[lld] [llvm] [readobj][Arm][AArch64] Refactor Build Attributes parsing under ELFAtributeParser and add support for AArch64 Build Attributes (PR #128727)

[Oliver Stannard via llvm-commits]

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@@ -0,0 +1,82 @@
+//===- ELF AttributeParser.h - ELF Attribute Parser -------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_ELFCOMPACTATTRPARSER_H
+#define LLVM_SUPPORT_ELFCOMPACTATTRPARSER_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/ELFAttributeParser.h"
+#include "llvm/Support/ELFAttributes.h"
+#include "llvm/Support/Error.h"
+
+#include <optional>
+#include <unordered_map>
+
+namespace llvm {
+class StringRef;
+class ScopedPrinter;
+
+class ELFCompactAttrParser : public ELFAttributeParser {
+  StringRef vendor;
+  std::unordered_map<unsigned, unsigned> attributes;
+  std::unordered_map<unsigned, StringRef> attributesStr;
+
+  virtual Error handler(uint64_t tag, bool &handled) = 0;
+
+protected:
+  ScopedPrinter *sw;
+  TagNameMap tagToStringMap;
+  DataExtractor de{ArrayRef<uint8_t>{}, true, 0};
+  DataExtractor::Cursor cursor{0};
+
+  void printAttribute(unsigned tag, unsigned value, StringRef valueDesc);
+
+  Error parseStringAttribute(const char *name, unsigned tag,
+                             ArrayRef<const char *> strings);
+  Error parseAttributeList(uint32_t length);
+  void parseIndexList(SmallVectorImpl<uint8_t> &indexList);
+  Error parseSubsection(uint32_t length);
+
+  void setAttributeString(unsigned tag, StringRef value) {
+    attributesStr.emplace(tag, value);
+  }
+
+public:
+  virtual ~ELFCompactAttrParser() { static_cast<void>(!cursor.takeError()); }
+  Error integerAttribute(unsigned tag);
+  Error stringAttribute(unsigned tag);
+
+  ELFCompactAttrParser(ScopedPrinter *sw, TagNameMap tagNameMap,
+                       StringRef vendor)
+      : vendor(vendor), sw(sw), tagToStringMap(tagNameMap) {}
+  ELFCompactAttrParser(TagNameMap tagNameMap, StringRef vendor)
+      : vendor(vendor), sw(nullptr), tagToStringMap(tagNameMap) {}
+
+  Error parse(ArrayRef<uint8_t> section, llvm::endianness endian) override;
+
+  std::optional<unsigned>
+  getAttributeValue(StringRef buildAttributeSubsectionName,
----------------
ostannard wrote:

These should assert that `buildAttributeSubsectionName` is empty, since this class doesn't support subsections.

https://github.com/llvm/llvm-project/pull/128727