diff --git a/hpvm/lib/Transforms/DFG2LLVM_NVPTX/DFG2LLVM_NVPTX.cpp b/hpvm/lib/Transforms/DFG2LLVM_NVPTX/DFG2LLVM_NVPTX.cpp
index 50f35399c59d997af7e0f7ad46f74832bf829124..8a36e3b8af5c031715d1e341f3ac166501c0a5b9 100644
--- a/hpvm/lib/Transforms/DFG2LLVM_NVPTX/DFG2LLVM_NVPTX.cpp
+++ b/hpvm/lib/Transforms/DFG2LLVM_NVPTX/DFG2LLVM_NVPTX.cpp
@@ -264,11 +264,13 @@ void CGT_NVPTX::initRuntimeAPI() {
   assert(LLVM_SRC_ROOT != NULL && "Define LLVM_SRC_ROOT environment variable!");
 
   Twine llvmSrcRoot = LLVM_SRC_ROOT;
-  Twine runtimeAPI = llvmSrcRoot + "/../build/tools/hpvm/projects/visc-rt/visc-rt.ll";
+  Twine runtimeAPI = llvmSrcRoot + "/../build/tools/hpvm/projects/visc-rt/visc-rt.bc";
 
   runtimeModule = parseIRFile(runtimeAPI.str(), Err, M.getContext());
-  if(runtimeModule == nullptr)
-    DEBUG(errs() << Err.getMessage());
+  if(runtimeModule == nullptr) {
+    DEBUG(errs() << Err.getMessage() << " " << runtimeAPI << "\n");
+    assert(false && "couldn't parse runtime");
+  }
   else
     DEBUG(errs() << "Successfully loaded visc-rt API module\n");
 
diff --git a/hpvm/lib/Transforms/GenVISC/GenVISC.cpp b/hpvm/lib/Transforms/GenVISC/GenVISC.cpp
index 1b4425459e1604894a7a4c26f1931b6de66022ba..cc505415396b4a0441d5a5bfe0cf58adc945b9f8 100644
--- a/hpvm/lib/Transforms/GenVISC/GenVISC.cpp
+++ b/hpvm/lib/Transforms/GenVISC/GenVISC.cpp
@@ -266,13 +266,15 @@ bool GenVISC::runOnModule(Module &M) {
          "Define LLVM_SRC_ROOT environment variable!");
 
   Twine llvmSrcRoot = LLVM_SRC_ROOT;
-  Twine runtimeAPI = llvmSrcRoot + "/../build/tools/hpvm/projects/visc-rt/visc-rt.ll";
+  Twine runtimeAPI = llvmSrcRoot + "/../build/tools/hpvm/projects/visc-rt/visc-rt.bc";
   errs() << llvmSrcRoot << "\n";
 
   std::unique_ptr<Module> runtimeModule = parseIRFile(runtimeAPI.str(), Err, M.getContext());
 
-  if(runtimeModule == NULL)
-    DEBUG(errs() << Err.getMessage());
+  if(runtimeModule == NULL) {
+    DEBUG(errs() << Err.getMessage() << " " << runtimeAPI << "\n");
+    assert(false && "couldn't parse runtime");
+  }
   else
     DEBUG(errs() << "Successfully loaded visc-rt API module\n");