From 1522ce9770567aeb67eae374c83fd0bdce949305 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Thu, 12 Aug 2010 22:25:23 +0000 Subject: fix PR7876: If ipsccp decides that a function's address is taken before it rewrites the code, we need to use that in the post-rewrite pass. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110962 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/SCCP.cpp | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'lib/Transforms/Scalar/SCCP.cpp') diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp index 5cf0abca4c..789ced1fb9 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) -- cgit v1.2.3