diff --git a/llvm/include/llvm/Support/ARMBuildAttributes.h b/llvm/include/llvm/Support/ARMBuildAttributes.h
--- a/llvm/include/llvm/Support/ARMBuildAttributes.h
+++ b/llvm/include/llvm/Support/ARMBuildAttributes.h
@@ -263,6 +263,8 @@
   PACRETUsed = 1
 };
 
+std::string encodeAttrTagValuePair(StringRef OriginalString);
+
 } // namespace ARMBuildAttrs
 } // namespace llvm
 
diff --git a/llvm/lib/Support/ARMBuildAttrs.cpp b/llvm/lib/Support/ARMBuildAttrs.cpp
--- a/llvm/lib/Support/ARMBuildAttrs.cpp
+++ b/llvm/lib/Support/ARMBuildAttrs.cpp
@@ -7,6 +7,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/ARMBuildAttributes.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Support/LEB128.h"
+#include <iomanip>
+#include <sstream>
 
 using namespace llvm;
 
@@ -71,3 +76,39 @@
 const TagNameMap &llvm::ARMBuildAttrs::getARMAttributeTags() {
   return ARMAttributeTags;
 }
+
+static std::string getEncodedULEB128AsText(const uint8_t *Value,
+                                           unsigned Size) {
+  std::stringstream SS;
+  for (unsigned i = 0; i < Size; ++i) {
+    SS << "\\" << std::setfill('0') << std::setw(3) << std::oct
+       << int(Value[i]);
+  }
+  return SS.str();
+}
+
+std::string
+llvm::ARMBuildAttrs::encodeAttrTagValuePair(StringRef OriginalString) {
+  auto BytesBegin = reinterpret_cast<const uint8_t *>(OriginalString.data());
+  auto BytesEnd = BytesBegin + OriginalString.size();
+
+  unsigned N = 0;
+  const char *Error = nullptr;
+  unsigned Tag = decodeULEB128(BytesBegin, &N, BytesEnd, &Error);
+  if (Error)
+    report_fatal_error("Could not decode Tag value: " + Twine(Error));
+
+  std::string EncodedPair = getEncodedULEB128AsText(BytesBegin, N);
+  switch (Tag) {
+  case ARMBuildAttrs::CPU_raw_name:
+  case ARMBuildAttrs::CPU_name:
+  case ARMBuildAttrs::compatibility:
+  case ARMBuildAttrs::conformance:
+    EncodedPair += OriginalString.substr(N);
+    break;
+  default:
+    EncodedPair +=
+        getEncodedULEB128AsText(BytesBegin + N, OriginalString.size() - N);
+  }
+  return EncodedPair;
+}
diff --git a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
--- a/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/llvm/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -11439,12 +11439,20 @@
       return true;
   }
 
+  std::string EscapedValue;
   if (IsStringValue) {
     if (Parser.getTok().isNot(AsmToken::String))
       return Error(Parser.getTok().getLoc(), "bad string constant");
 
-    StringValue = Parser.getTok().getStringContents();
-    Parser.Lex();
+    if (Tag == ARMBuildAttrs::also_compatible_with) {
+      if (Parser.parseEscapedString(EscapedValue))
+        return Error(Parser.getTok().getLoc(), "bad escaped string constant");
+
+      StringValue = EscapedValue;
+    } else {
+      StringValue = Parser.getTok().getStringContents();
+      Parser.Lex();
+    }
   }
 
