[ARM] Create objdump subtarget from build attributes

[samparker]

Summary

My previous commits were reverted in D28683, this patch reapplies them along with the fix from D28678 which has already been accepted. The only original addition that this patch introduces is a check in setARMSubArch to ensure that the CPU_arch attribute exists before trying to read it, as it would seem to be causing the sanitizer failure.

[rengolin]

Hi Sam,

Now that we have a bit more time, would you mind running it through an LLD check?

--renato

[samparker]

Hi Renato,

Yes, I've added LLD to my local build so I know that passes now. But I'm not sure about the issue raised by the sanitizer buildbot, I've fixed the obvious bug on the line reported by the sanitizer and I hope that is all that needs doing.

Cheers,
sam

[rengolin]

Ok, let's try it again.

include/llvm/Object/ELFObjectFile.h

 #include "llvm/Object/Error.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Object/SymbolicFile.h"
+#include "llvm/Support/ARMAttributeParser.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ELF.h"
 #include "llvm/Support/Endian.h"

   static inline bool classof(const Binary *v) { return v->isELF(); }
 
   SubtargetFeatures getFeatures() const override;
+
+  void setARMSubArch(Triple &TheTriple) const override;
 };
 
 class ELFSectionRef : public SectionRef {

     return std::error_code();
   }
 
+  std::error_code getBuildAttributes(ARMAttributeParser &Attributes) const override {
+    auto SectionsOrErr = EF.sections();
+    if (!SectionsOrErr)
+      return errorToErrorCode(SectionsOrErr.takeError());
+
+    for (const Elf_Shdr &Sec : *SectionsOrErr) {
+      if (Sec.sh_type == ELF::SHT_ARM_ATTRIBUTES) {
+        auto ErrorOrContents = EF.getSectionContents(&Sec);
+        if (!ErrorOrContents)
+          return errorToErrorCode(ErrorOrContents.takeError());
+
+        auto Contents = ErrorOrContents.get();
+        if (Contents[0] != ARMBuildAttrs::Format_Version || Contents.size() == 1)
+          return std::error_code();
+
+        Attributes.Parse(Contents, ELFT::TargetEndianness == support::little);
+        break;
+      }
+    }
+    return std::error_code();
+  }
+
   const ELFFile<ELFT> *getELFFile() const { return &EF; }
 
   bool isDyldType() const { return isDyldELFObject; }

include/llvm/Object/ObjectFile.h

 #include <cstring>
 
 namespace llvm {
+class ARMAttributeParser;
+
 namespace object {
 
 class ObjectFile;

   virtual StringRef getFileFormatName() const = 0;
   virtual /* Triple::ArchType */ unsigned getArch() const = 0;
   virtual SubtargetFeatures getFeatures() const = 0;
+  virtual void setARMSubArch(Triple &TheTriple) const { }
 
   /// Returns platform-specific object flags, if any.
   virtual std::error_code getPlatformFlags(unsigned &Result) const {

     return object_error::invalid_file_type;
   }
 
+  virtual std::error_code
+    getBuildAttributes(ARMAttributeParser &Attributes) const {
+      return std::error_code();
+    }
+
   /// True if this is a relocatable object (.o/.obj).
   virtual bool isRelocatableObject() const = 0;
 

include/llvm/Support/ARMAttributeParser.h

 #include "ARMBuildAttributes.h"
 #include "ScopedPrinter.h"
 
+#include <map>
+
 namespace llvm {
 class StringRef;
 
 class ARMAttributeParser {
-  ScopedPrinter &SW;
+  ScopedPrinter *SW;
 
+  std::map<unsigned, unsigned> Attributes;
+
   struct DisplayHandler {
     ARMBuildAttrs::AttrType Attribute;
     void (ARMAttributeParser::*Routine)(ARMBuildAttrs::AttrType,

                       SmallVectorImpl<uint8_t> &IndexList);
   void ParseSubsection(const uint8_t *Data, uint32_t Length);
 public:
-  ARMAttributeParser(ScopedPrinter &SW) : SW(SW) {}
+  ARMAttributeParser(ScopedPrinter *SW) : SW(SW) {}
 
-  void Parse(ArrayRef<uint8_t> Section);
+  ARMAttributeParser() : SW(nullptr) { }
+
+  void Parse(ArrayRef<uint8_t> Section, bool isLittle);
+
+  bool hasAttribute(unsigned Tag) const {
+    return Attributes.count(Tag);
+  }
+
+  unsigned getAttributeValue(unsigned Tag) const {
+    return Attributes.find(Tag)->second;
+  }
 };
 
 }

include/llvm/Support/ARMBuildAttributes.h

   WCharWidth2Bytes = 2, // sizeof(wchar_t) == 2
   WCharWidth4Bytes = 4, // sizeof(wchar_t) == 4
 
+  // Tag_ABI_align_needed, (=24), uleb128
+  Align8Byte = 1,
+  Align4Byte = 2,
+  AlignReserved = 3,
+
+  // Tag_ABI_align_needed, (=25), uleb128
+  AlignNotPreserved = 0,
+  AlignPreserve8Byte = 1,
+  AlignPreserveAll = 2,
+
   // Tag_ABI_FP_denormal, (=20), uleb128
   PositiveZero = 0,
   IEEEDenormals = 1,

