[llvm-commits] [llvm] r66050 - in /llvm/trunk/lib/ExecutionEngine/JIT: JIT.cpp JITEmitter.cpp

[Nate Begeman]

Author: sampo
Date: Wed Mar  4 13:10:38 2009
New Revision: 66050

URL: http://llvm.org/viewvc/llvm-project?rev=66050&view=rev
Log:
Fix a thinko in the JIT where the address of a GV was only recorded in the map
  on failure to resolve it.
Do not abort on failure to resolve an external symbol when using dlsym stubs,
  since the symbol may not be in the JIT's address space.  Just use 0.
Allow dlsym stubs to differentiate between GlobalVars and Functions.

Modified:
    llvm/trunk/lib/ExecutionEngine/JIT/JIT.cpp
    llvm/trunk/lib/ExecutionEngine/JIT/JITEmitter.cpp

Modified: llvm/trunk/lib/ExecutionEngine/JIT/JIT.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/JIT/JIT.cpp?rev=66050&r1=66049&r2=66050&view=diff

==============================================================================
--- llvm/trunk/lib/ExecutionEngine/JIT/JIT.cpp (original)
+++ llvm/trunk/lib/ExecutionEngine/JIT/JIT.cpp Wed Mar  4 13:10:38 2009
@@ -609,12 +609,12 @@
       return (void*)&__dso_handle;
 #endif
     Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(GV->getName().c_str());
-    if (Ptr == 0) {
+    if (Ptr == 0 && !areDlsymStubsEnabled()) {
       cerr << "Could not resolve external global address: "
            << GV->getName() << "\n";
       abort();
-    addGlobalMapping(GV, Ptr);
     }
+    addGlobalMapping(GV, Ptr);
   } else {
     // GlobalVariable's which are not "constant" will cause trouble in a server
     // situation. It's returned in the same block of memory as code which may

Modified: llvm/trunk/lib/ExecutionEngine/JIT/JITEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/JIT/JITEmitter.cpp?rev=66050&r1=66049&r2=66050&view=diff

==============================================================================
--- llvm/trunk/lib/ExecutionEngine/JIT/JITEmitter.cpp (original)
+++ llvm/trunk/lib/ExecutionEngine/JIT/JITEmitter.cpp Wed Mar  4 13:10:38 2009
@@ -1348,12 +1348,22 @@
   for (unsigned i = 0; i != GVs.size(); ++i)
     MCE->emitInt32(Offsets[i]);
   
-  // Emit the pointers
-  for (unsigned i = 0; i != GVs.size(); ++i)
+  // Emit the pointers.  Verify that they are at least 2-byte aligned, and set
+  // the low bit to 0 == GV, 1 == Function, so that the client code doing the
+  // relocation can write the relocated pointer at the appropriate place in
+  // the stub.
+  for (unsigned i = 0; i != GVs.size(); ++i) {
+    intptr_t Ptr = (intptr_t)Ptrs[i];
+    assert((Ptr & 1) == 0 && "Stub pointers must be at least 2-byte aligned!");
+    
+    if (isa<Function>(GVs[i]))
+      Ptr |= (intptr_t)1;
+           
     if (sizeof(void *) == 8)
-      MCE->emitInt64((intptr_t)Ptrs[i]);
+      MCE->emitInt64(Ptr);
     else
-      MCE->emitInt32((intptr_t)Ptrs[i]);
+      MCE->emitInt32(Ptr);
+  }
   
   // Emit the strings
   for (unsigned i = 0; i != GVs.size(); ++i)