Index: llvm/trunk/lib/Analysis/LazyCallGraph.cpp =================================================================== --- llvm/trunk/lib/Analysis/LazyCallGraph.cpp +++ llvm/trunk/lib/Analysis/LazyCallGraph.cpp @@ -172,6 +172,19 @@ addEdge(EntryEdges.Edges, EntryEdges.EdgeIndexMap, get(F), Edge::Ref); } + // Externally visible aliases of internal functions are also viable entry + // edges to the module. + for (auto &A : M.aliases()) { + if (A.hasLocalLinkage()) + continue; + if (Function* F = dyn_cast(A.getAliasee())) { + LLVM_DEBUG(dbgs() << " Adding '" << F->getName() + << "' with alias '" << A.getName() + << "' to entry set of the graph.\n"); + addEdge(EntryEdges.Edges, EntryEdges.EdgeIndexMap, get(*F), Edge::Ref); + } + } + // Now add entry nodes for functions reachable via initializers to globals. SmallVector Worklist; SmallPtrSet Visited; Index: llvm/trunk/test/Analysis/LazyCallGraph/alias.ll =================================================================== --- llvm/trunk/test/Analysis/LazyCallGraph/alias.ll +++ llvm/trunk/test/Analysis/LazyCallGraph/alias.ll @@ -0,0 +1,38 @@ +; RUN: opt -disable-output -passes=print-lcg %s 2>&1 | FileCheck %s +; +; Aliased function should be reachable in CGSCC. + +target triple = "x86_64-grtev4-linux-gnu" + +; CHECK: Edges in function: foo +; CHECK: Edges in function: bar +; CHECK: Edges in function: baz + +; CHECK: RefSCC with 1 call SCCs: +; CHECK-NEXT: SCC with 1 functions: +; CHECK-NEXT: bar + +; CHECK: RefSCC with 1 call SCCs: +; CHECK-NEXT: SCC with 1 functions: +; CHECK-NEXT: foo + +; CHECK-NOT: baz + +@alias1 = weak dso_local alias i8* (i8*), i8* (i8*)* @foo + +define dso_local i8* @foo(i8* %returned) { + ret i8* %returned +} + +@alias2 = weak dso_local alias i8* (i8*), i8* (i8*)* @bar + +define internal i8* @bar(i8* %returned) { + ret i8* %returned +} + +; Internal alias is not reachable. +@alias3 = internal alias i8* (i8*), i8* (i8*)* @baz + +define internal i8* @baz(i8* %returned) { + ret i8* %returned +}