diff --git a/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp b/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
index 6b6f62e..daa7b7a 100644
--- a/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
@@ -18,6 +18,7 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/RegisterScavenging.h"
+#include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/MC/MCDwarf.h"
 
 using namespace llvm;
@@ -131,6 +132,12 @@
   if (StackSize == 0 && !MFI.adjustsStack())
     return;
 
+  // If the stack pointer has been marked as reserved, then produce an error if
+  // the frame requires stack allocation
+  if (STI.isRegisterReservedByUser(SPReg))
+    MF.getFunction().getContext().diagnose(DiagnosticInfoUnsupported{
+        MF.getFunction(), "Stack pointer required, but has been reserved."});
+
   uint64_t FirstSPAdjustAmount = getFirstSPAdjustAmount(MF);
   // Split the SP adjustment to reduce the offsets of callee saved spill.
   if (FirstSPAdjustAmount)
@@ -167,6 +174,10 @@
 
   // Generate new FP.
   if (hasFP(MF)) {
+    if (STI.isRegisterReservedByUser(FPReg))
+      MF.getFunction().getContext().diagnose(DiagnosticInfoUnsupported{
+          MF.getFunction(), "Frame pointer required, but has been reserved."});
+
     adjustReg(MBB, MBBI, DL, FPReg, SPReg,
               StackSize - RVFI->getVarArgsSaveSize(), MachineInstr::FrameSetup);