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[PATCH] i386/x86_64 get_attr_length bugfixes


I've used attached script on -S -dp compiled i386/x86_64 sources to find
various bugs in config/i386/ instruction length computation.
This patch fixes all bugs found in -O2 {-m32,-m64} insn-attrtab.i
compilation and most bugs found in -O3 -fpic {-m32,-m64} tramp3d-v4.ii
compilation.  The script isn't perfect, e.g. it doesn't handle multi-insn
instructions (like return_long_internal, which contain \;, or e.g. set_got
(which is wrong anyway, 11 bytes actual vs. 12 bytes returned by
get_attr_length)), but for finding bugs in length computations is quite useful.
The script is invoked with a list of -S -dp compiled files, like:
./ *.s
asflags=-32 ./ *.s
for -m32 compiled stuff).

I've also run the vanilla and patched gcc on a collection of preprocessed
gcc sources, with -O2 {-m32,-m64} and -O3 -fpic {-m32 -march=core2,-m64},
results of the script attached.  There is still work to do, but the patch
already grew quite a bit, so I'd prefer to do further bugfixes in followup
patches.  From the results* tarball it is clear that the patch does
substantial improvements in the insn length computation, especially for -m64
compiled code.

My primary reason for working on this is to make get_attr_length good enough
to be usable in min_insn_size for non-jump insns other than

Bootstrapped/regtested on x86_64-linux and i686-linux.  Ok for trunk?


Attachment: Y311l
Description: Text document

Description: Bourne shell script

Attachment: results.S.-dp.tar.bz2
Description: BZip2 compressed data

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