tools: add support for decoding ARM attributes

Enhance the ARM specific parsing support in llvm-readobj to support attributes.
This allows for simpler tests to validate encoding of the build attributes as
specified in the ARM ELF specification.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200450 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 639 insertions, 0 deletions

diff --git a/tools/llvm-readobj/ARMAttributeParser.cpp b/tools/llvm-readobj/ARMAttributeParser.cpp
new file mode 100644
index 0000000000..a9f6a2eba6
--- /dev/null
+++ b/tools/llvm-readobj/ARMAttributeParser.cpp
@@ -0,0 +1,639 @@
+//===--- ARMAttributeParser.cpp - ARM Attribute Information Printer -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARMAttributeParser.h"
+#include "StreamWriter.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/LEB128.h"
+
+using namespace llvm;
+using namespace llvm::ARMBuildAttrs;
+
+
+static const EnumEntry<unsigned> TagNames[] = {
+  { "Tag_File", ARMBuildAttrs::File },
+  { "Tag_Section", ARMBuildAttrs::Section },
+  { "Tag_Symbol", ARMBuildAttrs::Symbol },
+};
+
+template <typename type_, size_t size_>
+size_t countof(const type_ (&)[size_]) {
+  return size_;
+}
+
+namespace llvm {
+#define ATTRIBUTE_HANDLER(Attr_)                                                \
+  { ARMBuildAttrs::Attr_, &ARMAttributeParser::Attr_ }
+
+const ARMAttributeParser::DisplayHandler
+ARMAttributeParser::DisplayRoutines[] = {
+  { ARMBuildAttrs::CPU_raw_name, &ARMAttributeParser::StringAttribute, },
+  { ARMBuildAttrs::CPU_name, &ARMAttributeParser::StringAttribute },
+  ATTRIBUTE_HANDLER(CPU_arch),
+  ATTRIBUTE_HANDLER(CPU_arch_profile),
+  ATTRIBUTE_HANDLER(ARM_ISA_use),
+  ATTRIBUTE_HANDLER(THUMB_ISA_use),
+  ATTRIBUTE_HANDLER(FP_arch),
+  ATTRIBUTE_HANDLER(WMMX_arch),
+  ATTRIBUTE_HANDLER(Advanced_SIMD_arch),
+  ATTRIBUTE_HANDLER(PCS_config),
+  ATTRIBUTE_HANDLER(ABI_PCS_R9_use),
+  ATTRIBUTE_HANDLER(ABI_PCS_RW_data),
+  ATTRIBUTE_HANDLER(ABI_PCS_RO_data),
+  ATTRIBUTE_HANDLER(ABI_PCS_GOT_use),
+  ATTRIBUTE_HANDLER(ABI_PCS_wchar_t),
+  ATTRIBUTE_HANDLER(ABI_FP_rounding),
+  ATTRIBUTE_HANDLER(ABI_FP_denormal),
+  ATTRIBUTE_HANDLER(ABI_FP_exceptions),
+  ATTRIBUTE_HANDLER(ABI_FP_user_exceptions),
+  ATTRIBUTE_HANDLER(ABI_FP_number_model),
+  ATTRIBUTE_HANDLER(ABI_align_needed),
+  ATTRIBUTE_HANDLER(ABI_align_preserved),
+  ATTRIBUTE_HANDLER(ABI_enum_size),
+  ATTRIBUTE_HANDLER(ABI_HardFP_use),
+  ATTRIBUTE_HANDLER(ABI_VFP_args),
+  ATTRIBUTE_HANDLER(ABI_WMMX_args),
+  ATTRIBUTE_HANDLER(ABI_optimization_goals),
+  ATTRIBUTE_HANDLER(ABI_FP_optimization_goals),
+  ATTRIBUTE_HANDLER(compatibility),
+  ATTRIBUTE_HANDLER(CPU_unaligned_access),
+  ATTRIBUTE_HANDLER(FP_HP_extension),
+  ATTRIBUTE_HANDLER(ABI_FP_16bit_format),
+  ATTRIBUTE_HANDLER(MPextension_use),
+  ATTRIBUTE_HANDLER(DIV_use),
+  ATTRIBUTE_HANDLER(T2EE_use),
+  ATTRIBUTE_HANDLER(Virtualization_use),
+  ATTRIBUTE_HANDLER(nodefaults)
+};
+
+#undef ATTRIBUTE_HANDLER
+
+uint64_t ARMAttributeParser::ParseInteger(const uint8_t *Data,
+                                          uint32_t &Offset) {
+  unsigned Length;
+  uint64_t Value = decodeULEB128(Data + Offset, &Length);
+  Offset = Offset + Length;
+  return Value;
+}
+
+StringRef ARMAttributeParser::ParseString(const uint8_t *Data,
+                                          uint32_t &Offset) {
+  const char *String = reinterpret_cast<const char*>(Data + Offset);
+  size_t Length = std::strlen(String);
+  Offset = Offset + Length + 1;
+  return StringRef(String, Length);
+}
+
+void ARMAttributeParser::IntegerAttribute(AttrType Tag, const uint8_t *Data,
+                                          uint32_t &Offset) {
+  SW.printNumber(ARMBuildAttrs::AttrTypeAsString(Tag),
+                 ParseInteger(Data, Offset));
+}
+
+void ARMAttributeParser::StringAttribute(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  StringRef TagName = ARMBuildAttrs::AttrTypeAsString(Tag, /*TagPrefix*/false);
+
+  DictScope AS(SW, "Attribute");
+  SW.printNumber("Tag", Tag);
+  if (!TagName.empty())
+    SW.printString("TagName", TagName);
+  SW.printString("Value", ParseString(Data, Offset));
+}
+
