forked from OSchip/llvm-project
24 lines
703 B
LLVM
24 lines
703 B
LLVM
; This testcase tests for a problem where LICM hoists loads out of a loop
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; despite the fact that calls to unknown functions may modify what is being
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; loaded from. Basically if the load gets hoisted, the subtract gets turned
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; into a constant zero.
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;
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; RUN: llvm-as < %s | opt -licm -gvn -instcombine | llvm-dis | grep load
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@X = global i32 7 ; <i32*> [#uses=2]
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declare void @foo()
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define i32 @test(i1 %c) {
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%A = load i32* @X ; <i32> [#uses=1]
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br label %Loop
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Loop: ; preds = %Loop, %0
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call void @foo( )
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;; Should not hoist this load!
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%B = load i32* @X ; <i32> [#uses=1]
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br i1 %c, label %Loop, label %Out
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Out: ; preds = %Loop
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%C = sub i32 %A, %B ; <i32> [#uses=1]
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ret i32 %C
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}
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