[PATCH] [X86] Fix pattern match for 32-to-64-bit zext in the presence of AssertSext

[Michael Kuperstein]

On second thought, I could just get rid of most things after the zext - they were good for the reproducer, but probably not needed for the testcase. 
The or before the first trunc is a must as that's what causes the AssertSext to be valid. 
I'll try to reduce the testcase and upload a new patch.

http://reviews.llvm.org/D6128