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* [Bug target/29100] New: use of fmac causes excess precision problems
@ 2006-09-15 16:04 amylaar at gcc dot gnu dot org
2006-09-15 16:14 ` [Bug target/29100] " amylaar at gcc dot gnu dot org
2006-11-15 17:19 ` amylaar at gcc dot gnu dot org
0 siblings, 2 replies; 3+ messages in thread
From: amylaar at gcc dot gnu dot org @ 2006-09-15 16:04 UTC (permalink / raw)
To: gcc-bugs
The use of fmac (-m2e, -m3e, m4-single-only) causes excess precision
problems, which show up when running paranoia:
-Multiplication appears to round correctly.
+* is neither chopped nor correctly rounded.
-Checking for sticky bit.
-Sticky bit apparently used correctly.
+Sticky bit used incorrectly or not at all.
+FLAW: lack(s) of guard digits or failure(s) to correctly round or chop
+(noted above) count as one flaw in the final tally below.
--
Summary: use of fmac causes excess precision problems
Product: gcc
Version: 4.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: amylaar at gcc dot gnu dot org
GCC target triplet: sh-elf
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29100
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/29100] use of fmac causes excess precision problems
2006-09-15 16:04 [Bug target/29100] New: use of fmac causes excess precision problems amylaar at gcc dot gnu dot org
@ 2006-09-15 16:14 ` amylaar at gcc dot gnu dot org
2006-11-15 17:19 ` amylaar at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: amylaar at gcc dot gnu dot org @ 2006-09-15 16:14 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from amylaar at gcc dot gnu dot org 2006-09-15 16:14 -------
Created an attachment (id=12277)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12277&action=view)
patch to add -mfused-madd option
It is debatable what the right default for this option should be.
When that is decided, a patch for invoke.texi should be added to
document the option.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29100
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/29100] use of fmac causes excess precision problems
2006-09-15 16:04 [Bug target/29100] New: use of fmac causes excess precision problems amylaar at gcc dot gnu dot org
2006-09-15 16:14 ` [Bug target/29100] " amylaar at gcc dot gnu dot org
@ 2006-11-15 17:19 ` amylaar at gcc dot gnu dot org
1 sibling, 0 replies; 3+ messages in thread
From: amylaar at gcc dot gnu dot org @ 2006-11-15 17:19 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from amylaar at gcc dot gnu dot org 2006-11-15 17:18 -------
Fixed with merge from 2006-11-03.
--
amylaar at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29100
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2006-11-15 17:19 UTC | newest]
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2006-09-15 16:04 [Bug target/29100] New: use of fmac causes excess precision problems amylaar at gcc dot gnu dot org
2006-09-15 16:14 ` [Bug target/29100] " amylaar at gcc dot gnu dot org
2006-11-15 17:19 ` amylaar at gcc dot gnu dot org
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