Fix forward phi debug info (rust-lang#546)

Author: wsmoses

enzyme/Enzyme/AdjointGenerator.h

@@ -975,15 +975,15 @@ class AdjointGenerator
       BasicBlock *oBB = phi.getParent();
       BasicBlock *nBB = gutils->getNewFromOriginal(oBB);
 
-      IRBuilder<> diffeBuilder(nBB->getFirstNonPHI());
-      diffeBuilder.setFastMathFlags(getFast());
-
       IRBuilder<> phiBuilder(&phi);
       getForwardBuilder(phiBuilder);
+      phiBuilder.SetInsertPoint(
+          gutils->getNewFromOriginal(&phi)->getNextNode());
 
       Type *diffeType = gutils->getShadowType(phi.getType());
 
       auto newPhi = phiBuilder.CreatePHI(diffeType, 1, phi.getName() + "'");
+
       for (unsigned int i = 0; i < phi.getNumIncomingValues(); ++i) {
         auto val = phi.getIncomingValue(i);
         auto block = phi.getIncomingBlock(i);
@@ -1000,7 +1000,10 @@ class AdjointGenerator
         }
       }
 
+      IRBuilder<> diffeBuilder(nBB->getFirstNonPHI());
+      diffeBuilder.setFastMathFlags(getFast());
       setDiffe(&phi, newPhi, diffeBuilder);
+
       return;
     }
     }

enzyme/Enzyme/TypeAnalysis/TypeAnalysis.cpp

@@ -1315,6 +1315,7 @@ void TypeAnalyzer::visitStoreInst(StoreInst &I) {
 template <typename T>
 std::set<std::vector<T>> getSet(const std::vector<std::set<T>> &todo,
                                 size_t idx) {
+  assert(idx < todo.size());
   std::set<std::vector<T>> out;
   if (idx == 0) {
     for (auto val : todo[0]) {
@@ -1406,6 +1407,7 @@ void TypeAnalyzer::visitGetElementPtrInst(GetElementPtrInst &gep) {
     if (idnext.back().size() == 0)
       return;
   }
+  assert(idnext.size() != 0);
 
   TypeTree upTree;
   TypeTree downTree;