Don't add shadow stack to debug calls.

After merging upstream LLVM, some yk langtester tests failed, due to extra
debug calls appearing in the AOT IR. Investigating this I noticed that we are
inserting shadowstack calculations before and after debug calls, which isn't
necessary since those calls are removed in the JIT IR anyway. Incidentally, this
also resolves the tests failures without changing (most of) them.

Author: ptersilie

llvm/lib/Transforms/Yk/ShadowStack.cpp

@@ -193,8 +193,11 @@ class YkShadowStack : public ModulePass {
               if (CI.getCalledFunction()->getName() ==
                   "llvm.experimental.stackmap") {
                 continue;
-              } else if (CI.getCalledFunction()->getName() ==
-                         "llvm.dbg.declare") {
+              }
+              if (CI.getCalledFunction()->getName() == "llvm.dbg.declare") {
+                continue;
+              }
+              if (CI.getCalledFunction()->getName() == "llvm.dbg.value") {
                 continue;
               }
             }

llvm/lib/Transforms/Yk/StackMaps.cpp

@@ -91,7 +91,7 @@ class YkStackmaps : public ModulePass {
         // Insert the stackmap call after (not before) the call instruction, so
         // the offset of the stackmap entry will record the instruction after
         // the call, which is where we want to continue after deoptimisation.
-        Bldr.SetInsertPoint(I->getNextNonDebugInstruction());
+        Bldr.SetInsertPoint(I->getNextNode());
       }
       Bldr.CreateCall(SMFunc->getFunctionType(), SMFunc,
                       ArrayRef<Value *>(Args));