diff --git a/lib/Transforms/IPO/MergeFunctions.cpp b/lib/Transforms/IPO/MergeFunctions.cpp index 2e3519eac6a..109cac7fece 100644 --- a/lib/Transforms/IPO/MergeFunctions.cpp +++ b/lib/Transforms/IPO/MergeFunctions.cpp @@ -1516,6 +1516,8 @@ void MergeFunctions::remove(Function *F) { void MergeFunctions::removeUsers(Value *V) { std::vector Worklist; Worklist.push_back(V); + SmallSet Visited; + Visited.insert(V); while (!Worklist.empty()) { Value *V = Worklist.back(); Worklist.pop_back(); @@ -1526,8 +1528,10 @@ void MergeFunctions::removeUsers(Value *V) { } else if (isa(U)) { // do nothing } else if (Constant *C = dyn_cast(U)) { - for (User *UU : C->users()) - Worklist.push_back(UU); + for (User *UU : C->users()) { + if (!Visited.insert(UU).second) + Worklist.push_back(UU); + } } } } diff --git a/test/Transforms/MergeFunc/self-referential-global.ll b/test/Transforms/MergeFunc/self-referential-global.ll new file mode 100644 index 00000000000..d3d1c62aa7f --- /dev/null +++ b/test/Transforms/MergeFunc/self-referential-global.ll @@ -0,0 +1,40 @@ +; RUN: opt -mergefunc -disable-output < %s + +; A linked list type and simple payload +%LL = type { %S, %LL* } +%S = type { void (%S*, i32)* } + +; Table refers to itself via GEP +@Table = internal global [3 x %LL] [%LL { %S { void (%S*, i32)* @B }, %LL* getelementptr inbounds ([3 x %LL], [3 x %LL]* @Table, i32 0, i32 0) }, %LL { %S { void (%S*, i32)* @A }, %LL* getelementptr inbounds ([3 x %LL], [3 x %LL]* @Table, i32 0, i32 0) }, %LL { %S { void (%S*, i32)* @A }, %LL* getelementptr inbounds ([3 x %LL], [3 x %LL]* @Table, i32 0, i32 0) }], align 16 + +; The body of this is irrelevant; it is long so that mergefunc doesn't skip it as a small function. +define internal void @A(%S* %self, i32 %a) { + %1 = add i32 %a, 32 + %2 = add i32 %1, 32 + %3 = add i32 %2, 32 + %4 = add i32 %3, 32 + %5 = add i32 %4, 32 + %6 = add i32 %5, 32 + %7 = add i32 %6, 32 + %8 = add i32 %7, 32 + %9 = add i32 %8, 32 + %10 = add i32 %9, 32 + %11 = add i32 %10, 32 + ret void +} + +define internal void @B(%S* %self, i32 %a) { + %1 = add i32 %a, 32 + %2 = add i32 %1, 32 + %3 = add i32 %2, 32 + %4 = add i32 %3, 32 + %5 = add i32 %4, 32 + %6 = add i32 %5, 32 + %7 = add i32 %6, 32 + %8 = add i32 %7, 32 + %9 = add i32 %8, 32 + %10 = add i32 %9, 32 + %11 = add i32 %10, 32 + ret void +} +