[X86] Pre-commit test case showing bug in combineOr (X86ISelLowering.cpp)

[X86] Pre-commit test case showing bug in combineOr (X86ISelLowering.cpp)

In combineOr (X86ISelLowering.cpp) there is a DAG combine that rewrite
a "(0 - SetCC) | C" pattern into something simpler given that a LEA
can be used. Another requirement is that C has some specific value,
for example 1 or 7. When doing that check it is using a 32-bit
unsigned variable to store the value of C. So for a 64-bit OR this
could miscompile in case any of the 32 most significant bits in C
are set.

This patch adds a test case to show this miscompile bug.

Differential Revision: https://reviews.llvm.org/D134890