Handle mark_dependence in ConstExpr

Author: meg-gupta

lib/SILOptimizer/Utils/ConstExpr.cpp

@@ -528,6 +528,9 @@ SymbolicValue ConstExprFunctionState::computeConstantValue(SILValue value) {
   if (auto *convertEscapeInst = dyn_cast<ConvertEscapeToNoEscapeInst>(value))
     return getConstantValue(convertEscapeInst->getOperand());
 
+  if (auto *mdi = dyn_cast<MarkDependenceInst>(value))
+    return getConstantValue(mdi->getValue());
+
   LLVM_DEBUG(llvm::dbgs() << "ConstExpr Unknown simple: " << *value << "\n");
 
   // Otherwise, we don't know how to handle this.