[RuntimeDyld] Track symbol visibility in RuntimeDyld.

RuntimeDyld symbol info previously consisted of just a Section/Offset pair. This
patch replaces that pair type with a SymbolInfo class that also tracks symbol
visibility. A new method, RuntimeDyld::getExportedSymbolLoadAddress, is
introduced which only returns a non-zero result for exported symbols. For
non-exported or non-existant symbols this method will return zero. The
RuntimeDyld::getSymbolAddress method retains its current behavior, returning
non-zero results for all symbols regardless of visibility.

No in-tree clients of RuntimeDyld are changed. The newly introduced
functionality will be used by the Orc APIs.

No test case: Since this patch doesn't modify the behavior for any in-tree
clients we don't have a good tool to test this with yet. Once Orc is in we can
use it to write regression tests that test these changes.

llvm-svn: 226341

1 files changed, 4 insertions, 3 deletions

diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
index 21893d2909e..2d3966270fc 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
@@ -64,11 +64,12 @@ RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
     symbol_iterator Symbol = RI->getSymbol();
     StringRef TargetName;
     Symbol->getName(TargetName);
-    SymbolTableMap::const_iterator SI =
+    RTDyldSymbolTable::const_iterator SI =
       GlobalSymbolTable.find(TargetName.data());
     if (SI != GlobalSymbolTable.end()) {
-      Value.SectionID = SI->second.first;
-      Value.Offset = SI->second.second + RE.Addend;
+      const auto &SymInfo = SI->second;
+      Value.SectionID = SymInfo.getSectionID();
+      Value.Offset = SymInfo.getOffset() + RE.Addend;
     } else {
       Value.SymbolName = TargetName.data();
       Value.Offset = RE.Addend;