//===- LazyCallGraphTest.cpp - Unit tests for the lazy CG analysis --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// #include "llvm/Analysis/LazyCallGraph.h" #include "llvm/AsmParser/Parser.h" #include "llvm/IR/Function.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Module.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/SourceMgr.h" #include "gtest/gtest.h" #include using namespace llvm; namespace { std::unique_ptr parseAssembly(LLVMContext &Context, const char *Assembly) { SMDiagnostic Error; std::unique_ptr M = parseAssemblyString(Assembly, Error, Context); std::string ErrMsg; raw_string_ostream OS(ErrMsg); Error.print("", OS); // A failure here means that the test itself is buggy. if (!M) report_fatal_error(OS.str().c_str()); return M; } /* IR forming a call graph with a diamond of triangle-shaped SCCs: d1 / \ d3--d2 / \ b1 c1 / \ / \ b3--b2 c3--c2 \ / a1 / \ a3--a2 All call edges go up between SCCs, and clockwise around the SCC. */ static const char DiamondOfTriangles[] = "define void @a1() {\n" "entry:\n" " call void @a2()\n" " call void @b2()\n" " call void @c3()\n" " ret void\n" "}\n" "define void @a2() {\n" "entry:\n" " call void @a3()\n" " ret void\n" "}\n" "define void @a3() {\n" "entry:\n" " call void @a1()\n" " ret void\n" "}\n" "define void @b1() {\n" "entry:\n" " call void @b2()\n" " call void @d3()\n" " ret void\n" "}\n" "define void @b2() {\n" "entry:\n" " call void @b3()\n" " ret void\n" "}\n" "define void @b3() {\n" "entry:\n" " call void @b1()\n" " ret void\n" "}\n" "define void @c1() {\n" "entry:\n" " call void @c2()\n" " call void @d2()\n" " ret void\n" "}\n" "define void @c2() {\n" "entry:\n" " call void @c3()\n" " ret void\n" "}\n" "define void @c3() {\n" "entry:\n" " call void @c1()\n" " ret void\n" "}\n" "define void @d1() {\n" "entry:\n" " call void @d2()\n" " ret void\n" "}\n" "define void @d2() {\n" "entry:\n" " call void @d3()\n" " ret void\n" "}\n" "define void @d3() {\n" "entry:\n" " call void @d1()\n" " ret void\n" "}\n"; TEST(LazyCallGraphTest, BasicGraphFormation) { LLVMContext Context; std::unique_ptr M = parseAssembly(Context, DiamondOfTriangles); LazyCallGraph CG(*M); // The order of the entry nodes should be stable w.r.t. the source order of // the IR, and everything in our module is an entry node, so just directly // build variables for each node. auto I = CG.begin(); LazyCallGraph::Node &A1 = (I++)->getNode(CG); EXPECT_EQ("a1", A1.getFunction().getName()); LazyCallGraph::Node &A2 = (I++)->getNode(CG); EXPECT_EQ("a2", A2.getFunction().getName()); LazyCallGraph::Node &A3 = (I++)->getNode(CG); EXPECT_EQ("a3", A3.getFunction().getName()); LazyCallGraph::Node &B1 = (I++)->getNode(CG); EXPECT_EQ("b1", B1.getFunction().getName()); LazyCallGraph::Node &B2 = (I++)->getNode(CG); EXPECT_EQ("b2", B2.getFunction().getName()); LazyCallGraph::Node &B3 = (I++)->getNode(CG); EXPECT_EQ("b3", B3.getFunction().getName()); LazyCallGraph::Node &C1 = (I++)->getNode(CG); EXPECT_EQ("c1", C1.getFunction().getName()); LazyCallGraph::Node &C2 = (I++)->getNode(CG); EXPECT_EQ("c2", C2.getFunction().getName()); LazyCallGraph::Node &C3 = (I++)->getNode(CG); EXPECT_EQ("c3", C3.getFunction().getName()); LazyCallGraph::Node &D1 = (I++)->getNode(CG); EXPECT_EQ("d1", D1.getFunction().getName()); LazyCallGraph::Node &D2 = (I++)->getNode(CG); EXPECT_EQ("d2", D2.getFunction().getName()); LazyCallGraph::Node &D3 = (I++)->getNode(CG); EXPECT_EQ("d3", D3.getFunction().getName()); EXPECT_EQ(CG.end(), I); // Build vectors and sort them for the rest of the assertions to make them // independent of order. std::vector Nodes; for (LazyCallGraph::Edge &E : A1) Nodes.push_back(E.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ("a2", Nodes[0]); EXPECT_EQ("b2", Nodes[1]); EXPECT_EQ("c3", Nodes[2]); Nodes.clear(); EXPECT_EQ(A2.end(), std::next(A2.begin())); EXPECT_EQ("a3", A2.begin()->getFunction().getName()); EXPECT_EQ(A3.end(), std::next(A3.begin())); EXPECT_EQ("a1", A3.begin()->getFunction().getName()); for (LazyCallGraph::Edge &E : B1) Nodes.push_back(E.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ("b2", Nodes[0]); EXPECT_EQ("d3", Nodes[1]); Nodes.clear(); EXPECT_EQ(B2.end(), std::next(B2.begin())); EXPECT_EQ("b3", B2.begin()->getFunction().getName()); EXPECT_EQ(B3.end(), std::next(B3.begin())); EXPECT_EQ("b1", B3.begin()->getFunction().getName()); for (LazyCallGraph::Edge &E : C1) Nodes.push_back(E.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ("c2", Nodes[0]); EXPECT_EQ("d2", Nodes[1]); Nodes.clear(); EXPECT_EQ(C2.end(), std::next(C2.begin())); EXPECT_EQ("c3", C2.begin()->getFunction().getName()); EXPECT_EQ(C3.end(), std::next(C3.begin())); EXPECT_EQ("c1", C3.begin()->getFunction().getName()); EXPECT_EQ(D1.end(), std::next(D1.begin())); EXPECT_EQ("d2", D1.begin()->getFunction().getName()); EXPECT_EQ(D2.end(), std::next(D2.begin())); EXPECT_EQ("d3", D2.begin()->getFunction().getName()); EXPECT_EQ(D3.end(), std::next(D3.begin())); EXPECT_EQ("d1", D3.begin()->getFunction().getName()); // Now lets look at the RefSCCs and SCCs. auto J = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &D = *J++; ASSERT_EQ(1, D.size()); for (LazyCallGraph::Node &N : *D.begin()) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("d1", Nodes[0]); EXPECT_EQ("d2", Nodes[1]); EXPECT_EQ("d3", Nodes[2]); Nodes.clear(); EXPECT_FALSE(D.isParentOf(D)); EXPECT_FALSE(D.isChildOf(D)); EXPECT_FALSE(D.isAncestorOf(D)); EXPECT_FALSE(D.isDescendantOf(D)); LazyCallGraph::RefSCC &C = *J++; ASSERT_EQ(1, C.size()); for (LazyCallGraph::Node &N : *C.begin()) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("c1", Nodes[0]); EXPECT_EQ("c2", Nodes[1]); EXPECT_EQ("c3", Nodes[2]); Nodes.clear(); EXPECT_TRUE(C.isParentOf(D)); EXPECT_FALSE(C.isChildOf(D)); EXPECT_TRUE(C.isAncestorOf(D)); EXPECT_FALSE(C.isDescendantOf(D)); LazyCallGraph::RefSCC &B = *J++; ASSERT_EQ(1, B.size()); for (LazyCallGraph::Node &N : *B.begin()) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("b1", Nodes[0]); EXPECT_EQ("b2", Nodes[1]); EXPECT_EQ("b3", Nodes[2]); Nodes.clear(); EXPECT_TRUE(B.isParentOf(D)); EXPECT_FALSE(B.isChildOf(D)); EXPECT_TRUE(B.isAncestorOf(D)); EXPECT_FALSE(B.isDescendantOf(D)); EXPECT_FALSE(B.isAncestorOf(C)); EXPECT_FALSE(C.isAncestorOf(B)); LazyCallGraph::RefSCC &A = *J++; ASSERT_EQ(1, A.size()); for (LazyCallGraph::Node &N : *A.begin()) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("a1", Nodes[0]); EXPECT_EQ("a2", Nodes[1]); EXPECT_EQ("a3", Nodes[2]); Nodes.clear(); EXPECT_TRUE(A.isParentOf(B)); EXPECT_TRUE(A.isParentOf(C)); EXPECT_FALSE(A.isParentOf(D)); EXPECT_TRUE(A.isAncestorOf(B)); EXPECT_TRUE(A.isAncestorOf(C)); EXPECT_TRUE(A.isAncestorOf(D)); EXPECT_EQ(CG.postorder_ref_scc_end(), J); } static Function &lookupFunction(Module &M, StringRef Name) { for (Function &F : M) if (F.getName() == Name) return F; report_fatal_error("Couldn't find function!"); } TEST(LazyCallGraphTest, BasicGraphMutation) { LLVMContext Context; std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b()\n" " call void @c()\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); LazyCallGraph::Node &A = CG.get(lookupFunction(*M, "a")); LazyCallGraph::Node &B = CG.get(lookupFunction(*M, "b")); EXPECT_EQ(2, std::distance(A.begin(), A.end())); EXPECT_EQ(0, std::distance(B.begin(), B.end())); CG.insertEdge(B, lookupFunction(*M, "c"), LazyCallGraph::Edge::Call); EXPECT_EQ(1, std::distance(B.begin(), B.end())); LazyCallGraph::Node &C = B.begin()->getNode(CG); EXPECT_EQ(0, std::distance(C.begin(), C.end())); CG.insertEdge(C, B.getFunction(), LazyCallGraph::Edge::Call); EXPECT_EQ(1, std::distance(C.begin(), C.end())); EXPECT_EQ(&B, C.begin()->getNode()); CG.insertEdge(C, C.getFunction(), LazyCallGraph::Edge::Call); EXPECT_EQ(2, std::distance(C.begin(), C.end())); EXPECT_EQ(&B, C.begin()->getNode()); EXPECT_EQ(&C, std::next(C.begin())->getNode()); CG.removeEdge(C, B.getFunction()); EXPECT_EQ(1, std::distance(C.begin(), C.end())); EXPECT_EQ(&C, C.begin()->getNode()); CG.removeEdge(C, C.getFunction()); EXPECT_EQ(0, std::distance(C.begin(), C.end())); CG.removeEdge(B, C.getFunction()); EXPECT_EQ(0, std::distance(B.begin(), B.end())); } TEST(LazyCallGraphTest, InnerSCCFormation) { LLVMContext Context; std::unique_ptr M = parseAssembly(Context, DiamondOfTriangles); LazyCallGraph CG(*M); // Now mutate the graph to connect every node into a single RefSCC to ensure // that our inner SCC formation handles the rest. CG.insertEdge(lookupFunction(*M, "d1"), lookupFunction(*M, "a1"), LazyCallGraph::Edge::Ref); // Build vectors and sort them for the rest of the assertions to make them // independent of order. std::vector Nodes; // We should build a single RefSCC for the entire graph. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); // Now walk the four SCCs which should be in post-order. auto J = RC.begin(); LazyCallGraph::SCC &D = *J++; for (LazyCallGraph::Node &N : D) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("d1", Nodes[0]); EXPECT_EQ("d2", Nodes[1]); EXPECT_EQ("d3", Nodes[2]); Nodes.clear(); LazyCallGraph::SCC &B = *J++; for (LazyCallGraph::Node &N : B) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("b1", Nodes[0]); EXPECT_EQ("b2", Nodes[1]); EXPECT_EQ("b3", Nodes[2]); Nodes.clear(); LazyCallGraph::SCC &C = *J++; for (LazyCallGraph::Node &N : C) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("c1", Nodes[0]); EXPECT_EQ("c2", Nodes[1]); EXPECT_EQ("c3", Nodes[2]); Nodes.clear(); LazyCallGraph::SCC &A = *J++; for (LazyCallGraph::Node &N : A) Nodes.push_back(N.getFunction().getName()); std::sort(Nodes.begin(), Nodes.end()); EXPECT_EQ(3u, Nodes.size()); EXPECT_EQ("a1", Nodes[0]); EXPECT_EQ("a2", Nodes[1]); EXPECT_EQ("a3", Nodes[2]); Nodes.clear(); EXPECT_EQ(RC.end(), J); } TEST(LazyCallGraphTest, MultiArmSCC) { LLVMContext Context; // Two interlocking cycles. The really useful thing about this SCC is that it // will require Tarjan's DFS to backtrack and finish processing all of the // children of each node in the SCC. Since this involves call edges, both // Tarjan implementations will have to successfully navigate the structure. std::unique_ptr M = parseAssembly(Context, "define void @f1() {\n" "entry:\n" " call void @f2()\n" " call void @f4()\n" " ret void\n" "}\n" "define void @f2() {\n" "entry:\n" " call void @f3()\n" " ret void\n" "}\n" "define void @f3() {\n" "entry:\n" " call void @f1()\n" " ret void\n" "}\n" "define void @f4() {\n" "entry:\n" " call void @f5()\n" " ret void\n" "}\n" "define void @f5() {\n" "entry:\n" " call void @f1()\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &N1 = *CG.lookup(lookupFunction(*M, "f1")); LazyCallGraph::Node &N2 = *CG.lookup(lookupFunction(*M, "f2")); LazyCallGraph::Node &N3 = *CG.lookup(lookupFunction(*M, "f3")); LazyCallGraph::Node &N4 = *CG.lookup(lookupFunction(*M, "f4")); LazyCallGraph::Node &N5 = *CG.lookup(lookupFunction(*M, "f4")); EXPECT_EQ(&RC, CG.lookupRefSCC(N1)); EXPECT_EQ(&RC, CG.lookupRefSCC(N2)); EXPECT_EQ(&RC, CG.lookupRefSCC(N3)); EXPECT_EQ(&RC, CG.lookupRefSCC(N4)); EXPECT_EQ(&RC, CG.lookupRefSCC(N5)); ASSERT_EQ(1, RC.size()); LazyCallGraph::SCC &C = *RC.begin(); EXPECT_EQ(&C, CG.lookupSCC(N1)); EXPECT_EQ(&C, CG.lookupSCC(N2)); EXPECT_EQ(&C, CG.lookupSCC(N3)); EXPECT_EQ(&C, CG.lookupSCC(N4)); EXPECT_EQ(&C, CG.lookupSCC(N5)); } TEST(LazyCallGraphTest, OutgoingEdgeMutation) { LLVMContext Context; std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b()\n" " call void @c()\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " call void @d()\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " call void @d()\n" " ret void\n" "}\n" "define void @d() {\n" "entry:\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. for (LazyCallGraph::RefSCC &RC : CG.postorder_ref_sccs()) (void)RC; LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); LazyCallGraph::Node &D = *CG.lookup(lookupFunction(*M, "d")); LazyCallGraph::SCC &AC = *CG.lookupSCC(A); LazyCallGraph::SCC &BC = *CG.lookupSCC(B); LazyCallGraph::SCC &CC = *CG.lookupSCC(C); LazyCallGraph::SCC &DC = *CG.lookupSCC(D); LazyCallGraph::RefSCC &ARC = *CG.lookupRefSCC(A); LazyCallGraph::RefSCC &BRC = *CG.lookupRefSCC(B); LazyCallGraph::RefSCC &CRC = *CG.lookupRefSCC(C); LazyCallGraph::RefSCC &DRC = *CG.lookupRefSCC(D); EXPECT_TRUE(ARC.isParentOf(BRC)); EXPECT_TRUE(ARC.isParentOf(CRC)); EXPECT_FALSE(ARC.isParentOf(DRC)); EXPECT_TRUE(ARC.isAncestorOf(DRC)); EXPECT_FALSE(DRC.isChildOf(ARC)); EXPECT_TRUE(DRC.isDescendantOf(ARC)); EXPECT_TRUE(DRC.isChildOf(BRC)); EXPECT_TRUE(DRC.isChildOf(CRC)); EXPECT_EQ(2, std::distance(A.begin(), A.end())); ARC.insertOutgoingEdge(A, D, LazyCallGraph::Edge::Call); EXPECT_EQ(3, std::distance(A.begin(), A.end())); const LazyCallGraph::Edge &NewE = A[D]; EXPECT_TRUE(NewE); EXPECT_TRUE(NewE.isCall()); EXPECT_EQ(&D, NewE.getNode()); // Only the parent and child tests sholud have changed. The rest of the graph // remains the same. EXPECT_TRUE(ARC.isParentOf(DRC)); EXPECT_TRUE(ARC.isAncestorOf(DRC)); EXPECT_TRUE(DRC.isChildOf(ARC)); EXPECT_TRUE(DRC.isDescendantOf(ARC)); EXPECT_EQ(&AC, CG.lookupSCC(A)); EXPECT_EQ(&BC, CG.lookupSCC(B)); EXPECT_EQ(&CC, CG.lookupSCC(C)); EXPECT_EQ(&DC, CG.lookupSCC(D)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C)); EXPECT_EQ(&DRC, CG.lookupRefSCC(D)); ARC.switchOutgoingEdgeToRef(A, D); EXPECT_FALSE(NewE.isCall()); // Verify the graph remains the same. EXPECT_TRUE(ARC.isParentOf(DRC)); EXPECT_TRUE(ARC.isAncestorOf(DRC)); EXPECT_TRUE(DRC.isChildOf(ARC)); EXPECT_TRUE(DRC.isDescendantOf(ARC)); EXPECT_EQ(&AC, CG.lookupSCC(A)); EXPECT_EQ(&BC, CG.lookupSCC(B)); EXPECT_EQ(&CC, CG.lookupSCC(C)); EXPECT_EQ(&DC, CG.lookupSCC(D)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C)); EXPECT_EQ(&DRC, CG.lookupRefSCC(D)); ARC.switchOutgoingEdgeToCall(A, D); EXPECT_TRUE(NewE.isCall()); // Verify the graph remains the same. EXPECT_TRUE(ARC.isParentOf(DRC)); EXPECT_TRUE(ARC.isAncestorOf(DRC)); EXPECT_TRUE(DRC.isChildOf(ARC)); EXPECT_TRUE(DRC.isDescendantOf(ARC)); EXPECT_EQ(&AC, CG.lookupSCC(A)); EXPECT_EQ(&BC, CG.lookupSCC(B)); EXPECT_EQ(&CC, CG.lookupSCC(C)); EXPECT_EQ(&DC, CG.lookupSCC(D)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C)); EXPECT_EQ(&DRC, CG.lookupRefSCC(D)); ARC.removeOutgoingEdge(A, D); EXPECT_EQ(2, std::distance(A.begin(), A.end())); // Now the parent and child tests fail again but the rest remains the same. EXPECT_FALSE(ARC.isParentOf(DRC)); EXPECT_TRUE(ARC.isAncestorOf(DRC)); EXPECT_FALSE(DRC.isChildOf(ARC)); EXPECT_TRUE(DRC.isDescendantOf(ARC)); EXPECT_EQ(&AC, CG.lookupSCC(A)); EXPECT_EQ(&BC, CG.lookupSCC(B)); EXPECT_EQ(&CC, CG.lookupSCC(C)); EXPECT_EQ(&DC, CG.lookupSCC(D)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C)); EXPECT_EQ(&DRC, CG.lookupRefSCC(D)); } TEST(LazyCallGraphTest, IncomingEdgeInsertion) { LLVMContext Context; // We want to ensure we can add edges even across complex diamond graphs, so // we use the diamond of triangles graph defined above. The ascii diagram is // repeated here for easy reference. // // d1 | // / \ | // d3--d2 | // / \ | // b1 c1 | // / \ / \ | // b3--b2 c3--c2 | // \ / | // a1 | // / \ | // a3--a2 | // std::unique_ptr M = parseAssembly(Context, DiamondOfTriangles); LazyCallGraph CG(*M); // Force the graph to be fully expanded. for (LazyCallGraph::RefSCC &RC : CG.postorder_ref_sccs()) (void)RC; LazyCallGraph::Node &A1 = *CG.lookup(lookupFunction(*M, "a1")); LazyCallGraph::Node &A2 = *CG.lookup(lookupFunction(*M, "a2")); LazyCallGraph::Node &A3 = *CG.lookup(lookupFunction(*M, "a3")); LazyCallGraph::Node &B1 = *CG.lookup(lookupFunction(*M, "b1")); LazyCallGraph::Node &B2 = *CG.lookup(lookupFunction(*M, "b2")); LazyCallGraph::Node &B3 = *CG.lookup(lookupFunction(*M, "b3")); LazyCallGraph::Node &C1 = *CG.lookup(lookupFunction(*M, "c1")); LazyCallGraph::Node &C2 = *CG.lookup(lookupFunction(*M, "c2")); LazyCallGraph::Node &C3 = *CG.lookup(lookupFunction(*M, "c3")); LazyCallGraph::Node &D1 = *CG.lookup(lookupFunction(*M, "d1")); LazyCallGraph::Node &D2 = *CG.lookup(lookupFunction(*M, "d2")); LazyCallGraph::Node &D3 = *CG.lookup(lookupFunction(*M, "d3")); LazyCallGraph::RefSCC &ARC = *CG.lookupRefSCC(A1); LazyCallGraph::RefSCC &BRC = *CG.lookupRefSCC(B1); LazyCallGraph::RefSCC &CRC = *CG.lookupRefSCC(C1); LazyCallGraph::RefSCC &DRC = *CG.lookupRefSCC(D1); ASSERT_EQ(&ARC, CG.lookupRefSCC(A2)); ASSERT_EQ(&ARC, CG.lookupRefSCC(A3)); ASSERT_EQ(&BRC, CG.lookupRefSCC(B2)); ASSERT_EQ(&BRC, CG.lookupRefSCC(B3)); ASSERT_EQ(&CRC, CG.lookupRefSCC(C2)); ASSERT_EQ(&CRC, CG.lookupRefSCC(C3)); ASSERT_EQ(&DRC, CG.lookupRefSCC(D2)); ASSERT_EQ(&DRC, CG.lookupRefSCC(D3)); ASSERT_EQ(1, std::distance(D2.begin(), D2.end())); // Add an edge to make the graph: // // d1 | // / \ | // d3--d2---. | // / \ | | // b1 c1 | | // / \ / \ / | // b3--b2 c3--c2 | // \ / | // a1 | // / \ | // a3--a2 | auto MergedRCs = CRC.insertIncomingRefEdge(D2, C2); // Make sure we connected the nodes. for (LazyCallGraph::Edge E : D2) { if (E.getNode() == &D3) continue; EXPECT_EQ(&C2, E.getNode()); } // And marked the D ref-SCC as no longer valid. EXPECT_EQ(1u, MergedRCs.size()); EXPECT_EQ(&DRC, MergedRCs[0]); // Make sure we have the correct nodes in the SCC sets. EXPECT_EQ(&ARC, CG.lookupRefSCC(A1)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A2)); EXPECT_EQ(&ARC, CG.lookupRefSCC(A3)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B1)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B2)); EXPECT_EQ(&BRC, CG.lookupRefSCC(B3)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C1)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C2)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C3)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D1)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D2)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D3)); // And that ancestry tests have been updated. EXPECT_TRUE(ARC.isParentOf(CRC)); EXPECT_TRUE(BRC.isParentOf(CRC)); } TEST(LazyCallGraphTest, IncomingEdgeInsertionMidTraversal) { LLVMContext Context; // This is the same fundamental test as the previous, but we perform it // having only partially walked the RefSCCs of the graph. std::unique_ptr M = parseAssembly(Context, DiamondOfTriangles); LazyCallGraph CG(*M); // Walk the RefSCCs until we find the one containing 'c1'. auto I = CG.postorder_ref_scc_begin(), E = CG.postorder_ref_scc_end(); ASSERT_NE(I, E); LazyCallGraph::RefSCC &DRC = *I; ASSERT_NE(&DRC, nullptr); ++I; ASSERT_NE(I, E); LazyCallGraph::RefSCC &CRC = *I; ASSERT_NE(&CRC, nullptr); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "a1"))); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "a2"))); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "a3"))); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "b1"))); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "b2"))); ASSERT_EQ(nullptr, CG.lookup(lookupFunction(*M, "b3"))); LazyCallGraph::Node &C1 = *CG.lookup(lookupFunction(*M, "c1")); LazyCallGraph::Node &C2 = *CG.lookup(lookupFunction(*M, "c2")); LazyCallGraph::Node &C3 = *CG.lookup(lookupFunction(*M, "c3")); LazyCallGraph::Node &D1 = *CG.lookup(lookupFunction(*M, "d1")); LazyCallGraph::Node &D2 = *CG.lookup(lookupFunction(*M, "d2")); LazyCallGraph::Node &D3 = *CG.lookup(lookupFunction(*M, "d3")); ASSERT_EQ(&CRC, CG.lookupRefSCC(C1)); ASSERT_EQ(&CRC, CG.lookupRefSCC(C2)); ASSERT_EQ(&CRC, CG.lookupRefSCC(C3)); ASSERT_EQ(&DRC, CG.lookupRefSCC(D1)); ASSERT_EQ(&DRC, CG.lookupRefSCC(D2)); ASSERT_EQ(&DRC, CG.lookupRefSCC(D3)); ASSERT_EQ(1, std::distance(D2.begin(), D2.end())); auto MergedRCs = CRC.insertIncomingRefEdge(D2, C2); // Make sure we connected the nodes. for (LazyCallGraph::Edge E : D2) { if (E.getNode() == &D3) continue; EXPECT_EQ(&C2, E.getNode()); } // And marked the D ref-SCC as no longer valid. EXPECT_EQ(1u, MergedRCs.size()); EXPECT_EQ(&DRC, MergedRCs[0]); // Make sure we have the correct nodes in the RefSCCs. EXPECT_EQ(&CRC, CG.lookupRefSCC(C1)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C2)); EXPECT_EQ(&CRC, CG.lookupRefSCC(C3)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D1)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D2)); EXPECT_EQ(&CRC, CG.lookupRefSCC(D3)); // Check that we can form the last two RefSCCs now in a coherent way. ++I; EXPECT_NE(I, E); LazyCallGraph::RefSCC &BRC = *I; EXPECT_NE(&BRC, nullptr); EXPECT_EQ(&BRC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "b1")))); EXPECT_EQ(&BRC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "b2")))); EXPECT_EQ(&BRC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "b3")))); EXPECT_TRUE(BRC.isParentOf(CRC)); ++I; EXPECT_NE(I, E); LazyCallGraph::RefSCC &ARC = *I; EXPECT_NE(&ARC, nullptr); EXPECT_EQ(&ARC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "a1")))); EXPECT_EQ(&ARC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "a2")))); EXPECT_EQ(&ARC, CG.lookupRefSCC(*CG.lookup(lookupFunction(*M, "a3")))); EXPECT_TRUE(ARC.isParentOf(CRC)); ++I; EXPECT_EQ(E, I); } TEST(LazyCallGraphTest, InternalEdgeMutation) { LLVMContext Context; std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b()\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " call void @c()\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " call void @a()\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(&RC, CG.lookupRefSCC(B)); EXPECT_EQ(&RC, CG.lookupRefSCC(C)); EXPECT_EQ(1, RC.size()); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(A)); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(B)); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(C)); // Insert an edge from 'a' to 'c'. Nothing changes about the graph. RC.insertInternalRefEdge(A, C); EXPECT_EQ(2, std::distance(A.begin(), A.end())); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(&RC, CG.lookupRefSCC(B)); EXPECT_EQ(&RC, CG.lookupRefSCC(C)); EXPECT_EQ(1, RC.size()); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(A)); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(B)); EXPECT_EQ(&*RC.begin(), CG.lookupSCC(C)); // Switch the call edge from 'b' to 'c' to a ref edge. This will break the // call cycle and cause us to form more SCCs. The RefSCC will remain the same // though. RC.switchInternalEdgeToRef(B, C); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(&RC, CG.lookupRefSCC(B)); EXPECT_EQ(&RC, CG.lookupRefSCC(C)); auto J = RC.begin(); // The SCCs must be in *post-order* which means successors before // predecessors. At this point we have call edges from C to A and from A to // B. The only valid postorder is B, A, C. EXPECT_EQ(&*J++, CG.lookupSCC(B)); EXPECT_EQ(&*J++, CG.lookupSCC(A)); EXPECT_EQ(&*J++, CG.lookupSCC(C)); EXPECT_EQ(RC.end(), J); // Test turning the ref edge from A to C into a call edge. This will form an // SCC out of A and C. Since we previously had a call edge from C to A, the // C SCC should be preserved and have A merged into it while the A SCC should // be invalidated. LazyCallGraph::SCC &AC = *CG.lookupSCC(A); LazyCallGraph::SCC &CC = *CG.lookupSCC(C); auto InvalidatedSCCs = RC.switchInternalEdgeToCall(A, C); ASSERT_EQ(1u, InvalidatedSCCs.size()); EXPECT_EQ(&AC, InvalidatedSCCs[0]); EXPECT_EQ(2, CC.size()); EXPECT_EQ(&CC, CG.lookupSCC(A)); EXPECT_EQ(&CC, CG.lookupSCC(C)); J = RC.begin(); EXPECT_EQ(&*J++, CG.lookupSCC(B)); EXPECT_EQ(&*J++, CG.lookupSCC(C)); EXPECT_EQ(RC.end(), J); } TEST(LazyCallGraphTest, InternalEdgeRemoval) { LLVMContext Context; // A nice fully connected (including self-edges) RefSCC. std::unique_ptr M = parseAssembly( Context, "define void @a(i8** %ptr) {\n" "entry:\n" " store i8* bitcast (void(i8**)* @a to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @b to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @c to i8*), i8** %ptr\n" " ret void\n" "}\n" "define void @b(i8** %ptr) {\n" "entry:\n" " store i8* bitcast (void(i8**)* @a to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @b to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @c to i8*), i8** %ptr\n" " ret void\n" "}\n" "define void @c(i8** %ptr) {\n" "entry:\n" " store i8* bitcast (void(i8**)* @a to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @b to i8*), i8** %ptr\n" " store i8* bitcast (void(i8**)* @c to i8*), i8** %ptr\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(&RC, CG.lookupRefSCC(B)); EXPECT_EQ(&RC, CG.lookupRefSCC(C)); // Remove the edge from b -> a, which should leave the 3 functions still in // a single connected component because of a -> b -> c -> a. SmallVector NewRCs = RC.removeInternalRefEdge(B, A); EXPECT_EQ(0u, NewRCs.size()); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(&RC, CG.lookupRefSCC(B)); EXPECT_EQ(&RC, CG.lookupRefSCC(C)); // Remove the edge from c -> a, which should leave 'a' in the original RefSCC // and form a new RefSCC for 'b' and 'c'. NewRCs = RC.removeInternalRefEdge(C, A); EXPECT_EQ(1u, NewRCs.size()); EXPECT_EQ(&RC, CG.lookupRefSCC(A)); EXPECT_EQ(1, std::distance(RC.begin(), RC.end())); LazyCallGraph::RefSCC *RC2 = CG.lookupRefSCC(B); EXPECT_EQ(RC2, CG.lookupRefSCC(C)); EXPECT_EQ(RC2, NewRCs[0]); } TEST(LazyCallGraphTest, InternalCallEdgeToRef) { LLVMContext Context; // A nice fully connected (including self-edges) SCC (and RefSCC) std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @a()\n" " call void @b()\n" " call void @c()\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " call void @a()\n" " call void @b()\n" " call void @c()\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " call void @a()\n" " call void @b()\n" " call void @c()\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); EXPECT_EQ(1, RC.size()); LazyCallGraph::SCC &CallC = *RC.begin(); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); EXPECT_EQ(&CallC, CG.lookupSCC(A)); EXPECT_EQ(&CallC, CG.lookupSCC(B)); EXPECT_EQ(&CallC, CG.lookupSCC(C)); // Remove the call edge from b -> a to a ref edge, which should leave the // 3 functions still in a single connected component because of a -> b -> // c -> a. RC.switchInternalEdgeToRef(B, A); EXPECT_EQ(1, RC.size()); EXPECT_EQ(&CallC, CG.lookupSCC(A)); EXPECT_EQ(&CallC, CG.lookupSCC(B)); EXPECT_EQ(&CallC, CG.lookupSCC(C)); // Remove the edge from c -> a, which should leave 'a' in the original SCC // and form a new SCC for 'b' and 'c'. RC.switchInternalEdgeToRef(C, A); EXPECT_EQ(2, RC.size()); EXPECT_EQ(&CallC, CG.lookupSCC(A)); LazyCallGraph::SCC &BCallC = *CG.lookupSCC(B); EXPECT_NE(&BCallC, &CallC); EXPECT_EQ(&BCallC, CG.lookupSCC(C)); auto J = RC.find(CallC); EXPECT_EQ(&CallC, &*J); --J; EXPECT_EQ(&BCallC, &*J); EXPECT_EQ(RC.begin(), J); // Remove the edge from c -> b, which should leave 'b' in the original SCC // and form a new SCC for 'c'. It shouldn't change 'a's SCC. RC.switchInternalEdgeToRef(C, B); EXPECT_EQ(3, RC.size()); EXPECT_EQ(&CallC, CG.lookupSCC(A)); EXPECT_EQ(&BCallC, CG.lookupSCC(B)); LazyCallGraph::SCC &CCallC = *CG.lookupSCC(C); EXPECT_NE(&CCallC, &CallC); EXPECT_NE(&CCallC, &BCallC); J = RC.find(CallC); EXPECT_EQ(&CallC, &*J); --J; EXPECT_EQ(&BCallC, &*J); --J; EXPECT_EQ(&CCallC, &*J); EXPECT_EQ(RC.begin(), J); } TEST(LazyCallGraphTest, InternalRefEdgeToCall) { LLVMContext Context; // Basic tests for making a ref edge a call. This hits the basics of the // process only. std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b()\n" " call void @c()\n" " store void()* @d, void()** undef\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " store void()* @c, void()** undef\n" " call void @d()\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " store void()* @b, void()** undef\n" " call void @d()\n" " ret void\n" "}\n" "define void @d() {\n" "entry:\n" " store void()* @a, void()** undef\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); LazyCallGraph::Node &D = *CG.lookup(lookupFunction(*M, "d")); LazyCallGraph::SCC &AC = *CG.lookupSCC(A); LazyCallGraph::SCC &BC = *CG.lookupSCC(B); LazyCallGraph::SCC &CC = *CG.lookupSCC(C); LazyCallGraph::SCC &DC = *CG.lookupSCC(D); // Check the initial post-order. Note that B and C could be flipped here (and // in our mutation) without changing the nature of this test. ASSERT_EQ(4, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&BC, &RC[1]); EXPECT_EQ(&CC, &RC[2]); EXPECT_EQ(&AC, &RC[3]); // Switch the ref edge from A -> D to a call edge. This should have no // effect as it is already in postorder and no new cycles are formed. auto MergedCs = RC.switchInternalEdgeToCall(A, D); EXPECT_EQ(0u, MergedCs.size()); ASSERT_EQ(4, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&BC, &RC[1]); EXPECT_EQ(&CC, &RC[2]); EXPECT_EQ(&AC, &RC[3]); // Switch B -> C to a call edge. This doesn't form any new cycles but does // require reordering the SCCs. MergedCs = RC.switchInternalEdgeToCall(B, C); EXPECT_EQ(0u, MergedCs.size()); ASSERT_EQ(4, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&CC, &RC[1]); EXPECT_EQ(&BC, &RC[2]); EXPECT_EQ(&AC, &RC[3]); // Switch C -> B to a call edge. This forms a cycle and forces merging SCCs. MergedCs = RC.switchInternalEdgeToCall(C, B); ASSERT_EQ(1u, MergedCs.size()); EXPECT_EQ(&CC, MergedCs[0]); ASSERT_EQ(3, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&BC, &RC[1]); EXPECT_EQ(&AC, &RC[2]); EXPECT_EQ(2, BC.size()); EXPECT_EQ(&BC, CG.lookupSCC(B)); EXPECT_EQ(&BC, CG.lookupSCC(C)); } TEST(LazyCallGraphTest, InternalRefEdgeToCallNoCycleInterleaved) { LLVMContext Context; // Test for having a post-order prior to changing a ref edge to a call edge // with SCCs connecting to the source and connecting to the target, but not // connecting to both, interleaved between the source and target. This // ensures we correctly partition the range rather than simply moving one or // the other. std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b1()\n" " call void @c1()\n" " ret void\n" "}\n" "define void @b1() {\n" "entry:\n" " call void @c1()\n" " call void @b2()\n" " ret void\n" "}\n" "define void @c1() {\n" "entry:\n" " call void @b2()\n" " call void @c2()\n" " ret void\n" "}\n" "define void @b2() {\n" "entry:\n" " call void @c2()\n" " call void @b3()\n" " ret void\n" "}\n" "define void @c2() {\n" "entry:\n" " call void @b3()\n" " call void @c3()\n" " ret void\n" "}\n" "define void @b3() {\n" "entry:\n" " call void @c3()\n" " call void @d()\n" " ret void\n" "}\n" "define void @c3() {\n" "entry:\n" " store void()* @b1, void()** undef\n" " call void @d()\n" " ret void\n" "}\n" "define void @d() {\n" "entry:\n" " store void()* @a, void()** undef\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B1 = *CG.lookup(lookupFunction(*M, "b1")); LazyCallGraph::Node &B2 = *CG.lookup(lookupFunction(*M, "b2")); LazyCallGraph::Node &B3 = *CG.lookup(lookupFunction(*M, "b3")); LazyCallGraph::Node &C1 = *CG.lookup(lookupFunction(*M, "c1")); LazyCallGraph::Node &C2 = *CG.lookup(lookupFunction(*M, "c2")); LazyCallGraph::Node &C3 = *CG.lookup(lookupFunction(*M, "c3")); LazyCallGraph::Node &D = *CG.lookup(lookupFunction(*M, "d")); LazyCallGraph::SCC &AC = *CG.lookupSCC(A); LazyCallGraph::SCC &B1C = *CG.lookupSCC(B1); LazyCallGraph::SCC &B2C = *CG.lookupSCC(B2); LazyCallGraph::SCC &B3C = *CG.lookupSCC(B3); LazyCallGraph::SCC &C1C = *CG.lookupSCC(C1); LazyCallGraph::SCC &C2C = *CG.lookupSCC(C2); LazyCallGraph::SCC &C3C = *CG.lookupSCC(C3); LazyCallGraph::SCC &DC = *CG.lookupSCC(D); // Several call edges are initially present to force a particual post-order. // Remove them now, leaving an interleaved post-order pattern. RC.switchInternalEdgeToRef(B3, C3); RC.switchInternalEdgeToRef(C2, B3); RC.switchInternalEdgeToRef(B2, C2); RC.switchInternalEdgeToRef(C1, B2); RC.switchInternalEdgeToRef(B1, C1); // Check the initial post-order. We ensure this order with the extra edges // that are nuked above. ASSERT_EQ(8, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&C3C, &RC[1]); EXPECT_EQ(&B3C, &RC[2]); EXPECT_EQ(&C2C, &RC[3]); EXPECT_EQ(&B2C, &RC[4]); EXPECT_EQ(&C1C, &RC[5]); EXPECT_EQ(&B1C, &RC[6]); EXPECT_EQ(&AC, &RC[7]); // Switch C3 -> B1 to a call edge. This doesn't form any new cycles but does // require reordering the SCCs in the face of tricky internal node // structures. auto MergedCs = RC.switchInternalEdgeToCall(C3, B1); EXPECT_EQ(0u, MergedCs.size()); ASSERT_EQ(8, RC.size()); EXPECT_EQ(&DC, &RC[0]); EXPECT_EQ(&B3C, &RC[1]); EXPECT_EQ(&B2C, &RC[2]); EXPECT_EQ(&B1C, &RC[3]); EXPECT_EQ(&C3C, &RC[4]); EXPECT_EQ(&C2C, &RC[5]); EXPECT_EQ(&C1C, &RC[6]); EXPECT_EQ(&AC, &RC[7]); } TEST(LazyCallGraphTest, InternalRefEdgeToCallBothPartitionAndMerge) { LLVMContext Context; // Test for having a postorder where between the source and target are all // three kinds of other SCCs: // 1) One connected to the target only that have to be shifted below the // source. // 2) One connected to the source only that have to be shifted below the // target. // 3) One connected to both source and target that has to remain and get // merged away. // // To achieve this we construct a heavily connected graph to force // a particular post-order. Then we remove the forcing edges and connect // a cycle. // // Diagram for the graph we want on the left and the graph we use to force // the ordering on the right. Edges ponit down or right. // // A | A | // / \ | / \ | // B E | B \ | // |\ | | |\ | | // | D | | C-D-E | // | \| | | \| | // C F | \ F | // \ / | \ / | // G | G | // // And we form a cycle by connecting F to B. std::unique_ptr M = parseAssembly(Context, "define void @a() {\n" "entry:\n" " call void @b()\n" " call void @e()\n" " ret void\n" "}\n" "define void @b() {\n" "entry:\n" " call void @c()\n" " call void @d()\n" " ret void\n" "}\n" "define void @c() {\n" "entry:\n" " call void @d()\n" " call void @g()\n" " ret void\n" "}\n" "define void @d() {\n" "entry:\n" " call void @e()\n" " call void @f()\n" " ret void\n" "}\n" "define void @e() {\n" "entry:\n" " call void @f()\n" " ret void\n" "}\n" "define void @f() {\n" "entry:\n" " store void()* @b, void()** undef\n" " call void @g()\n" " ret void\n" "}\n" "define void @g() {\n" "entry:\n" " store void()* @a, void()** undef\n" " ret void\n" "}\n"); LazyCallGraph CG(*M); // Force the graph to be fully expanded. auto I = CG.postorder_ref_scc_begin(); LazyCallGraph::RefSCC &RC = *I++; EXPECT_EQ(CG.postorder_ref_scc_end(), I); LazyCallGraph::Node &A = *CG.lookup(lookupFunction(*M, "a")); LazyCallGraph::Node &B = *CG.lookup(lookupFunction(*M, "b")); LazyCallGraph::Node &C = *CG.lookup(lookupFunction(*M, "c")); LazyCallGraph::Node &D = *CG.lookup(lookupFunction(*M, "d")); LazyCallGraph::Node &E = *CG.lookup(lookupFunction(*M, "e")); LazyCallGraph::Node &F = *CG.lookup(lookupFunction(*M, "f")); LazyCallGraph::Node &G = *CG.lookup(lookupFunction(*M, "g")); LazyCallGraph::SCC &AC = *CG.lookupSCC(A); LazyCallGraph::SCC &BC = *CG.lookupSCC(B); LazyCallGraph::SCC &CC = *CG.lookupSCC(C); LazyCallGraph::SCC &DC = *CG.lookupSCC(D); LazyCallGraph::SCC &EC = *CG.lookupSCC(E); LazyCallGraph::SCC &FC = *CG.lookupSCC(F); LazyCallGraph::SCC &GC = *CG.lookupSCC(G); // Remove the extra edges that were used to force a particular post-order. RC.switchInternalEdgeToRef(C, D); RC.switchInternalEdgeToRef(D, E); // Check the initial post-order. We ensure this order with the extra edges // that are nuked above. ASSERT_EQ(7, RC.size()); EXPECT_EQ(&GC, &RC[0]); EXPECT_EQ(&FC, &RC[1]); EXPECT_EQ(&EC, &RC[2]); EXPECT_EQ(&DC, &RC[3]); EXPECT_EQ(&CC, &RC[4]); EXPECT_EQ(&BC, &RC[5]); EXPECT_EQ(&AC, &RC[6]); // Switch F -> B to a call edge. This merges B, D, and F into a single SCC, // and has to place the C and E SCCs on either side of it: // A A | // / \ / \ | // B E | E | // |\ | \ / | // | D | -> B | // | \| / \ | // C F C | | // \ / \ / | // G G | auto MergedCs = RC.switchInternalEdgeToCall(F, B); ASSERT_EQ(2u, MergedCs.size()); EXPECT_EQ(&FC, MergedCs[0]); EXPECT_EQ(&DC, MergedCs[1]); EXPECT_EQ(3, BC.size()); // And make sure the postorder was updated. ASSERT_EQ(5, RC.size()); EXPECT_EQ(&GC, &RC[0]); EXPECT_EQ(&CC, &RC[1]); EXPECT_EQ(&BC, &RC[2]); EXPECT_EQ(&EC, &RC[3]); EXPECT_EQ(&AC, &RC[4]); } }