   PreserveFPSign = 2, // sign when flushed-to-zero is preserved
 
   // Tag_ABI_FP_number_model, (=23), uleb128
+  AllowIEEENormal = 1,
   AllowRTABI = 2,  // numbers, infinities, and one quiet NaN (see [RTABI])
-  AllowIEE754 = 3, // this code to use all the IEEE 754-defined FP encodings
+  AllowIEEE754 = 3, // this code to use all the IEEE 754-defined FP encodings
 
   // Tag_ABI_enum_size, (=26), uleb128
   EnumProhibited = 0, // The user prohibited the use of enums when building

 
   // Tag_FP_16bit_format, (=38), uleb128
   FP16FormatIEEE = 1,
+  FP16VFP3 = 2,
 
   // Tag_MPextension_use, (=42), uleb128
   AllowMP = 1, // Allow use of MP extensions

lib/Object/ELFObjectFile.cpp

   }
 }
 
+// FIXME Encode from a tablegen description or target parser.
+void ELFObjectFileBase::setARMSubArch(Triple &TheTriple) const {
+  if (TheTriple.getSubArch() != Triple::NoSubArch)
+    return;
+
+  ARMAttributeParser Attributes;
+  std::error_code EC = getBuildAttributes(Attributes);
+  if (EC)
+    return;
+
+  std::string Triple;
+  // Default to ARM, but use the triple if it's been set.
+  if (TheTriple.getArch() == Triple::thumb ||
+      TheTriple.getArch() == Triple::thumbeb)
+    Triple = "thumb";
+  else
+    Triple = "arm";
+
+  if (Attributes.hasAttribute(ARMBuildAttrs::CPU_arch)) {
+    switch(Attributes.getAttributeValue(ARMBuildAttrs::CPU_arch)) {
+    case ARMBuildAttrs::v4:
+      Triple += "v4";
+      break;
+    case ARMBuildAttrs::v4T:
+      Triple += "v4t";
+      break;
+    case ARMBuildAttrs::v5T:
+      Triple += "v5t";
+      break;
+    case ARMBuildAttrs::v5TE:
+      Triple += "v5te";
+      break;
+    case ARMBuildAttrs::v5TEJ:
+      Triple += "v5tej";
+      break;
+    case ARMBuildAttrs::v6:
+      Triple += "v6";
+      break;
+    case ARMBuildAttrs::v6KZ:
+      Triple += "v6kz";
+      break;
+    case ARMBuildAttrs::v6T2:
+      Triple += "v6t2";
+      break;
+    case ARMBuildAttrs::v6K:
+      Triple += "v6k";
+      break;
+    case ARMBuildAttrs::v7:
+      Triple += "v7";
+      break;
+    case ARMBuildAttrs::v6_M:
+      Triple += "v6m";
+      break;
+    case ARMBuildAttrs::v6S_M:
+      Triple += "v6sm";
+      break;
+    case ARMBuildAttrs::v7E_M:
+      Triple += "v7em";
+      break;
+    }
+  }
+  if (!isLittleEndian())
+    Triple += "eb";
+
+  TheTriple.setArchName(Triple);
+}
+
 } // end namespace llvm

lib/Support/ARMAttributeParser.cpp

 
 void ARMAttributeParser::IntegerAttribute(AttrType Tag, const uint8_t *Data,
                                           uint32_t &Offset) {
-  SW.printNumber(ARMBuildAttrs::AttrTypeAsString(Tag),
-                 ParseInteger(Data, Offset));
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  Attributes.insert(std::make_pair(Tag, Value));
+
+  if (SW)
+    SW->printNumber(ARMBuildAttrs::AttrTypeAsString(Tag), Value);
 }
 
 void ARMAttributeParser::StringAttribute(AttrType Tag, const uint8_t *Data,
                                          uint32_t &Offset) {
   StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag, /*TagPrefix*/false);
+  StringRef ValueDesc = ParseString(Data, Offset);
 
-  DictScope AS(SW, "Attribute");
-  SW.printNumber("Tag", Tag);
-  if (!TagName.empty())
-    SW.printString("TagName", TagName);
-  SW.printString("Value", ParseString(Data, Offset));
+  if (SW) {
+    DictScope AS(*SW, "Attribute");
+    SW->printNumber("Tag", Tag);
+    if (!TagName.empty())
+      SW->printString("TagName", TagName);
+    SW->printString("Value", ValueDesc);
+  }
 }
 
 void ARMAttributeParser::PrintAttribute(unsigned Tag, unsigned Value,
                                         StringRef ValueDesc) {
-  StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag, /*TagPrefix*/false);
+  Attributes.insert(std::make_pair(Tag, Value));
 
-  DictScope AS(SW, "Attribute");
-  SW.printNumber("Tag", Tag);
-  SW.printNumber("Value", Value);
-  if (!TagName.empty())
-    SW.printString("TagName", TagName);
-  if (!ValueDesc.empty())
-    SW.printString("Description", ValueDesc);
+  if (SW) {
+    StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag,
+                                                        /*TagPrefix*/false);
+    DictScope AS(*SW, "Attribute");
+    SW->printNumber("Tag", Tag);
+    SW->printNumber("Value", Value);
+    if (!TagName.empty())
+      SW->printString("TagName", TagName);
+    if (!ValueDesc.empty())
+      SW->printString("Description", ValueDesc);
+  }
 }
 
 void ARMAttributeParser::CPU_arch(AttrType Tag, const uint8_t *Data,

   uint64_t Integer = ParseInteger(Data, Offset);
   StringRef String = ParseString(Data, Offset);
 
