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From: Julian S. <js...@ac...> - 2006-04-03 01:17:24
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Last week I had a major go at cleaning up and restructuring the
debug info reader module. It has been a bit of a tangle
for a while. The new structure looks like this (all inside
coregrind/m_debuginfo):
debuginfo.c
readelf.c
readdwarf.c readstabs.c
storage.c
Each .c can only call those below it on the page.
storage.c contains the SegInfo structure and stuff for
maintaining/searching arrays of symbols, line-numbers, and Dwarf CF
info records.
readdwarf.c and readstabs.c parse the relevant kind of info and
call storage.c to store the results.
readelf.c reads ELF format, hands syms directly to storage.c,
then delegates to readdwarf.c/readstabs.c for debug info. All
straightforward.
debuginfo.c is the top-level file, and is quite small.
There are 3 goals to this:
(1) Generally tidy up something which needs tidying up
(2) Introduce more modularity, so as to make it easier to add
readers for other formats, if needed
(3) Simplify the stabs reader.
Rationale for (1) and (2) are obvious.
Re (3), the stabs reader has for a good year contained a sophisticated
and impressive parser for stabs strings, with the aim of recording in
detail the types of variables (I think) (Jeremy's work). Unfortunately
that has caused various segfaults reading stabs info in the past few months
(#77869, #117936, #119914, #120345 and another to do with deeply nested
template types).
The worst thing is that it is the stabs type reader that is crashing,
not the stabs line-number reader, but the type info is only used by
Helgrind, which is looking pretty dead at the moment. I propose to lift
out the type-reader code and put it in a separate text file for safe storage,
just leaving the line-number reader in place.
If Helgrind ever does come back to life we will need to reinstate the type
storage/reader stuff but with DWARF as its primary target. Placing the
existing stabs type-reader in hibernation improves stability whilst
retaining the development effort/expertise that went into it for possible
future reinstatement.
Comments?
J
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From: Nicholas N. <nj...@cs...> - 2006-04-03 02:29:52
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On Mon, 3 Apr 2006, Julian Seward wrote: > Last week I had a major go at cleaning up and restructuring the > debug info reader module. > [...] > If Helgrind ever does come back to life we will need to reinstate the type > storage/reader stuff but with DWARF as its primary target. Placing the > existing stabs type-reader in hibernation improves stability whilst > retaining the development effort/expertise that went into it for possible > future reinstatement. And maximizing shareholder value. > Comments? Sounds ok to me. Nick |
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From: Robert W. <rj...@du...> - 2006-04-03 03:06:55
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> And maximizing shareholder value. :-) > > Comments? >=20 > Sounds ok to me. Looks good to me, too. --=20 Robert Walsh Amalgamated Durables, Inc. - "We don't make the things you buy." Email: rj...@du... |