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Cc: kostikbel@gmail.com, freebsd-hackers@freebsd.org, dchagin@freebsd.org
Subject: Re: GSoC'11: DWARF2 call frame information
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Xingxing Pan <mprc.pku.edu.cn> wrote:

> Dose full register tracking means to emit DWARF for all the
> registers's saving and restoring in the life time of the function?

Most assembly functions are leaves, so saving/restoring around
calls to lower-level functions will be infrequent.  I suspect
it would be more useful to emit debug records that show how the
registers are being used, so that gdb can display meaningful
names along with their values.  And yes, this requires reading
and understanding the comments if the code is well commented,
or analyzing the code if it is not well commented.  It can't be
automated.