| ; Test that GCSE uses basicaa to do alias analysis, which is capable of |
| ; disambiguating some obvious cases. All loads should be removable in |
| ; this testcase. |
| |
| ; RUN: llvm-as < %s | opt -basicaa -load-vn -gcse -instcombine -dce | llvm-dis | not grep load |
| |
| %A = global int 7 |
| %B = global int 8 |
| implementation |
| |
| int %test() { |
| %A1 = load int* %A |
| |
| store int 123, int* %B ; Store cannot alias %A |
| |
| %A2 = load int* %A |
| %X = sub int %A1, %A2 |
| ret int %X |
| } |
| |
| int %test2() { |
| %A1 = load int* %A |
| br label %Loop |
| Loop: |
| %AP = phi int [0, %0], [%X, %Loop] |
| store int %AP, int* %B ; Store cannot alias %A |
| |
| %A2 = load int* %A |
| %X = sub int %A1, %A2 |
| %c = seteq int %X, 0 |
| br bool %c, label %out, label %Loop |
| |
| out: |
| ret int %X |
| } |
| |