http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47943
Summary: PRE fails to move a load before a loop with LTO
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: lto
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: jamb...@gcc.gnu.org
When compiling the provided testcase with LTO, PRE fails to hoist the
load of reg->node from the loop. Though this slows down the testcase
only marginally, it has a substantial performance impact for
462.libquantum from SPEC 2006.
When compiling the test case without LTO, PRE does move the load
before the loop.
Observed at least with trunk revision 170357 (2011-02-21), compiling
at -Ofast with and without -flto.
