[patch] Backport fixes for PR54146 to GCC 4.7

[Steven Bosscher]

Hello,

This patch back-ports most of the changes made to resolve the worst of
PR54146 on trunk to GCC 4.7. This PR is basically an accumulation of
various compiler speed and memory usage regressions, and all fixes are
almost trivial, so I think it's fair and safe to back-port these
changes.

Bootstrapped&tested (gcc-4_7-branch, of course) on
x86_64-unknown-linux-gnu, and on powerpc64-unknown-linux-gnu. OK?

Ciao!
Steven
-------------- next part --------------
A non-text attachment was scrubbed...
Name: PR54146_gcc47.diff
Type: application/octet-stream
Size: 68398 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20120821/4adb5c7d/attachment.obj>