Add a const lookup routine to get a BlockAddress constant if there is

one, but not create one. This is useful in the verifier when we want to
query the constant if it exists but not create one. To be used in an
upcoming commit.

llvm-svn: 199568

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/lib/IR/Constants.cpp b/llvm/lib/IR/Constants.cpp
index 1f6f5ac4270..ecd2cfd9fd1 100644
--- a/llvm/lib/IR/Constants.cpp
+++ b/llvm/lib/IR/Constants.cpp
@@ -1375,6 +1375,17 @@ BlockAddress::BlockAddress(Function *F, BasicBlock *BB)
   BB->AdjustBlockAddressRefCount(1);
 }
 
+BlockAddress *BlockAddress::lookup(const BasicBlock *BB) {
+  if (!BB->hasAddressTaken())
+    return 0;
+
+  const Function *F = BB->getParent();
+  assert(F != 0 && "Block must have a parent");
+  BlockAddress *BA =
+      F->getContext().pImpl->BlockAddresses.lookup(std::make_pair(F, BB));
+  assert(BA && "Refcount and block address map disagree!");
+  return BA;
+}
 
 // destroyConstant - Remove the constant from the constant table.
 //