   if (Parser.parseEOL())
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -202,7 +202,12 @@
     OS << "\t.cpu\t" << String.lower();
     break;
   default:
-    OS << "\t.eabi_attribute\t" << Attribute << ", \"" << String << "\"";
+    OS << "\t.eabi_attribute\t" << Attribute << ", \"";
+    if (Attribute == ARMBuildAttrs::also_compatible_with)
+      OS << ARMBuildAttrs::encodeAttrTagValuePair(String);
+    else
+      OS << String;
+    OS << "\"";
     if (IsVerboseAsm) {
       StringRef Name = ELFAttrs::attrTypeAsString(
           Attribute, ARMBuildAttrs::getARMAttributeTags());
diff --git a/llvm/test/CodeGen/ARM/build-attributes-encoding.s b/llvm/test/CodeGen/ARM/build-attributes-encoding.s
--- a/llvm/test/CodeGen/ARM/build-attributes-encoding.s
+++ b/llvm/test/CodeGen/ARM/build-attributes-encoding.s
@@ -63,6 +63,9 @@
 // Tag_BTI_extension (=52)
 .eabi_attribute 52, 0
 
+// Tag_also_compatible_with (=65)
+.eabi_attribute 65, "\006\017"
+
 // Tag_BTI_use (=74)
 .eabi_attribute 74, 0
 
@@ -86,16 +89,16 @@
 // CHECK-NEXT:    ]
 // CHECK-NEXT:    Address: 0x0
 // CHECK-NEXT:    Offset: 0x34
-// CHECK-NEXT:    Size: 81
+// CHECK-NEXT:    Size: 85
 // CHECK-NEXT:    Link: 0
 // CHECK-NEXT:    Info: 0
 // CHECK-NEXT:    AddressAlignment: 1
 // CHECK-NEXT:    EntrySize: 0
 // CHECK-NEXT:    SectionData (
-// CHECK-NEXT:      0000: 41500000 00616561 62690001 46000000  |AP...aeabi..F...|
+// CHECK-NEXT:      0000: 41540000 00616561 62690001 4A000000  |AT...aeabi..J...|
 // CHECK-NEXT:      0010: 05636F72 7465782D 61380006 0A074108  |.cortex-a8....A.|
 // CHECK-NEXT:      0020: 0109020A 030C0214 01150117 01180119  |................|
 // CHECK-NEXT:      0030: 011B001C 0124012A 012C022E 01320034  |.....$.*.,...2.4|
-// CHECK-NEXT:      0040: 0044034A 004C006E A0018101 3100FA01  |.D.J.L.n....1...|
-// CHECK-NEXT:      0050: 01                                   |.|
+// CHECK-NEXT:      0040: 0041060F 0044034A 004C006E A0018101  |.A...D.J.L.n....|
+// CHECK-NEXT:      0050: 3100FA01 01                          |1....|
 // CHECK-NEXT:    )
diff --git a/llvm/test/MC/ARM/directive-eabi_attribute.s b/llvm/test/MC/ARM/directive-eabi_attribute.s
--- a/llvm/test/MC/ARM/directive-eabi_attribute.s
+++ b/llvm/test/MC/ARM/directive-eabi_attribute.s
@@ -233,11 +233,14 @@
 @ CHECK-OBJ-NEXT:   Value: 0
 @ CHECK-OBJ-NEXT:   TagName: nodefaults
 @ CHECK-OBJ-NEXT:   Description: Unspecified Tags UNDEFINED
-	.eabi_attribute Tag_also_compatible_with, "gnu"
-@ CHECK: .eabi_attribute 65, "gnu"
+	.eabi_attribute Tag_also_compatible_with, "\006\017"
+@ The value for Tag_also_compatible_with should be a pair of a tag (ULEB128) +
+@ a value (ULEB128 + null or NTBS). llvm-readobj doesn't now how to process
+@ this yet, so we use the encoded value explicitly here.
+@ CHECK: .eabi_attribute 65, "\006\017"
 @ CHECK-OBJ:        Tag: 65
 @ CHECK-OBJ-NEXT:   TagName: also_compatible_with
-@ CHECK-OBJ-NEXT:   Value: gnu
+@ CHECK-OBJ-NEXT:   Value:
 	.eabi_attribute Tag_T2EE_use, 0
 @ CHECK: .eabi_attribute 66, 0
 @ CHECK-OBJ:        Tag: 66