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; 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 -load-vn -gcse -instcombine -dce | llvm-dis | not grep REMOVE
%Global = external global { int }
implementation
; Array test: Test that operations on one local array do not invalidate
; operations on another array. Important for scientific codes.
;
int %different_array_test(long %A, long %B) {
%Array1 = alloca int, uint 100
%Array2 = alloca int, uint 200
%pointer = getelementptr int* %Array1, long %A
%val = load int* %pointer
%pointer2 = getelementptr int* %Array2, long %B
store int 7, int* %pointer2
%REMOVE = load int* %pointer ; redundant with above load
%retval = sub int %REMOVE, %val
ret int %retval
}
; Constant index test: Constant indexes into the same array should not
; interfere with each other. Again, important for scientific codes.
;
int %constant_array_index_test() {
%Array = alloca int, uint 100
%P1 = getelementptr int* %Array, long 7
%P2 = getelementptr int* %Array, long 6
%A = load int* %P1
store int 1, int* %P2 ; Should not invalidate load
%BREMOVE = load int* %P1
%Val = sub int %A, %BREMOVE
ret int %Val
}
; Test that if two pointers are spaced out by a constant getelementptr, that
; they cannot alias.
int %gep_distance_test(int* %A) {
%REMOVEu = load int* %A
%B = getelementptr int* %A, long 2 ; Cannot alias A
store int 7, int* %B
%REMOVEv = load int* %A
%r = sub int %REMOVEu, %REMOVEv
ret int %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...
int %gep_distance_test2({int,int}* %A, long %distance) {
%A = getelementptr {int,int}* %A, long 0, uint 0
%REMOVEu = load int* %A
%B = getelementptr {int,int}* %A, long %distance, uint 1
store int 7, int* %B ; B cannot alias A, it's at least 4 bytes away
%REMOVEv = load int* %A
%r = sub int %REMOVEu, %REMOVEv
ret int %r
}
; Test that we can do funny pointer things and that distance calc will still
; work.
int %gep_distance_test3(int * %A) {
%X = load int* %A
%B = cast int* %A to sbyte*
%C = getelementptr sbyte* %B, long 4
%Y = load sbyte* %C
ret int 8
}
; Test that we can disambiguate globals reached through constantexpr geps
int %constexpr_test() {
%X = alloca int
%Y = load int* %X
store int 5, int* getelementptr ({ int }* %Global, long 0, uint 0)
%REMOVE = load int* %X
%retval = sub int %Y, %REMOVE
ret int %retval
}
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