+void ARMAttributeParser::PrintAttribute(unsigned Tag, unsigned Value,
+                                        StringRef ValueDesc) {
+  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,
+                                  uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Pre-v4", "ARM v4", "ARM v4T", "ARM v5T", "ARM v5TE", "ARM v5TEJ", "ARM v6",
+    "ARM v6KZ", "ARM v6T2", "ARM v6K", "ARM v7", "ARM v6-M", "ARM v6S-M",
+    "ARM v7E-M", "ARM v8"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::CPU_arch_profile(AttrType Tag, const uint8_t *Data,
+                                          uint32_t &Offset) {
+  uint64_t Encoded = ParseInteger(Data, Offset);
+
+  StringRef Profile;
+  switch (Encoded) {
+  default:  Profile = "Unknown"; break;
+  case 'A': Profile = "Application"; break;
+  case 'R': Profile = "Real-time"; break;
+  case 'M': Profile = "Microcontroller"; break;
+  case 'S': Profile = "Classic"; break;
+  case '0': Profile = "None"; break;
+  }
+
+  PrintAttribute(Tag, Encoded, Profile);
+}
+
+void ARMAttributeParser::ARM_ISA_use(AttrType Tag, const uint8_t *Data,
+                                     uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "Permitted" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::THUMB_ISA_use(AttrType Tag, const uint8_t *Data,
+                                       uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "Thumb-1", "Thumb-2" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::FP_arch(AttrType Tag, const uint8_t *Data,
+                                 uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "VFPv1", "VFPv2", "VFPv3", "VFPv3-D16", "VFPv4",
+    "VFPv4-D16", "ARMv8-a FP", "ARMv8-a FP-D16"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::WMMX_arch(AttrType Tag, const uint8_t *Data,
+                                   uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "WMMXv1", "WMMXv2" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::Advanced_SIMD_arch(AttrType Tag, const uint8_t *Data,
+                                            uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "NEONv1", "NEONv2+FMA", "ARMv8-a NEON"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::PCS_config(AttrType Tag, const uint8_t *Data,
+                                    uint32_t &Offset) {
+  static const char *Strings[] = {
+    "None", "Bare Platform", "Linux Application", "Linux DSO", "Palm OS 2004",
+    "Reserved (Palm OS)", "Symbian OS 2004", "Reserved (Symbian OS)"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_PCS_R9_use(AttrType Tag, const uint8_t *Data,
+                                        uint32_t &Offset) {
+  static const char *Strings[] = { "v6", "Static Base", "TLS", "Unused" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_PCS_RW_data(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Absolute", "PC-relative", "SB-relative", "Not Permitted"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_PCS_RO_data(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "Absolute", "PC-relative", "Not Permitted" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_PCS_GOT_use(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "Direct", "GOT-Indirect" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_PCS_wchar_t(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "Unknown", "2-byte", "Unknown", "4-byte"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_rounding(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "IEEE-754", "Runtime" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_denormal(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "Unsupported", "IEEE-754", "Sign Only" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_exceptions(AttrType Tag, const uint8_t *Data,
+                                           uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "IEEE-754" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_user_exceptions(AttrType Tag,
+                                                const uint8_t *Data,
+                                                uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "IEEE-754" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_number_model(AttrType Tag, const uint8_t *Data,
