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| author | Joseph Myers <joseph@codesourcery.com> | 2015-11-11 00:06:09 +0000 |
|---|---|---|
| committer | Joseph Myers <joseph@codesourcery.com> | 2015-11-11 00:06:09 +0000 |
| commit | 71d1b0166b4ace0d804af2993b3815758b852efc (patch) | |
| tree | 1cfe69ef93cf1fa482ecbd57dc324cd2494895a1 /ChangeLog | |
| parent | fe534fe8980fa214c410e3661a4216e781073353 (diff) | |
| download | glibc-71d1b0166b4ace0d804af2993b3815758b852efc.tar.gz glibc-71d1b0166b4ace0d804af2993b3815758b852efc.tar.xz glibc-71d1b0166b4ace0d804af2993b3815758b852efc.zip | |
Fix powerpc nearbyint wrongly clearing "inexact" and leaving traps disabled (bug 19228).
Similar to bug 15491 recently fixed for x86_64 / x86, the powerpc (both powerpc32 and powerpc64) hard-float implementations of nearbyintf and nearbyint wrongly clear an "inexact" exception that was raised before the function was called; this shows up as failure of the test math/test-nearbyint-except added when that bug was fixed. They also wrongly leave traps on "inexact" disabled if they were enabled before the function was called. This patch fixes the bugs similar to how the x86 bug was fixed: saving and restoring the whole floating-point state, both to restore the original "inexact" flag state and to restore the original state of whether traps on "inexact" were enabled. Because there's a convenient point in the powerpc implementations to save state after any sNaN arguments will have raised "invalid" but before "inexact" traps need to be disabled, no special handling for "invalid" is needed as in the x86 version. Tested for powerpc64 and powerpc32, where it fixes the math/test-nearbyint-except failure as well as fixing the new test math/test-nearbyint-except-2 added by this patch. Also tested for x86_64 and x86 that the new test passes. If powerpc experts see a more efficient way of doing this (e.g. instruction positioning that's better for pipelines on typical processors) then of course followups optimizing the fix are welcome. [BZ #19228] * sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S (__nearbyint): Save and restore full floating-point state. * sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S (__nearbyintf): Likewise. * sysdeps/powerpc/powerpc64/fpu/s_nearbyint.S (__nearbyint): Likewise. * sysdeps/powerpc/powerpc64/fpu/s_nearbyintf.S (__nearbyintf): Likewise. * math/test-nearbyint-except-2.c: New file. * math/Makefile (tests): Add test-nearbyint-except-2.
Diffstat (limited to 'ChangeLog')
| -rw-r--r-- | ChangeLog | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 51faaed4c2..b23297b29b 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,17 @@ +2015-11-10 Joseph Myers <joseph@codesourcery.com> + + [BZ #19228] + * sysdeps/powerpc/powerpc32/fpu/s_nearbyint.S (__nearbyint): Save + and restore full floating-point state. + * sysdeps/powerpc/powerpc32/fpu/s_nearbyintf.S (__nearbyintf): + Likewise. + * sysdeps/powerpc/powerpc64/fpu/s_nearbyint.S (__nearbyint): + Likewise. + * sysdeps/powerpc/powerpc64/fpu/s_nearbyintf.S (__nearbyintf): + Likewise. + * math/test-nearbyint-except-2.c: New file. + * math/Makefile (tests): Add test-nearbyint-except-2. + 2015-11-10 H.J. Lu <hongjiu.lu@intel.com> [BZ #19178] |