[ORC] Guarantee unique JITDylib names in lli, add usage notes to createJITDylib.

JITDylibs should have unique names. This patch adds code to lli to respect this
invariant (by refering to the exist JITDylib if a -jd <name> option is specified
more than once). It also adds usage notes to the doxygen comment for
createJITDylib method in ExecutionSession and LLJIT.

http://llvm.org/PR41937

llvm-svn: 361322

1 files changed, 4 insertions, 2 deletions

diff --git a/llvm/tools/lli/lli.cpp b/llvm/tools/lli/lli.cpp
index a44b7437f70..fb6cf6ff915 100644
--- a/llvm/tools/lli/lli.cpp
+++ b/llvm/tools/lli/lli.cpp
@@ -821,8 +821,10 @@ int runOrcLazyJIT(const char *ProgName) {
     IdxToDylib[0] = &J->getMainJITDylib();
     for (auto JDItr = JITDylibs.begin(), JDEnd = JITDylibs.end();
          JDItr != JDEnd; ++JDItr) {
-      IdxToDylib[JITDylibs.getPosition(JDItr - JITDylibs.begin())] =
-          &J->createJITDylib(*JDItr);
+      orc::JITDylib *JD = J->getJITDylibByName(*JDItr);
+      if (!JD)
+        JD = &J->createJITDylib(*JDItr);
+      IdxToDylib[JITDylibs.getPosition(JDItr - JITDylibs.begin())] = JD;
     }
 
     for (auto EMItr = ExtraModules.begin(), EMEnd = ExtraModules.end();