Fixing problems in lli's RemoteMemoryManager.

This fixes a problem from a previous check-in where a return value was omitted.

Previously the remote/stubs-remote.ll and remote/stubs-sm-pic.ll tests were reporting passes, but they should have been failing.  Those tests attempt to link against an external symbol and remote symbol resolution is not supported.  The old RemoteMemoryManager implementation resulted in local symbols being used for resolution and the child process crashed but the test didn't notice.  With this check-in remote symbol resolution fails, and so the test (correctly) fails.

llvm-svn: 192514

llvm/test/ExecutionEngine/MCJIT/remote/stubs-remote.ll

@@ -1,5 +1,6 @@
 ; RUN: %lli_mcjit -remote-mcjit -disable-lazy-compilation=false -mcjit-remote-process=lli-child-target %s
-; XFAIL:  mips
+; XFAIL: *
+; This test should fail until remote symbol resolution is supported.
 
 define i32 @main() nounwind {
 entry:

llvm/test/ExecutionEngine/MCJIT/remote/stubs-sm-pic.ll

@@ -1,5 +1,6 @@
 ; RUN: %lli_mcjit -remote-mcjit -disable-lazy-compilation=false -relocation-model=pic -code-model=small %s
-; XFAIL: mips, i686, i386, aarch64, arm
+; XFAIL: *
+; This function should fail until remote symbol resolution is supported.
 
 define i32 @main() nounwind {
 entry:

llvm/tools/lli/RemoteMemoryManager.h

@@ -78,7 +78,7 @@ public:
   // interface does support this, but clients must provide their own
   // mechanism for finding remote symbol addresses.  MCJIT will resolve
   // symbols from Modules it contains.
-  uint64_t getSymbolAddress(const std::string &Name) {}
+  uint64_t getSymbolAddress(const std::string &Name) { return 0; }
 
   void notifyObjectLoaded(ExecutionEngine *EE, const ObjectImage *Obj);
 

llvm/tools/lli/lli.cpp

@@ -398,18 +398,18 @@ int main(int argc, char **argv, char * const *envp) {
     return -1;
   }
 
-  // If the program doesn't explicitly call exit, we will need the Exit
-  // function later on to make an explicit call, so get the function now.
-  Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context),
-                                                    Type::getInt32Ty(Context),
-                                                    NULL);
-
   // Reset errno to zero on entry to main.
   errno = 0;
 
   int Result;
 
   if (!RemoteMCJIT) {
+    // If the program doesn't explicitly call exit, we will need the Exit
+    // function later on to make an explicit call, so get the function now.
+    Constant *Exit = Mod->getOrInsertFunction("exit", Type::getVoidTy(Context),
+                                                      Type::getInt32Ty(Context),
+                                                      NULL);
+
     // Run static constructors.
     if (UseMCJIT && !ForceInterpreter) {
       // Give MCJIT a chance to apply relocations and set page permissions.