Mercurial > hg > CbC > CbC_llvm
view llvm/test/Transforms/GVN/volatile-nonvolatile.ll @ 236:c4bab56944e8 llvm-original
LLVM 16
author | kono |
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date | Wed, 09 Nov 2022 17:45:10 +0900 |
parents | 1d019706d866 |
children | 1f2b6ac9f198 |
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; RUN: opt -gvn -S < %s | FileCheck %s %struct.t = type { i32* } ; The loaded address and the location of the address itself are not aliased, ; so the second reload is not necessary. Check that it can be eliminated. ; CHECK-LABEL: test1 ; CHECK: load ; CHECK-NOT: load define void @test1(%struct.t* nocapture readonly %p, i32 %v) #0 { entry: %m = getelementptr inbounds %struct.t, %struct.t* %p, i32 0, i32 0 %0 = load i32*, i32** %m, align 4, !tbaa !1 store volatile i32 %v, i32* %0, align 4, !tbaa !6 %1 = load i32*, i32** %m, align 4, !tbaa !1 store volatile i32 %v, i32* %1, align 4, !tbaa !6 ret void } ; The store via the loaded address may overwrite the address itself. ; Make sure that both loads remain. ; CHECK-LABEL: test2 ; CHECK: load ; CHECK: store ; CHECK: load define void @test2(%struct.t* nocapture readonly %p, i32 %v) #0 { entry: %m = getelementptr inbounds %struct.t, %struct.t* %p, i32 0, i32 0 %0 = load i32*, i32** %m, align 4, !tbaa !1 store volatile i32 %v, i32* %0, align 4, !tbaa !1 %1 = load i32*, i32** %m, align 4, !tbaa !1 store volatile i32 %v, i32* %1, align 4, !tbaa !1 ret void } ; The loads are ordered and non-monotonic. Although they are not aliased to ; the stores, make sure both are preserved. ; CHECK-LABEL: test3 ; CHECK: load ; CHECK: store ; CHECK: load define void @test3(%struct.t* nocapture readonly %p, i32 %v) #0 { entry: %m = getelementptr inbounds %struct.t, %struct.t* %p, i32 0, i32 0 %0 = load atomic i32*, i32** %m acquire, align 4, !tbaa !1 store volatile i32 %v, i32* %0, align 4, !tbaa !6 %1 = load atomic i32*, i32** %m acquire, align 4, !tbaa !1 store volatile i32 %v, i32* %1, align 4, !tbaa !6 ret void } attributes #0 = { norecurse nounwind } !1 = !{!2, !3, i64 0} !2 = !{!"", !3, i64 0} !3 = !{!"any pointer", !4, i64 0} !4 = !{!"omnipotent char", !5, i64 0} !5 = !{!"Simple C/C++ TBAA"} !6 = !{!7, !7, i64 0} !7 = !{!"int", !4, i64 0}