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
diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp
index 5cf0abc..789ced1 100644
--- a/lib/Transforms/Scalar/SCCP.cpp
+++ b/lib/Transforms/Scalar/SCCP.cpp
@@ -1749,6 +1749,13 @@
bool IPSCCP::runOnModule(Module &M) {
SCCPSolver Solver(getAnalysisIfAvailable<TargetData>());
+ // 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<Function*, 32> AddressTakenFunctions;
+
// Loop over all functions, marking arguments to those with their addresses
// taken or that are external as overdefined.
//
@@ -1764,9 +1771,13 @@
// 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 @@
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)