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prologue detection
- From: "Frank Ch. Eigler" <fche at elastic dot org>
- To: systemtap at sources dot redhat dot com
- Date: Fri, 7 Apr 2006 10:21:33 -0400
- Subject: prologue detection
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Hi -
While trying to run some measurements on the static instrumentation
code, I came across an amusing and troubling bug in the translator's
prologue-detection heuristic. For some classes of functions (in this
case, prologue-less ones), it would get it totally wrong, and
designate an instruction within a subsequent block. I've seen one
case where the probe was placed *beyond* the requested function.
I'm taking a little detour to try to simplify & fix this part up. In
the mean time, you may want to double-check the placement of probes in
your scripts, especially when on short funtions. Please send me
anything suspicious that you may have recently seen.
- FChE