2 files changed, 5 insertions, 2 deletions
diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc
index c294294580..fb150c3fa8 100644
--- a/compiler/optimizing/nodes.cc
+++ b/compiler/optimizing/nodes.cc
@@ -287,7 +287,10 @@ void HGraph::InsertConstant(HConstant* constant) {
 }
 
 HNullConstant* HGraph::GetNullConstant() {
-  if (cached_null_constant_ == nullptr) {
+  // For simplicity, don't bother reviving the cached null constant if it is
+  // not null and not in a block. Otherwise, we need to clear the instruction
+  // id and/or any invariants the graph is assuming when adding new instructions.
+  if ((cached_null_constant_ == nullptr) || (cached_null_constant_->GetBlock() == nullptr)) {
     cached_null_constant_ = new (arena_) HNullConstant();
     InsertConstant(cached_null_constant_);
   }
diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 5632434c0f..64d6023fba 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -342,9 +342,9 @@ static void RunOptimizations(HGraph* graph,
 
   HOptimization* optimizations[] = {
     &intrinsics,
-    &dce1,
     &fold1,
     &simplify1,
+    &dce1,
     &inliner,
     // BooleanSimplifier depends on the InstructionSimplifier removing redundant
     // suspend checks to recognize empty blocks.