+                                             uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "Finite Only", "RTABI", "IEEE-754"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_align_needed(AttrType Tag, const uint8_t *Data,
+                                          uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "8-byte alignment", "4-byte alignment", "Reserved"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+
+  Twine Description;
+  if (Value < countof(Strings))
+    Description = StringRef(Strings[Value]);
+  else if (Value <= 12)
+    Description = Twine("8-byte alignment, ") + utostr(exp2(Value))
+                + Twine("-byte extended alignment");
+  else
+    Description = "Invalid";
+
+  PrintAttribute(Tag, Value, Description.str());
+}
+
+void ARMAttributeParser::ABI_align_preserved(AttrType Tag, const uint8_t *Data,
+                                             uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Required", "8-byte data alignment", "8-byte data and code alignment",
+    "Reserved"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+
+  Twine Description;
+  if (Value < countof(Strings))
+    Description = StringRef(Strings[Value]);
+  else if (Value <= 12)
+    Description = Twine("8-byte stack alignment, ") + utostr(exp2(Value))
+                + Twine("-byte data alignment");
+  else
+    Description = "Invalid";
+
+  PrintAttribute(Tag, Value, Description.str());
+}
+
+void ARMAttributeParser::ABI_enum_size(AttrType Tag, const uint8_t *Data,
+                                       uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "Packed", "Int32", "External Int32"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_HardFP_use(AttrType Tag, const uint8_t *Data,
+                                        uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Tag_FP_arch", "Single-Precision", "Reserved", "Tag_FP_arch (deprecated)"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_VFP_args(AttrType Tag, const uint8_t *Data,
+                                      uint32_t &Offset) {
+  static const char *Strings[] = {
+    "AAPCS", "AAPCS VFP", "Custom", "Not Permitted"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_WMMX_args(AttrType Tag, const uint8_t *Data,
+                                       uint32_t &Offset) {
+  static const char *Strings[] = { "AAPCS", "iWMMX", "Custom" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_optimization_goals(AttrType Tag,
+                                                const uint8_t *Data,
+                                                uint32_t &Offset) {
+  static const char *Strings[] = {
+    "None", "Speed", "Aggressive Speed", "Size", "Aggressive Size", "Debugging",
+    "Best Debugging"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_optimization_goals(AttrType Tag,
+                                                   const uint8_t *Data,
+                                                   uint32_t &Offset) {
+  static const char *Strings[] = {
+    "None", "Speed", "Aggressive Speed", "Size", "Aggressive Size", "Accuracy",
+    "Best Accuracy"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::compatibility(AttrType Tag, const uint8_t *Data,
+                                       uint32_t &Offset) {
+  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;
+  }
+}
+
+void ARMAttributeParser::CPU_unaligned_access(AttrType Tag, const uint8_t *Data,
+                                              uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "v6-style" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::FP_HP_extension(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "If Available", "Permitted" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::ABI_FP_16bit_format(AttrType Tag, const uint8_t *Data,
+                                             uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "IEEE-754", "VFPv3" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::MPextension_use(AttrType Tag, const uint8_t *Data,