-  DictScope AS(SW, "Attribute");
-  SW.printNumber("Tag", Tag);
-  SW.startLine() << "Value: " << Integer << ", " << String << '\n';
-  SW.printString("TagName", AttrTypeAsString(Tag, /*TagPrefix*/false));
-  switch (Integer) {
-  case 0:
-    SW.printString("Description", StringRef("No Specific Requirements"));
-    break;
-  case 1:
-    SW.printString("Description", StringRef("AEABI Conformant"));
-    break;
-  default:
-    SW.printString("Description", StringRef("AEABI Non-Conformant"));
-    break;
+  if (SW) {
+    DictScope AS(*SW, "Attribute");
+    SW->printNumber("Tag", Tag);
+    SW->startLine() << "Value: " << Integer << ", " << String << '\n';
+    SW->printString("TagName", AttrTypeAsString(Tag, /*TagPrefix*/false));
+    switch (Integer) {
+    case 0:
+      SW->printString("Description", StringRef("No Specific Requirements"));
+      break;
+    case 1:
+      SW->printString("Description", StringRef("AEABI Conformant"));
+      break;
+    default:
+      SW->printString("Description", StringRef("AEABI Non-Conformant"));
+      break;
+    }
   }
 }
 

 void ARMAttributeParser::ParseSubsection(const uint8_t *Data, uint32_t Length) {
   uint32_t Offset = sizeof(uint32_t); /* SectionLength */
 
-  SW.printNumber("SectionLength", Length);
-
   const char *VendorName = reinterpret_cast<const char*>(Data + Offset);
   size_t VendorNameLength = std::strlen(VendorName);
-  SW.printString("Vendor", StringRef(VendorName, VendorNameLength));
   Offset = Offset + VendorNameLength + 1;
 
-  if (StringRef(VendorName, VendorNameLength).lower() != "aeabi")
+  if (SW) {
+    SW->printNumber("SectionLength", Length);
+    SW->printString("Vendor", StringRef(VendorName, VendorNameLength));
+  }
+
+  if (StringRef(VendorName, VendorNameLength).lower() != "aeabi") {
     return;
+  }
 
   while (Offset < Length) {
     /// Tag_File | Tag_Section | Tag_Symbol   uleb128:byte-size
     uint8_t Tag = Data[Offset];
-    SW.printEnum("Tag", Tag, makeArrayRef(TagNames));
     Offset = Offset + sizeof(Tag);
 
     uint32_t Size =
       *reinterpret_cast<const support::ulittle32_t*>(Data + Offset);
-    SW.printNumber("Size", Size);
     Offset = Offset + sizeof(Size);
 
+    if (SW) {
+      SW->printEnum("Tag", Tag, makeArrayRef(TagNames));
+      SW->printNumber("Size", Size);
+    }
+
     if (Size > Length) {
       errs() << "subsection length greater than section length\n";
       return;

       return;
     }
 
-    DictScope ASS(SW, ScopeName);
-
+    if (SW) {
+      DictScope ASS(*SW, ScopeName);
       if (!Indicies.empty())
-      SW.printList(IndexName, Indicies);
-
-    ParseAttributeList(Data, Offset, Length);
+        SW->printList(IndexName, Indicies);
+      ParseAttributeList(Data, Offset, Length);
+    } else {
+      ParseAttributeList(Data, Offset, Length);
+    }
   }
 }
 
-void ARMAttributeParser::Parse(ArrayRef<uint8_t> Section) {
+void ARMAttributeParser::Parse(ArrayRef<uint8_t> Section, bool isLittle) {
   size_t Offset = 1;
   unsigned SectionNumber = 0;
 
   while (Offset < Section.size()) {
-    uint32_t SectionLength =
-      *reinterpret_cast<const support::ulittle32_t*>(Section.data() + Offset);
+    uint32_t SectionLength = isLittle ?
+      support::endian::read32le(Section.data() + Offset) :
+      support::endian::read32be(Section.data() + Offset);
 
-    SW.startLine() << "Section " << ++SectionNumber << " {\n";
-    SW.indent();
+    if (SW) {
+      SW->startLine() << "Section " << ++SectionNumber << " {\n";
+      SW->indent();
+    }
 
     ParseSubsection(Section.data() + Offset, SectionLength);
     Offset = Offset + SectionLength;
 
