| ; This testcase tests for various features the basicaa test should be able to |
| ; determine, as noted in the comments. |
| |
| ; RUN: llvm-as < %s | opt -basicaa -gvn -instcombine -dce | llvm-dis | not grep REMOVE |
| |
| @Global = external global { i32 } |
| |
| ; Array test: Test that operations on one local array do not invalidate |
| ; operations on another array. Important for scientific codes. |
| ; |
| define i32 @different_array_test(i64 %A, i64 %B) { |
| %Array1 = alloca i32, i32 100 |
| %Array2 = alloca i32, i32 200 |
| |
| %pointer = getelementptr i32* %Array1, i64 %A |
| %val = load i32* %pointer |
| |
| %pointer2 = getelementptr i32* %Array2, i64 %B |
| store i32 7, i32* %pointer2 |
| |
| %REMOVE = load i32* %pointer ; redundant with above load |
| %retval = sub i32 %REMOVE, %val |
| ret i32 %retval |
| } |
| |
| ; Constant index test: Constant indexes into the same array should not |
| ; interfere with each other. Again, important for scientific codes. |
| ; |
| define i32 @constant_array_index_test() { |
| %Array = alloca i32, i32 100 |
| %P1 = getelementptr i32* %Array, i64 7 |
| %P2 = getelementptr i32* %Array, i64 6 |
| |
| %A = load i32* %P1 |
| store i32 1, i32* %P2 ; Should not invalidate load |
| %BREMOVE = load i32* %P1 |
| %Val = sub i32 %A, %BREMOVE |
| ret i32 %Val |
| } |
| |
| ; Test that if two pointers are spaced out by a constant getelementptr, that |
| ; they cannot alias. |
| define i32 @gep_distance_test(i32* %A) { |
| %REMOVEu = load i32* %A |
| %B = getelementptr i32* %A, i64 2 ; Cannot alias A |
| store i32 7, i32* %B |
| %REMOVEv = load i32* %A |
| %r = sub i32 %REMOVEu, %REMOVEv |
| ret i32 %r |
| } |
| |
| ; Test that if two pointers are spaced out by a constant offset, that they |
| ; cannot alias, even if there is a variable offset between them... |
| define i32 @gep_distance_test2({i32,i32}* %A, i64 %distance) { |
| %A1 = getelementptr {i32,i32}* %A, i64 0, i32 0 |
| %REMOVEu = load i32* %A1 |
| %B = getelementptr {i32,i32}* %A, i64 %distance, i32 1 |
| store i32 7, i32* %B ; B cannot alias A, it's at least 4 bytes away |
| %REMOVEv = load i32* %A1 |
| %r = sub i32 %REMOVEu, %REMOVEv |
| ret i32 %r |
| } |
| |
| ; Test that we can do funny pointer things and that distance calc will still |
| ; work. |
| define i32 @gep_distance_test3(i32 * %A) { |
| %X = load i32* %A |
| %B = bitcast i32* %A to i8* |
| %C = getelementptr i8* %B, i64 4 |
| %Y = load i8* %C |
| ret i32 8 |
| } |
| |
| ; Test that we can disambiguate globals reached through constantexpr geps |
| define i32 @constexpr_test() { |
| %X = alloca i32 |
| %Y = load i32* %X |
| store i32 5, i32* getelementptr ({ i32 }* @Global, i64 0, i32 0) |
| %REMOVE = load i32* %X |
| %retval = sub i32 %Y, %REMOVE |
| ret i32 %retval |
| } |