Index: mlir/include/mlir/Dialect/LLVMIR/LLVMOpBase.td
===================================================================
--- mlir/include/mlir/Dialect/LLVMIR/LLVMOpBase.td
+++ mlir/include/mlir/Dialect/LLVMIR/LLVMOpBase.td
@@ -66,6 +66,12 @@
     /// Returns `true` if the given type is compatible with the LLVM dialect.
     static bool isCompatibleType(Type);
 
+    /// Name of the attribute mapped to LLVM's 'readnone' function attribute.
+    /// It is allowed on any FunctionOpInterface operations.
+    static StringRef getReadnoneAttrName() {
+      return "llvm.readnone";
+    }
+
   private:
     /// A cache storing compatible LLVM types that have been verified. This
     /// can save us lots of verification time if there are many occurrences
Index: mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
===================================================================
--- mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
+++ mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
@@ -2861,6 +2861,17 @@
              << "' to be a `loopopts` attribute";
   }
 
+  if (attr.getName() == LLVMDialect::getReadnoneAttrName()) {
+    const auto attrName = LLVMDialect::getReadnoneAttrName();
+    if (!isa<FunctionOpInterface>(op))
+      return op->emitOpError()
+             << "'" << attrName
+             << "' is permitted only on FunctionOpInterface operations";
+    if (!attr.getValue().isa<UnitAttr>())
+      return op->emitOpError()
+             << "expected '" << attrName << "' to be a unit attribute";
+  }
+
   if (attr.getName() == LLVMDialect::getStructAttrsAttrName()) {
     return op->emitOpError()
            << "'" << LLVM::LLVMDialect::getStructAttrsAttrName()
Index: mlir/lib/Target/LLVMIR/ConvertFromLLVMIR.cpp
===================================================================
--- mlir/lib/Target/LLVMIR/ConvertFromLLVMIR.cpp
+++ mlir/lib/Target/LLVMIR/ConvertFromLLVMIR.cpp
@@ -168,6 +168,10 @@
   /// Imports `f` into the current module.
   LogicalResult processFunction(llvm::Function *f);
 
+  /// Converts function attributes of LLVM Function \p f
+  /// into LLVM dialect attributes of LLVMFuncOp \p funcOp.
+  void processFunctionAttributes(llvm::Function *f, LLVMFuncOp funcOp);
+
   /// Imports GV as a GlobalOp, creating it if it doesn't exist.
   GlobalOp processGlobal(llvm::GlobalVariable *gv);
 
@@ -1165,6 +1169,15 @@
   return FlatSymbolRefAttr();
 }
 
+void Importer::processFunctionAttributes(llvm::Function *func,
+                                         LLVMFuncOp funcOp) {
+  auto addNamedUnitAttr = [&](StringRef name) {
+    return funcOp->setAttr(name, UnitAttr::get(context));
+  };
+  if (func->hasFnAttribute(llvm::Attribute::ReadNone))
+    addNamedUnitAttr(LLVMDialect::getReadnoneAttrName());
+}
+
 LogicalResult Importer::processFunction(llvm::Function *f) {
   blocks.clear();
   instMap.clear();
@@ -1199,6 +1212,9 @@
   if (f->hasGC())
     fop.setGarbageCollectorAttr(b.getStringAttr(f->getGC()));
 
+  // Handle Function attributes.
+  processFunctionAttributes(f, fop);
+
   if (f->isDeclaration())
     return success();
 
Index: mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
===================================================================
--- mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
+++ mlir/lib/Target/LLVMIR/ModuleTranslation.cpp
@@ -927,6 +927,10 @@
     mapFunction(function.getName(), llvmFunc);
     addRuntimePreemptionSpecifier(function.getDsoLocal(), llvmFunc);
 
+    if (function->getAttrOfType<UnitAttr>(LLVMDialect::getReadnoneAttrName())) {
+      llvmFunc->addFnAttr(llvm::Attribute::ReadNone);
+    }
+
     // Forward the pass-through attributes to LLVM.
     if (failed(forwardPassthroughAttributes(
             function.getLoc(), function.getPassthrough(), llvmFunc)))
Index: mlir/test/Dialect/LLVMIR/func.mlir
===================================================================
--- mlir/test/Dialect/LLVMIR/func.mlir
+++ mlir/test/Dialect/LLVMIR/func.mlir
@@ -277,3 +277,21 @@
   "llvm.func"() ({
   }) {sym_name = "generic_unknown_calling_convention", CConv = #llvm.cconv<cc_12>, function_type = !llvm.func<i64 (i64, i64)>} : () -> ()
 }
+
+// -----
+
+module {
+  // expected-error@+3 {{'llvm.readnone' is permitted only on FunctionOpInterface operations}}
+  "llvm.func"() ({
+  ^bb0:
+    llvm.return {llvm.readnone}
+  }) {sym_name = "readnone_return", function_type = !llvm.func<void ()>} : () -> ()
+}
+
+// -----
+
+module {
+  // expected-error@+1 {{op expected 'llvm.readnone' to be a unit attribute}}
+  "llvm.func"() ({
+  }) {sym_name = "readnone_func", llvm.readnone = true, function_type = !llvm.func<void ()>} : () -> ()
+}
Index: mlir/test/Target/LLVMIR/Import/function_attributes.ll
===================================================================
--- /dev/null
+++ mlir/test/Target/LLVMIR/Import/function_attributes.ll
@@ -0,0 +1,17 @@
+; RUN: mlir-translate -import-llvm -split-input-file %s | FileCheck %s
+
+// -----
+
+; CHECK: llvm.func @readnone_attr() attributes {llvm.readnone}
+declare void @readnone_attr() #0
+attributes #0 = { readnone }
+
+// -----
+
+; CHECK: llvm.func @readnone_attr() attributes {llvm.readnone} {
+; CHECK:   llvm.return
+; CHECK: }
+define void @readnone_attr() readnone {
+entry:
+  ret void
+}
Index: mlir/test/Target/LLVMIR/llvmir.mlir
===================================================================
--- mlir/test/Target/LLVMIR/llvmir.mlir
+++ mlir/test/Target/LLVMIR/llvmir.mlir
@@ -1937,3 +1937,11 @@
   // CHECK: ret void
   llvm.return
 }
+
+// -----
+
+// Function attributes: readnone
+
+// CHECK: declare void @readnone_function() #[[ATTR:[0-9]+]]
+// CHECK: attributes #[[ATTR]] = { readnone }
+llvm.func @readnone_function() attributes {llvm.readnone}