Loose Type Analysis for Floating Point Add (rust-lang#828)

* Loose type analysis for float add

Author: wsmoses

enzyme/Enzyme/GradientUtils.h

@@ -2186,6 +2186,14 @@ class DiffeGradientUtils final : public GradientUtils {
     assert(dif->getType() == old->getType());
     Value *res = nullptr;
     if (old->getType()->isIntOrIntVectorTy()) {
+      if (!addingType) {
+        if (looseTypeAnalysis) {
+          if (old->getType()->isIntegerTy(64))
+            addingType = Type::getDoubleTy(old->getContext());
+          else if (old->getType()->isIntegerTy(32))
+            addingType = Type::getFloatTy(old->getContext());
+        }
+      }
       if (!addingType) {
         llvm::errs() << "module: " << *oldFunc->getParent() << "\n";
         llvm::errs() << "oldFunc: " << *oldFunc << "\n";