Automatically Tuned Linear Algebra Soft. / Patches / #40 Fix possible crash when tuning prefetch distance

#40 Fix possible crash when tuning prefetch distance

Milestone: developer

Status: closed-accepted

Owner: R. Clint Whaley

Labels: proposed bug fix (23)

Priority: 5

Updated: 2011-01-13

Created: 2010-12-22

Creator: Michael Kistler

Private: No

This patch fixes a crash (segfault) that can occur in tuning prefetch distance for gemv/ger kernels when no kernel was found to have MFLOPS > 0. This can occur when nreps is too small for the platform. The crash occurs because TuneBestPF finds no "best kernel", so it never sets kpB, but then tries to return CloneMVNode(kpB) without first checking to make sure it is non-null. This patch adds the necessary checks for kpB == null, but also adds an additional level of looping the timing functions to increase nreps and re-time whenever the observed time for the kernel is 0.

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Michael Kistler - 2010-12-22

Fix for possible crash when tuning prefetch distance

fix_tune_pfdist_crash.diff

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Michael Kistler - 2010-12-22

assigned_to: nobody --> rwhaley
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R. Clint Whaley - 2011-01-13

Made similar changes to basefiles.

Thanks!
Clint

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R. Clint Whaley - 2011-01-13

milestone: --> developer

labels: --> proposed bug fix

status: open --> closed-accepted
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Fix possible crash when tuning prefetch distance

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#40 Fix possible crash when tuning prefetch distance

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