[MCJIT] Fix PR20656 by teaching MCJIT to honor ExecutionEngine's global mapping.

This is important for users of the C API who can't supply custom symbol
resolvers yet.

llvm-svn: 243589

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 492478d..c201f39 100644
--- a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -270,6 +270,12 @@ void MCJIT::finalizeModule(Module *M) {
 RuntimeDyld::SymbolInfo MCJIT::findExistingSymbol(const std::string &Name) {
   SmallString<128> FullName;
   Mangler::getNameWithPrefix(FullName, Name, getDataLayout());
+
+  if (void *Addr = getPointerToGlobalIfAvailable(FullName))
+    return RuntimeDyld::SymbolInfo(static_cast<uint64_t>(
+                                     reinterpret_cast<uintptr_t>(Addr)),
+                                   JITSymbolFlags::Exported);
+
   return Dyld.getSymbol(FullName);
 }