forked from OSchip/llvm-project
47 lines
935 B
LLVM
47 lines
935 B
LLVM
; Test that GCSE uses basicaa to do alias analysis, which is capable of
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; disambiguating some obvious cases. All loads should be removable in
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; this testcase.
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; RUN: llvm-upgrade < %s | llvm-as | opt -basicaa -load-vn -gcse -instcombine -dce | llvm-dis | not grep load
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%A = global int 7
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%B = global int 8
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implementation
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int %test() {
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%A1 = load int* %A
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store int 123, int* %B ; Store cannot alias %A
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%A2 = load int* %A
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%X = sub int %A1, %A2
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ret int %X
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}
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int %test2() {
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%A1 = load int* %A
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br label %Loop
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Loop:
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%AP = phi int [0, %0], [%X, %Loop]
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store int %AP, int* %B ; Store cannot alias %A
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%A2 = load int* %A
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%X = sub int %A1, %A2
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%c = seteq int %X, 0
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br bool %c, label %out, label %Loop
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out:
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ret int %X
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}
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declare void %external()
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int %test3() {
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%X = alloca int
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store int 7, int* %X
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call void %external()
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%V = load int* %X
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ret int %V
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}
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