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* [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results
@ 2014-01-08 12:01 azanella at linux dot vnet.ibm.com
2014-01-08 12:04 ` [Bug math/16414] " azanella at linux dot vnet.ibm.com
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: azanella at linux dot vnet.ibm.com @ 2014-01-08 12:01 UTC (permalink / raw)
To: glibc-bugs
https://sourceware.org/bugzilla/show_bug.cgi?id=16414
Bug ID: 16414
Summary: IBM long double truncl assembly implementation showing
wrong results
Product: glibc
Version: 2.19
Status: NEW
Severity: normal
Priority: P2
Component: math
Assignee: unassigned at sourceware dot org
Reporter: azanella at linux dot vnet.ibm.com
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^ permalink raw reply [flat|nested] 5+ messages in thread* [Bug math/16414] IBM long double truncl assembly implementation showing wrong results 2014-01-08 12:01 [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results azanella at linux dot vnet.ibm.com @ 2014-01-08 12:04 ` azanella at linux dot vnet.ibm.com 2014-01-08 12:05 ` azanella at linux dot vnet.ibm.com ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: azanella at linux dot vnet.ibm.com @ 2014-01-08 12:04 UTC (permalink / raw) To: glibc-bugs https://sourceware.org/bugzilla/show_bug.cgi?id=16414 Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |ASSIGNED --- Comment #1 from Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> --- While seeking why some tgammal results shows wrong signal on PPC64, I found out that the assembly implementation truncl (sysdeps/powerpc/powerpc64/fpu/s_truncl.S) for is in fact returning wrong results for some inputs. More specifically, for number where the first double is a exact integer and the precision is determined by second long double. Checking on implementation comments and history, I am very confident the assembly implementation was based on a version before commit 5c68d401698a58cf7da150d9cce769fa6679ba5f that fixes BZ#2423 (Errors in long double (ldbl-128ibm) rounding functions in glibc-2.4), since the implementation indeed does not handle some inputs correctly. A possible solutions is just remove the implementation and make the build select sysdeps/ieee754/ldbl-128ibm/s_truncl.c instead (which contains all the appropriated fixes). (Hit enter button before finishing editing, this comments is the bug description). -- You are receiving this mail because: You are on the CC list for the bug. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug math/16414] IBM long double truncl assembly implementation showing wrong results 2014-01-08 12:01 [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results azanella at linux dot vnet.ibm.com 2014-01-08 12:04 ` [Bug math/16414] " azanella at linux dot vnet.ibm.com @ 2014-01-08 12:05 ` azanella at linux dot vnet.ibm.com 2014-01-08 14:18 ` azanella at linux dot vnet.ibm.com 2014-06-13 9:10 ` fweimer at redhat dot com 3 siblings, 0 replies; 5+ messages in thread From: azanella at linux dot vnet.ibm.com @ 2014-01-08 12:05 UTC (permalink / raw) To: glibc-bugs https://sourceware.org/bugzilla/show_bug.cgi?id=16414 Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |azanella at linux dot vnet.ibm.com Assignee|unassigned at sourceware dot org |azanella at linux dot vnet.ibm.com --- Comment #2 from Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> --- The patch https://sourceware.org/ml/libc-alpha/2014-01/msg00136.html fixes this issue. -- You are receiving this mail because: You are on the CC list for the bug. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug math/16414] IBM long double truncl assembly implementation showing wrong results 2014-01-08 12:01 [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results azanella at linux dot vnet.ibm.com 2014-01-08 12:04 ` [Bug math/16414] " azanella at linux dot vnet.ibm.com 2014-01-08 12:05 ` azanella at linux dot vnet.ibm.com @ 2014-01-08 14:18 ` azanella at linux dot vnet.ibm.com 2014-06-13 9:10 ` fweimer at redhat dot com 3 siblings, 0 replies; 5+ messages in thread From: azanella at linux dot vnet.ibm.com @ 2014-01-08 14:18 UTC (permalink / raw) To: glibc-bugs https://sourceware.org/bugzilla/show_bug.cgi?id=16414 Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED --- Comment #3 from Adhemerval Zanella Netto <azanella at linux dot vnet.ibm.com> --- Fixed by commit 38f3458175ecf7c3588bd5b6e465f4d9205fbe1c. -- You are receiving this mail because: You are on the CC list for the bug. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug math/16414] IBM long double truncl assembly implementation showing wrong results 2014-01-08 12:01 [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results azanella at linux dot vnet.ibm.com ` (2 preceding siblings ...) 2014-01-08 14:18 ` azanella at linux dot vnet.ibm.com @ 2014-06-13 9:10 ` fweimer at redhat dot com 3 siblings, 0 replies; 5+ messages in thread From: fweimer at redhat dot com @ 2014-06-13 9:10 UTC (permalink / raw) To: glibc-bugs https://sourceware.org/bugzilla/show_bug.cgi?id=16414 Florian Weimer <fweimer at redhat dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Flags| |security- -- You are receiving this mail because: You are on the CC list for the bug. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2014-06-13 9:10 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-01-08 12:01 [Bug math/16414] New: IBM long double truncl assembly implementation showing wrong results azanella at linux dot vnet.ibm.com 2014-01-08 12:04 ` [Bug math/16414] " azanella at linux dot vnet.ibm.com 2014-01-08 12:05 ` azanella at linux dot vnet.ibm.com 2014-01-08 14:18 ` azanella at linux dot vnet.ibm.com 2014-06-13 9:10 ` fweimer at redhat dot com
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