-    SW.unindent();
-    SW.startLine() << "}\n";
+    if (SW) {
+      SW->unindent();
+      SW->startLine() << "}\n";
+    }
   }
 }
 }

lib/Target/ARM/ARMAsmPrinter.cpp

                       ARMBuildAttrs::Allowed);
   else
     ATS.emitAttribute(ARMBuildAttrs::ABI_FP_number_model,
-                      ARMBuildAttrs::AllowIEE754);
+                      ARMBuildAttrs::AllowIEEE754);
 
   if (STI.allowsUnalignedMem())
     ATS.emitAttribute(ARMBuildAttrs::CPU_unaligned_access,

test/tools/llvm-objdump/ARM/v5t-subarch.s

+@ RUN: llvm-mc < %s -triple armv5t-elf -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.arch armv5t
+
+clz:
+clz r0, r1
+
+@ CHECK-LABEL: clz
+@ CHECK: 11 0f 6f e1
+

test/tools/llvm-objdump/ARM/v5te-subarch.s

+@ RUN: llvm-mc < %s -triple armv5te-elf -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.arch armv5te
+
+strd:
+strd r0, r1, [r2, +r3]
+
+@ CHECK-LABEL strd
+@ CHECK: f3 00 82 e1 strd r0, r1, [r2, r3]
+

test/tools/llvm-objdump/ARM/v5tej-subarch.s

+@ RUN: llvm-mc < %s -triple armv5tej-elf -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+bxj:
+bxj r0
+
+@ CHECK-LABEL: bxj
+@ CHECK: 20 ff 2f e1 bxj r0

test/tools/llvm-objdump/ARM/v6-subarch.s

+@ RUN: llvm-mc < %s -triple armv6-elf -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.arch armv6
+
+umaal:
+umaal r0, r1, r2, r3
+
+@ CHECK-LABEL:umaal
+@ CHECK: 92 03 41 e0 umaal r0, r1, r2, r3

test/tools/llvm-objdump/ARM/v6k-subarch.s

+@ RUN: llvm-mc < %s -triple armv6k-elf -filetype=obj | llvm-objdump -triple=arm -d - | FileCheck %s
+
+.arch armv6k
+
+clrex:
+clrex
+
+@ CHECK-LABEL: clrex
+@ CHECK: 1f f0 7f f5 clrex

test/tools/llvm-objdump/ARM/v6m-subarch.s

+@ RUN: llvm-mc < %s -triple armv6m-elf -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+
+.arch armv6m
+
+dmb:
+dmb
+
+@ CHECK-LABEL: dmb
+@ CHECK: bf f3 5f 8f dmb sy

test/tools/llvm-objdump/ARM/v6t2-subarch.s

+@ RUN: llvm-mc < %s -triple armv6t2-elf -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+
+.arch armv6t2
+
+.thumb
+umaalt2:
+umaal r0, r1, r2, r3
+
+@ CHECK-LABEL: umaalt2
+@ CHECK: e2 fb 63 01 umaal r0, r1, r2, r3

test/tools/llvm-objdump/ARM/v7m-subarch.s

+@ RUN: llvm-mc < %s -triple armv7m-elf -filetype=obj | llvm-objdump -triple=thumb -d - | FileCheck %s
+
+.arch armv7m
+
+umlal:
+umlal r0, r1, r2, r3
+
+@ CHECK-LABEL: umlal
+@ CHECK: e2 fb 03 01 umlal r0, r1, r2, r3
+

tools/llvm-objdump/llvm-objdump.cpp

   llvm::Triple TheTriple("unknown-unknown-unknown");
   if (TripleName.empty()) {
     if (Obj) {
-      TheTriple.setArch(Triple::ArchType(Obj->getArch()));
+      auto Arch = Obj->getArch();
+      TheTriple.setArch(Triple::ArchType(Arch));
+
+      // For ARM targets, try to use the build attributes to build determine
+      // the build target. Target features are also added, but later during
+      // disassembly.
+      if (Arch == Triple::arm || Arch == Triple::armeb) {
+        Obj->setARMSubArch(TheTriple);
+      }
+
       // TheTriple defaults to ELF, and COFF doesn't have an environment:
       // the best we can do here is indicate that it is mach-o.
       if (Obj->isMachO())

           TheTriple.setTriple("thumbv7-windows");
       }
     }
-  } else
+  } else {
     TheTriple.setTriple(Triple::normalize(TripleName));
+    // Use the triple, but also try to combine with ARM build attributes.
+    if (Obj) {
+      auto Arch = Obj->getArch();
+      if (Arch == Triple::arm || Arch == Triple::armeb) {
+        Obj->setARMSubArch(TheTriple);
+      }
+    }
+  }
 
   // Get the target specific parser.
   std::string Error;

tools/llvm-readobj/ELFDumper.cpp

     if (Contents.size() == 1)
       continue;
 
-    ARMAttributeParser(W).Parse(Contents);
+    ARMAttributeParser(&W).Parse(Contents, true);
   }
 }
 }

