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From: "joseph at codesourcery dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/60181] constant folding of complex number incorrect Date: Thu, 13 Feb 2014 18:09:00 -0000 [thread overview] Message-ID: <bug-60181-4-wuGTJE9LMk@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-60181-4@http.gcc.gnu.org/bugzilla/> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- There are no specified accuracy requirements for complex multiplication / division, even under Annex G (parts of which - imaginary types in particular - are not implemented in GCC at present), beyond certain requirements for special cases and avoiding certain cases of overflow from the simplest formulas. Constant folding is correctly rounding, runtime complex multiplication / division isn't (and given complaints about slowness at present, I don't think users would want it to be even slower, though there may well be a case for defining a standard library interface for correctly rounding complex multiplication / division). x86 probably benefits from excess precision being used implicitly by GCC when compiling the implementations of complex multiplication and division.
next prev parent reply other threads:[~2014-02-13 18:09 UTC|newest] Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top 2014-02-13 16:19 [Bug target/60181] New: " krebbel at gcc dot gnu.org 2014-02-13 18:09 ` joseph at codesourcery dot com [this message] 2014-02-14 9:37 ` [Bug target/60181] " rguenth at gcc dot gnu.org 2014-02-14 11:59 ` krebbel at gcc dot gnu.org 2014-02-14 15:34 ` pinskia at gcc dot gnu.org 2014-10-02 14:52 ` boger at us dot ibm.com 2014-10-02 15:38 ` boger at us dot ibm.com 2014-10-02 15:47 ` dje at gcc dot gnu.org 2014-10-02 16:10 ` pinskia at gcc dot gnu.org
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