+                                         uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "Permitted" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::DIV_use(AttrType Tag, const uint8_t *Data,
+                                 uint32_t &Offset) {
+  static const char *Strings[] = {
+    "If Available", "Not Permitted", "Permitted"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::T2EE_use(AttrType Tag, const uint8_t *Data,
+                                  uint32_t &Offset) {
+  static const char *Strings[] = { "Not Permitted", "Permitted" };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::Virtualization_use(AttrType Tag, const uint8_t *Data,
+                                            uint32_t &Offset) {
+  static const char *Strings[] = {
+    "Not Permitted", "TrustZone", "Virtualization Extensions",
+    "TrustZone + Virtualization Extensions"
+  };
+
+  uint64_t Value = ParseInteger(Data, Offset);
+  StringRef ValueDesc = (Value < countof(Strings)) ? Strings[Value] : NULL;
+  PrintAttribute(Tag, Value, ValueDesc);
+}
+
+void ARMAttributeParser::nodefaults(AttrType Tag, const uint8_t *Data,
+                                    uint32_t &Offset) {
+  uint64_t Value = ParseInteger(Data, Offset);
+  PrintAttribute(Tag, Value, "Unspecified Tags UNDEFINED");
+}
+
+void ARMAttributeParser::ParseIndexList(const uint8_t *Data, uint32_t &Offset,
+                                        SmallVectorImpl<uint8_t> &IndexList) {
+  for (;;) {
+    unsigned Length;
+    uint64_t Value = decodeULEB128(Data + Offset, &Length);
+    Offset = Offset + Length;
+    if (Value == 0)
+      break;
+    IndexList.push_back(Value);
+  }
+}
+
+void ARMAttributeParser::ParseAttributeList(const uint8_t *Data,
+                                            uint32_t &Offset, uint32_t Length) {
+  while (Offset < Length) {
+    unsigned Length;
+    uint64_t Tag = decodeULEB128(Data + Offset, &Length);
+    Offset += Length;
+
+    bool Handled = false;
+    for (unsigned AHI = 0, AHE = countof(DisplayRoutines);
+         AHI != AHE && !Handled; ++AHI) {
+      if (DisplayRoutines[AHI].Attribute == Tag) {
+        (this->*DisplayRoutines[AHI].Routine)(ARMBuildAttrs::AttrType(Tag),
+                                              Data, Offset);
+        Handled = true;
+        break;
+      }
+    }
+    if (!Handled) {
+      if (Tag < 32) {
+        errs() << "unhandled AEABI Tag " << Tag
+               << " (" << ARMBuildAttrs::AttrTypeAsString(Tag) << ")\n";
+        continue;
+      }
+
+      if (Tag % 2 == 0)
+        IntegerAttribute(ARMBuildAttrs::AttrType(Tag), Data, Offset);
+      else
+        StringAttribute(ARMBuildAttrs::AttrType(Tag), Data, Offset);
+    }
+  }
+}
+
+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")
+    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 (Size > Length) {
+      errs() << "subsection length greater than section length\n";
+      return;
+    }
+
+    StringRef ScopeName, IndexName;
+    SmallVector<uint8_t, 8> Indicies;
+    switch (Tag) {
+    case ARMBuildAttrs::File:
+      ScopeName = "FileAttributes";
+      break;
+    case ARMBuildAttrs::Section:
+      ScopeName = "SectionAttributes";
+      IndexName = "Sections";
+      ParseIndexList(Data, Offset, Indicies);
+      break;
+    case ARMBuildAttrs::Symbol:
+      ScopeName = "SymbolAttributes";
+      IndexName = "Symbols";
+      ParseIndexList(Data, Offset, Indicies);
+      break;
+    default:
+      errs() << "unrecognised tag: 0x" << utohexstr(Tag) << '\n';
+      return;
+    }
+
+    DictScope ASS(SW, ScopeName);
+
+    if (!Indicies.empty())
+      SW.printList(IndexName, Indicies);
+
+    ParseAttributeList(Data, Offset, Length);
+  }
+}
+
+void ARMAttributeParser::Parse(ArrayRef<uint8_t> Section) {
+  size_t Offset = 1;
+  unsigned SectionNumber = 0;
+
+  while (Offset < Section.size()) {
+    uint32_t SectionLength =
+      *reinterpret_cast<const support::ulittle32_t*>(Section.data() + Offset);
+
+    SW.startLine() << "Section " << ++SectionNumber << " {\n";
+    SW.indent();
+
+    ParseSubsection(Section.data() + Offset, SectionLength);
+    Offset = Offset + SectionLength;
+
+    SW.unindent();
+    SW.startLine() << "}\n";
+  }
+}
+}
+