[InstSimplify] Fix missed optimization in simplifyUnsignedRangeCheck()
For both operands are unsigned, the following optimizations are valid, and missing:
1. X > Y && X != 0 --> X > Y
2. X > Y || X != 0 --> X != 0
3. X <= Y || X != 0 --> true
4. X <= Y || X == 0 --> X <= Y
5. X > Y && X == 0 --> false
unsigned foo(unsigned x, unsigned y) { return x > y && x != 0; }
should fold to x > y, but I found we haven't done it right now.
besides, unsigned foo(unsigned x, unsigned y) { return x < y && y != 0; }
Has been folded to x < y, so there may be a bug.
Patch by: Li Jia He!
Differential Revision: https://reviews.llvm.org/D47922
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335129
91177308-0d34-0410-b5e6-
96231b3b80d8