Do not try to optimize PHI nodes with incredibly high degree.  This reduces SCCP
time from 615s to 1.49s on a large testcase that has a gigantic switch statement
that all of the blocks in the function go to (an intepreter).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12442 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed