diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp index 5cf0abca4cc..789ced1fb92 100644 --- a/lib/Transforms/Scalar/SCCP.cpp +++ b/lib/Transforms/Scalar/SCCP.cpp @@ -1749,6 +1749,13 @@ static bool AddressIsTaken(const GlobalValue *GV) { bool IPSCCP::runOnModule(Module &M) { SCCPSolver Solver(getAnalysisIfAvailable()); + // AddressTakenFunctions - This set keeps track of the address-taken functions + // that are in the input. As IPSCCP runs through and simplifies code, + // functions that were address taken can end up losing their + // address-taken-ness. Because of this, we keep track of their addresses from + // the first pass so we can use them for the later simplification pass. + SmallPtrSet AddressTakenFunctions; + // Loop over all functions, marking arguments to those with their addresses // taken or that are external as overdefined. // @@ -1764,9 +1771,13 @@ bool IPSCCP::runOnModule(Module &M) { // If this function only has direct calls that we can see, we can track its // arguments and return value aggressively, and can assume it is not called // unless we see evidence to the contrary. - if (F->hasLocalLinkage() && !AddressIsTaken(F)) { - Solver.AddArgumentTrackedFunction(F); - continue; + if (F->hasLocalLinkage()) { + if (AddressIsTaken(F)) + AddressTakenFunctions.insert(F); + else { + Solver.AddArgumentTrackedFunction(F); + continue; + } } // Assume the function is called. @@ -1951,7 +1962,7 @@ bool IPSCCP::runOnModule(Module &M) { continue; // We can only do this if we know that nothing else can call the function. - if (!F->hasLocalLinkage() || AddressIsTaken(F)) + if (!F->hasLocalLinkage() || AddressTakenFunctions.count(F)) continue; for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) diff --git a/test/Transforms/SCCP/ipsccp-addr-taken.ll b/test/Transforms/SCCP/ipsccp-addr-taken.ll new file mode 100644 index 00000000000..c6572fa5d14 --- /dev/null +++ b/test/Transforms/SCCP/ipsccp-addr-taken.ll @@ -0,0 +1,28 @@ +; RUN: opt %s -ipsccp -S | FileCheck %s +; PR7876 +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" +target triple = "x86_64-apple-darwin10.0.0" + +define internal i32 @foo() nounwind noinline ssp { +entry: + ret i32 0 +; CHECK: @foo +; CHECK: entry: +; CHECK: ret i32 0 +} + +declare i32 @bar() + +define internal i32 @test(i32 %c) nounwind noinline ssp { +bb: + %tmp1 = icmp ne i32 %c, 0 ; [#uses=1] + %tmp2 = select i1 %tmp1, i32 ()* @foo, i32 ()* @bar ; [#uses=1] + %tmp3 = tail call i32 %tmp2() nounwind ; [#uses=1] + ret i32 %tmp3 +} + +define i32 @main() nounwind ssp { +bb: + %tmp = tail call i32 @test(i32 1) ; [#uses=1] + ret i32 %tmp +}