64 Unix ABI as 80 bits
> (10 bytes) representation as defined by IEEEE FP standard and supported
> by x87 FPU (not-SSE). The difference in size is due to the different
> natural alignment between 32 and 64 bit ISA.


So it looks like there is no true quad-precision float available.


Based on this conversation https://github.com/bluescarni/mppp/issues/186 
FreeBSD used to support __float128. Why was it removed?


Yuri