unittests/Support/ARMAttributeParser.cpp

+#include "llvm/Support/ARMBuildAttributes.h"
+#include "llvm/Support/ARMAttributeParser.h"
+#include "llvm/Support/LEB128.h"
+#include "gtest/gtest.h"
+#include <string>
+
+using namespace llvm;
+
+struct AttributeSection {
+  unsigned Tag;
+  unsigned Value;
+
+  AttributeSection(unsigned tag, unsigned value) : Tag(tag), Value(value) { }
+
+  void write(raw_ostream &OS) {
+    OS.flush();
+    // length = length + "aeabi\0" + TagFile + ByteSize + Tag + Value;
+    // length = 17 bytes
+
+    OS << 'A' << (uint8_t)17 << (uint8_t)0 << (uint8_t)0 << (uint8_t)0;
+    OS << "aeabi" << '\0';
+    OS << (uint8_t)1 << (uint8_t)7 << (uint8_t)0 << (uint8_t)0 << (uint8_t)0;
+    OS << (uint8_t)Tag << (uint8_t)Value;
+
+  }
+};
+
+bool testBuildAttr(unsigned Tag, unsigned Value,
+                      unsigned ExpectedTag, unsigned ExpectedValue) {
+  std::string buffer;
+  raw_string_ostream OS(buffer);
+  AttributeSection Section(Tag, Value);
+  Section.write(OS);
+  ArrayRef<uint8_t> Bytes((uint8_t*)OS.str().c_str(), OS.str().size());
+
+  ARMAttributeParser Parser;
+  Parser.Parse(Bytes, true);
+
+  return (Parser.hasAttribute(ExpectedTag) &&
+    Parser.getAttributeValue(ExpectedTag) == ExpectedValue);
+}
+
+bool testTagString(unsigned Tag, const char *name) {
+  return ARMBuildAttrs::AttrTypeAsString(Tag).str() == name;
+}
+
+TEST(CPUArchBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(6, "Tag_CPU_arch"));
+
+  EXPECT_TRUE(testBuildAttr(6, 0, ARMBuildAttrs::CPU_arch,
+                            ARMBuildAttrs::Pre_v4));
+  EXPECT_TRUE(testBuildAttr(6, 1, ARMBuildAttrs::CPU_arch,
+                            ARMBuildAttrs::v4));
+  EXPECT_TRUE(testBuildAttr(6, 2, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v4T));
+  EXPECT_TRUE(testBuildAttr(6, 3, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v5T));
+  EXPECT_TRUE(testBuildAttr(6, 4, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v5TE));
+  EXPECT_TRUE(testBuildAttr(6, 5, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v5TEJ));
+  EXPECT_TRUE(testBuildAttr(6, 6, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6));
+  EXPECT_TRUE(testBuildAttr(6, 7, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6KZ));
+  EXPECT_TRUE(testBuildAttr(6, 8, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6T2));
+  EXPECT_TRUE(testBuildAttr(6, 9, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6K));
+  EXPECT_TRUE(testBuildAttr(6, 10, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v7));
+  EXPECT_TRUE(testBuildAttr(6, 11, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6_M));
+  EXPECT_TRUE(testBuildAttr(6, 12, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v6S_M));
+  EXPECT_TRUE(testBuildAttr(6, 13, ARMBuildAttrs::CPU_arch,
+                               ARMBuildAttrs::v7E_M));
+}
+
+TEST(CPUArchProfileBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(7, "Tag_CPU_arch_profile"));
+  EXPECT_TRUE(testBuildAttr(7, 'A', ARMBuildAttrs::CPU_arch_profile,
+                               ARMBuildAttrs::ApplicationProfile));
+  EXPECT_TRUE(testBuildAttr(7, 'R', ARMBuildAttrs::CPU_arch_profile,
+                               ARMBuildAttrs::RealTimeProfile));
+  EXPECT_TRUE(testBuildAttr(7, 'M', ARMBuildAttrs::CPU_arch_profile,
+                               ARMBuildAttrs::MicroControllerProfile));
+  EXPECT_TRUE(testBuildAttr(7, 'S', ARMBuildAttrs::CPU_arch_profile,
+                               ARMBuildAttrs::SystemProfile));
+}
+
+TEST(ARMISABuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(8, "Tag_ARM_ISA_use"));
+  EXPECT_TRUE(testBuildAttr(8, 0, ARMBuildAttrs::ARM_ISA_use,
+                               ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(8, 1, ARMBuildAttrs::ARM_ISA_use,
+                               ARMBuildAttrs::Allowed));
+}
+
+TEST(ThumbISABuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(9, "Tag_THUMB_ISA_use"));
+  EXPECT_TRUE(testBuildAttr(9, 0, ARMBuildAttrs::THUMB_ISA_use,
+                               ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(9, 1, ARMBuildAttrs::THUMB_ISA_use,
+                               ARMBuildAttrs::Allowed));
+}
+
+TEST(FPArchBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(10, "Tag_FP_arch"));
+  EXPECT_TRUE(testBuildAttr(10, 0, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(10, 1, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::Allowed));
