--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/llvm/lib/Support/RISCVAttributeParser.cpp	Mon May 25 11:55:54 2020 +0900
@@ -0,0 +1,67 @@
+//===-- RISCVAttributeParser.cpp - RISCV Attribute Parser -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/RISCVAttributeParser.h"
+#include "llvm/ADT/StringExtras.h"
+
+using namespace llvm;
+
+const RISCVAttributeParser::DisplayHandler
+    RISCVAttributeParser::displayRoutines[] = {
+        {
+            RISCVAttrs::ARCH,
+            &ELFAttributeParser::stringAttribute,
+        },
+        {
+            RISCVAttrs::PRIV_SPEC,
+            &ELFAttributeParser::integerAttribute,
+        },
+        {
+            RISCVAttrs::PRIV_SPEC_MINOR,
+            &ELFAttributeParser::integerAttribute,
+        },
+        {
+            RISCVAttrs::PRIV_SPEC_REVISION,
+            &ELFAttributeParser::integerAttribute,
+        },
+        {
+            RISCVAttrs::STACK_ALIGN,
+            &RISCVAttributeParser::stackAlign,
+        },
+        {
+            RISCVAttrs::UNALIGNED_ACCESS,
+            &RISCVAttributeParser::unalignedAccess,
+        }};
+
+Error RISCVAttributeParser::unalignedAccess(unsigned tag) {
+  static const char *strings[] = {"No unaligned access", "Unaligned access"};
+  return parseStringAttribute("Unaligned_access", tag, makeArrayRef(strings));
+}
+
+Error RISCVAttributeParser::stackAlign(unsigned tag) {
+  uint64_t value = de.getULEB128(cursor);
+  std::string description =
+      "Stack alignment is " + utostr(value) + std::string("-bytes");
+  printAttribute(tag, value, description);
+  return Error::success();
+}
+
+Error RISCVAttributeParser::handler(uint64_t tag, bool &handled) {
+  handled = false;
+  for (unsigned AHI = 0, AHE = array_lengthof(displayRoutines); AHI != AHE;
+       ++AHI) {
+    if (uint64_t(displayRoutines[AHI].attribute) == tag) {
+      if (Error e = (this->*displayRoutines[AHI].routine)(tag))
+        return e;
+      handled = true;
+      break;
+    }
+  }
+
+  return Error::success();
+}