+  EXPECT_TRUE(testBuildAttr(10, 2, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPv2));
+  EXPECT_TRUE(testBuildAttr(10, 3, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPv3A));
+  EXPECT_TRUE(testBuildAttr(10, 4, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPv3B));
+  EXPECT_TRUE(testBuildAttr(10, 5, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPv4A));
+  EXPECT_TRUE(testBuildAttr(10, 6, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPv4B));
+  EXPECT_TRUE(testBuildAttr(10, 7, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPARMv8A));
+  EXPECT_TRUE(testBuildAttr(10, 8, ARMBuildAttrs::FP_arch,
+                               ARMBuildAttrs::AllowFPARMv8B));
+}
+
+TEST(WMMXBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(11, "Tag_WMMX_arch"));
+  EXPECT_TRUE(testBuildAttr(11, 0, ARMBuildAttrs::WMMX_arch,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(11, 1, ARMBuildAttrs::WMMX_arch,
+                            ARMBuildAttrs::AllowWMMXv1));
+  EXPECT_TRUE(testBuildAttr(11, 2, ARMBuildAttrs::WMMX_arch,
+                            ARMBuildAttrs::AllowWMMXv2));
+}
+
+TEST(SIMDBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(12, "Tag_Advanced_SIMD_arch"));
+  EXPECT_TRUE(testBuildAttr(12, 0, ARMBuildAttrs::Advanced_SIMD_arch,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(12, 1, ARMBuildAttrs::Advanced_SIMD_arch,
+                            ARMBuildAttrs::AllowNeon));
+  EXPECT_TRUE(testBuildAttr(12, 2, ARMBuildAttrs::Advanced_SIMD_arch,
+                            ARMBuildAttrs::AllowNeon2));
+  EXPECT_TRUE(testBuildAttr(12, 3, ARMBuildAttrs::Advanced_SIMD_arch,
+                            ARMBuildAttrs::AllowNeonARMv8));
+  EXPECT_TRUE(testBuildAttr(12, 4, ARMBuildAttrs::Advanced_SIMD_arch,
+                            ARMBuildAttrs::AllowNeonARMv8_1a));
+}
+
+TEST(FPHPBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(36, "Tag_FP_HP_extension"));
+  EXPECT_TRUE(testBuildAttr(36, 0, ARMBuildAttrs::FP_HP_extension,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(36, 1, ARMBuildAttrs::FP_HP_extension,
+                            ARMBuildAttrs::AllowHPFP));
+}
+
+TEST(CPUAlignBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(34, "Tag_CPU_unaligned_access"));
+  EXPECT_TRUE(testBuildAttr(34, 0, ARMBuildAttrs::CPU_unaligned_access,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(34, 1, ARMBuildAttrs::CPU_unaligned_access,
+                            ARMBuildAttrs::Allowed));
+}
+
+TEST(T2EEBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(66, "Tag_T2EE_use"));
+  EXPECT_TRUE(testBuildAttr(66, 0, ARMBuildAttrs::T2EE_use,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(66, 1, ARMBuildAttrs::T2EE_use,
+                            ARMBuildAttrs::Allowed));
+}
+
+TEST(VirtualizationBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(68, "Tag_Virtualization_use"));
+  EXPECT_TRUE(testBuildAttr(68, 0, ARMBuildAttrs::Virtualization_use,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(68, 1, ARMBuildAttrs::Virtualization_use,
+                            ARMBuildAttrs::AllowTZ));
+  EXPECT_TRUE(testBuildAttr(68, 2, ARMBuildAttrs::Virtualization_use,
+                            ARMBuildAttrs::AllowVirtualization));
+  EXPECT_TRUE(testBuildAttr(68, 3, ARMBuildAttrs::Virtualization_use,
+                            ARMBuildAttrs::AllowTZVirtualization));
+}
+
+TEST(MPBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(42, "Tag_MPextension_use"));
+  EXPECT_TRUE(testBuildAttr(42, 0, ARMBuildAttrs::MPextension_use,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(42, 1, ARMBuildAttrs::MPextension_use,
+                            ARMBuildAttrs::AllowMP));
+}
+
+TEST(DivBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(44, "Tag_DIV_use"));
+  EXPECT_TRUE(testBuildAttr(44, 0, ARMBuildAttrs::DIV_use,
+                            ARMBuildAttrs::AllowDIVIfExists));
+  EXPECT_TRUE(testBuildAttr(44, 1, ARMBuildAttrs::DIV_use,
+                            ARMBuildAttrs::DisallowDIV));
+  EXPECT_TRUE(testBuildAttr(44, 2, ARMBuildAttrs::DIV_use,
+                            ARMBuildAttrs::AllowDIVExt));
+}
+
+TEST(PCS_ConfigBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(13, "Tag_PCS_config"));
+  EXPECT_TRUE(testBuildAttr(13, 0, ARMBuildAttrs::PCS_config, 0));
+  EXPECT_TRUE(testBuildAttr(13, 1, ARMBuildAttrs::PCS_config, 1));
+  EXPECT_TRUE(testBuildAttr(13, 2, ARMBuildAttrs::PCS_config, 2));
+  EXPECT_TRUE(testBuildAttr(13, 3, ARMBuildAttrs::PCS_config, 3));
+  EXPECT_TRUE(testBuildAttr(13, 4, ARMBuildAttrs::PCS_config, 4));
+  EXPECT_TRUE(testBuildAttr(13, 5, ARMBuildAttrs::PCS_config, 5));
+  EXPECT_TRUE(testBuildAttr(13, 6, ARMBuildAttrs::PCS_config, 6));
+  EXPECT_TRUE(testBuildAttr(13, 7, ARMBuildAttrs::PCS_config, 7));
+}
+
+TEST(PCS_R9BuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(14, "Tag_ABI_PCS_R9_use"));
+  EXPECT_TRUE(testBuildAttr(14, 0, ARMBuildAttrs::ABI_PCS_R9_use,
+                            ARMBuildAttrs::R9IsGPR));
+  EXPECT_TRUE(testBuildAttr(14, 1, ARMBuildAttrs::ABI_PCS_R9_use,
+                            ARMBuildAttrs::R9IsSB));
+  EXPECT_TRUE(testBuildAttr(14, 2, ARMBuildAttrs::ABI_PCS_R9_use,
+                            ARMBuildAttrs::R9IsTLSPointer));
+  EXPECT_TRUE(testBuildAttr(14, 3, ARMBuildAttrs::ABI_PCS_R9_use,
+                            ARMBuildAttrs::R9Reserved));
+}
+
+TEST(PCS_RWBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(15, "Tag_ABI_PCS_RW_data"));
+  EXPECT_TRUE(testBuildAttr(15, 0, ARMBuildAttrs::ABI_PCS_RW_data,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(15, 1, ARMBuildAttrs::ABI_PCS_RW_data,
+                            ARMBuildAttrs::AddressRWPCRel));
+  EXPECT_TRUE(testBuildAttr(15, 2, ARMBuildAttrs::ABI_PCS_RW_data,
+                            ARMBuildAttrs::AddressRWSBRel));
+  EXPECT_TRUE(testBuildAttr(15, 3, ARMBuildAttrs::ABI_PCS_RW_data,
+                            ARMBuildAttrs::AddressRWNone));
+}
+
+TEST(PCS_ROBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(16, "Tag_ABI_PCS_RO_data"));
+  EXPECT_TRUE(testBuildAttr(16, 0, ARMBuildAttrs::ABI_PCS_RO_data,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(16, 1, ARMBuildAttrs::ABI_PCS_RO_data,
+                            ARMBuildAttrs::AddressROPCRel));
+  EXPECT_TRUE(testBuildAttr(16, 2, ARMBuildAttrs::ABI_PCS_RO_data,
+                            ARMBuildAttrs::AddressRONone));
+}
+
+TEST(PCS_GOTBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(17, "Tag_ABI_PCS_GOT_use"));
+  EXPECT_TRUE(testBuildAttr(17, 0, ARMBuildAttrs::ABI_PCS_GOT_use,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(17, 1, ARMBuildAttrs::ABI_PCS_GOT_use,
+                            ARMBuildAttrs::AddressDirect));
+  EXPECT_TRUE(testBuildAttr(17, 2, ARMBuildAttrs::ABI_PCS_GOT_use,
+                            ARMBuildAttrs::AddressGOT));
+}
+
+TEST(PCS_WCharBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(18, "Tag_ABI_PCS_wchar_t"));
+  EXPECT_TRUE(testBuildAttr(18, 0, ARMBuildAttrs::ABI_PCS_wchar_t,
+                            ARMBuildAttrs::WCharProhibited));
+  EXPECT_TRUE(testBuildAttr(18, 2, ARMBuildAttrs::ABI_PCS_wchar_t,
+                            ARMBuildAttrs::WCharWidth2Bytes));
+  EXPECT_TRUE(testBuildAttr(18, 4, ARMBuildAttrs::ABI_PCS_wchar_t,
+                            ARMBuildAttrs::WCharWidth4Bytes));
+}
+
+TEST(EnumSizeBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(26, "Tag_ABI_enum_size"));
+  EXPECT_TRUE(testBuildAttr(26, 0, ARMBuildAttrs::ABI_enum_size,
+                            ARMBuildAttrs::EnumProhibited));
+  EXPECT_TRUE(testBuildAttr(26, 1, ARMBuildAttrs::ABI_enum_size,
+                            ARMBuildAttrs::EnumSmallest));
+  EXPECT_TRUE(testBuildAttr(26, 2, ARMBuildAttrs::ABI_enum_size,
+                            ARMBuildAttrs::Enum32Bit));
+  EXPECT_TRUE(testBuildAttr(26, 3, ARMBuildAttrs::ABI_enum_size,
+                            ARMBuildAttrs::Enum32BitABI));
+}
+
+TEST(AlignNeededBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(24, "Tag_ABI_align_needed"));
+  EXPECT_TRUE(testBuildAttr(24, 0, ARMBuildAttrs::ABI_align_needed,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(24, 1, ARMBuildAttrs::ABI_align_needed,
+                            ARMBuildAttrs::Align8Byte));
+  EXPECT_TRUE(testBuildAttr(24, 2, ARMBuildAttrs::ABI_align_needed,
+                            ARMBuildAttrs::Align4Byte));
+  EXPECT_TRUE(testBuildAttr(24, 3, ARMBuildAttrs::ABI_align_needed,
+                            ARMBuildAttrs::AlignReserved));
+}
+
+TEST(AlignPreservedBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(25, "Tag_ABI_align_preserved"));
+  EXPECT_TRUE(testBuildAttr(25, 0, ARMBuildAttrs::ABI_align_preserved,
+                            ARMBuildAttrs::AlignNotPreserved));
+  EXPECT_TRUE(testBuildAttr(25, 1, ARMBuildAttrs::ABI_align_preserved,
+                            ARMBuildAttrs::AlignPreserve8Byte));
+  EXPECT_TRUE(testBuildAttr(25, 2, ARMBuildAttrs::ABI_align_preserved,
+                            ARMBuildAttrs::AlignPreserveAll));
+  EXPECT_TRUE(testBuildAttr(25, 3, ARMBuildAttrs::ABI_align_preserved,
+                            ARMBuildAttrs::AlignReserved));
+}
+
+TEST(FPRoundingBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(19, "Tag_ABI_FP_rounding"));
+  EXPECT_TRUE(testBuildAttr(19, 0, ARMBuildAttrs::ABI_FP_rounding, 0));
+  EXPECT_TRUE(testBuildAttr(19, 1, ARMBuildAttrs::ABI_FP_rounding, 1));
+}
+
+TEST(FPDenormalBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(20, "Tag_ABI_FP_denormal"));
+  EXPECT_TRUE(testBuildAttr(20, 0, ARMBuildAttrs::ABI_FP_denormal,
+                            ARMBuildAttrs::PositiveZero));
+  EXPECT_TRUE(testBuildAttr(20, 1, ARMBuildAttrs::ABI_FP_denormal,
+                            ARMBuildAttrs::IEEEDenormals));
+  EXPECT_TRUE(testBuildAttr(20, 2, ARMBuildAttrs::ABI_FP_denormal,
+                            ARMBuildAttrs::PreserveFPSign));
+}
+
+TEST(FPExceptionsBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(21, "Tag_ABI_FP_exceptions"));
+  EXPECT_TRUE(testBuildAttr(21, 0, ARMBuildAttrs::ABI_FP_exceptions, 0));
+  EXPECT_TRUE(testBuildAttr(21, 1, ARMBuildAttrs::ABI_FP_exceptions, 1));
+}
+
+TEST(FPUserExceptionsBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(22, "Tag_ABI_FP_user_exceptions"));
+  EXPECT_TRUE(testBuildAttr(22, 0, ARMBuildAttrs::ABI_FP_user_exceptions, 0));
+  EXPECT_TRUE(testBuildAttr(22, 1, ARMBuildAttrs::ABI_FP_user_exceptions, 1));
+}
+
+TEST(FPNumberModelBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(23, "Tag_ABI_FP_number_model"));
+  EXPECT_TRUE(testBuildAttr(23, 0, ARMBuildAttrs::ABI_FP_number_model,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(23, 1, ARMBuildAttrs::ABI_FP_number_model,
+                            ARMBuildAttrs::AllowIEEENormal));
+  EXPECT_TRUE(testBuildAttr(23, 2, ARMBuildAttrs::ABI_FP_number_model,
+                            ARMBuildAttrs::AllowRTABI));
+  EXPECT_TRUE(testBuildAttr(23, 3, ARMBuildAttrs::ABI_FP_number_model,
+                            ARMBuildAttrs::AllowIEEE754));
+}
+
+TEST(FP16BuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(38, "Tag_ABI_FP_16bit_format"));
+  EXPECT_TRUE(testBuildAttr(38, 0, ARMBuildAttrs::ABI_FP_16bit_format,
+                            ARMBuildAttrs::Not_Allowed));
+  EXPECT_TRUE(testBuildAttr(38, 1, ARMBuildAttrs::ABI_FP_16bit_format,
+                            ARMBuildAttrs::FP16FormatIEEE));
+  EXPECT_TRUE(testBuildAttr(38, 2, ARMBuildAttrs::ABI_FP_16bit_format,
+                            ARMBuildAttrs::FP16VFP3));
+}
+
+TEST(HardFPBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(27, "Tag_ABI_HardFP_use"));
+  EXPECT_TRUE(testBuildAttr(27, 0, ARMBuildAttrs::ABI_HardFP_use,
+                            ARMBuildAttrs::HardFPImplied));
+  EXPECT_TRUE(testBuildAttr(27, 1, ARMBuildAttrs::ABI_HardFP_use,
+                            ARMBuildAttrs::HardFPSinglePrecision));
+  EXPECT_TRUE(testBuildAttr(27, 2, ARMBuildAttrs::ABI_HardFP_use, 2));
+}
+
+TEST(VFPArgsBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(28, "Tag_ABI_VFP_args"));
+  EXPECT_TRUE(testBuildAttr(28, 0, ARMBuildAttrs::ABI_VFP_args,
+                            ARMBuildAttrs::BaseAAPCS));
+  EXPECT_TRUE(testBuildAttr(28, 1, ARMBuildAttrs::ABI_VFP_args,
+                            ARMBuildAttrs::HardFPAAPCS));
+  EXPECT_TRUE(testBuildAttr(28, 2, ARMBuildAttrs::ABI_VFP_args, 2));
+  EXPECT_TRUE(testBuildAttr(28, 3, ARMBuildAttrs::ABI_VFP_args, 3));
+}
+
+TEST(WMMXArgsBuildAttr, testBuildAttr) {
+  EXPECT_TRUE(testTagString(29, "Tag_ABI_WMMX_args"));
+  EXPECT_TRUE(testBuildAttr(29, 0, ARMBuildAttrs::ABI_WMMX_args, 0));
+  EXPECT_TRUE(testBuildAttr(29, 1, ARMBuildAttrs::ABI_WMMX_args, 1));
+  EXPECT_TRUE(testBuildAttr(29, 2, ARMBuildAttrs::ABI_WMMX_args, 2));
+}

unittests/Support/CMakeLists.txt

 add_llvm_unittest(SupportTests
   AlignOfTest.cpp
   AllocatorTest.cpp
+  ARMAttributeParser.cpp
   ArrayRecyclerTest.cpp
   BlockFrequencyTest.cpp
   BranchProbabilityTest.cpp