Add --offoading option to llvm-readobj (#143342)

Utilize new extensions to LLVM Offloading API to
handle offloading fatbin Bundles.

The tool will output a list of available offload bundles
using URI syntax.

---------

Co-authored-by: dsalinas_amdeng <david.salinas@amd.com>

Author: david-salinas

llvm/docs/CommandGuide/llvm-readelf.rst

@@ -143,6 +143,10 @@ OPTIONS
 
  Display all notes.
 
+.. option:: --offloading
+
+ Display list of HIP offload bundles.
+
 .. option:: --pretty-print
 
  When used with :option:`--elf-output-style`, JSON output will be formatted in

llvm/docs/CommandGuide/llvm-readobj.rst

@@ -104,6 +104,10 @@ file formats.
  Do not demangle symbol names in the output. This option is only for ELF and
  XCOFF file formats. The option is enabled by default.
 
+.. option:: --offloading
+
+ Display list of HIP offload bundles.
+
 .. option:: --relocations, --relocs, -r
 
  Display the relocation entries in the file.

llvm/include/llvm/Object/OffloadBundle.h

@@ -161,7 +161,7 @@ struct OffloadBundleURI {
     OffsetStr.getAsInteger(10, O);
     Str = Str.drop_front(OffsetStr.size());
 
-    if (Str.consume_front("&size="))
+    if (!Str.consume_front("&size="))
       return createStringError(object_error::parse_failed,
                                "Reading 'size' in URI");
 

llvm/lib/Object/OffloadBundle.cpp

@@ -89,17 +89,17 @@ Error OffloadBundleFatBin::readEntries(StringRef Buffer,
     uint64_t EntryIDSize;
     StringRef EntryID;
 
-    if (auto EC = Reader.readInteger(EntryOffset))
-      return errorCodeToError(object_error::parse_failed);
+    if (Error Err = Reader.readInteger(EntryOffset))
+      return Err;
 
-    if (auto EC = Reader.readInteger(EntrySize))
-      return errorCodeToError(object_error::parse_failed);
+    if (Error Err = Reader.readInteger(EntrySize))
+      return Err;
 
-    if (auto EC = Reader.readInteger(EntryIDSize))
-      return errorCodeToError(object_error::parse_failed);
+    if (Error Err = Reader.readInteger(EntryIDSize))
+      return Err;
 
-    if (auto EC = Reader.readFixedString(EntryID, EntryIDSize))
-      return errorCodeToError(object_error::parse_failed);
+    if (Error Err = Reader.readFixedString(EntryID, EntryIDSize))
+      return Err;
 
     auto Entry = std::make_unique<OffloadBundleEntry>(
         EntryOffset + SectionOffset, EntrySize, EntryIDSize, EntryID);
@@ -125,7 +125,7 @@ OffloadBundleFatBin::create(MemoryBufferRef Buf, uint64_t SectionOffset,
   // Read the Bundle Entries
   Error Err = TheBundle->readEntries(Buf.getBuffer(), SectionOffset);
   if (Err)
-    return errorCodeToError(object_error::parse_failed);
+    return Err;
 
   return std::unique_ptr<OffloadBundleFatBin>(TheBundle);
 }

llvm/test/tools/llvm-readobj/ELF/AMDGPU/offloading-fail.test

@@ -16,6 +16,8 @@
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/Decompressor.h"
 #include "llvm/Object/ObjectFile.h"
+#include "llvm/Object/OffloadBinary.h"
+#include "llvm/Object/OffloadBundle.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/ScopedPrinter.h"
@@ -230,4 +232,14 @@ void ObjDumper::printSectionsAsHex(const object::ObjectFile &Obj,
   }
 }
 
+void ObjDumper::printOffloading(const object::ObjectFile &Obj) {
+  SmallVector<llvm::object::OffloadBundleFatBin> Bundles;
+  if (Error Err = object::extractOffloadBundleFatBinary(Obj, Bundles))
+    reportWarning(std::move(Err), Obj.getFileName());
+
+  // Print out all the FatBin Bundles that are contained in this buffer.
+  for (const auto &[Index, Bundle] : llvm::enumerate(Bundles))
+    Bundle.printEntriesAsURI();
+}
+
 } // namespace llvm

llvm/test/tools/llvm-readobj/ELF/AMDGPU/offloading.test

@@ -16,6 +16,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Object/ObjectFile.h"
+#include "llvm/Object/OffloadBinary.h"
 #include "llvm/Support/CommandLine.h"
 
 #include <unordered_set>
@@ -188,6 +189,7 @@ class ObjDumper {
   std::function<Error(const Twine &Msg)> WarningHandler;
   void reportUniqueWarning(Error Err) const;
   void reportUniqueWarning(const Twine &Msg) const;
+  void printOffloading(const object::ObjectFile &Obj);
 
 protected:
   ScopedPrinter &W;

llvm/tools/llvm-readobj/ObjDumper.cpp

@@ -32,6 +32,7 @@ def file_header : FF<"file-header", "Display file header">;
 def headers : FF<"headers", "Equivalent to setting: --file-header, --program-headers, --section-headers">;
 defm hex_dump : Eq<"hex-dump", "Display the specified section(s) as hexadecimal bytes">, MetaVarName<"<name or index>">;
 def pretty_print : FF<"pretty-print", "Pretty print JSON output">;
+def offloading : FF<"offloading", "Display the content of the offloading section">;
 def relocs : FF<"relocs", "Display the relocation entries in the file">;
 def section_data : FF<"section-data", "Display section data for each section shown. This option has no effect for GNU style output">;
 def section_details : FF<"section-details", "Display the section details">;

llvm/tools/llvm-readobj/ObjDumper.h

@@ -135,6 +135,7 @@ static bool HashHistogram;
 static bool Memtag;
 static bool NeededLibraries;
 static bool Notes;
+static bool Offloading;
 static bool ProgramHeaders;
 static bool SectionGroups;
 static std::vector<std::string> SFrame;
@@ -274,6 +275,7 @@ static void parseOptions(const opt::InputArgList &Args) {
   opts::Memtag = Args.hasArg(OPT_memtag);
   opts::NeededLibraries = Args.hasArg(OPT_needed_libs);
   opts::Notes = Args.hasArg(OPT_notes);
+  opts::Offloading = Args.hasArg(OPT_offloading);
   opts::PrettyPrint = Args.hasArg(OPT_pretty_print);
   opts::ProgramHeaders = Args.hasArg(OPT_program_headers);
   opts::SectionGroups = Args.hasArg(OPT_section_groups);
@@ -459,6 +461,8 @@ static void dumpObject(ObjectFile &Obj, ScopedPrinter &Writer,
     Dumper->printGnuHashTable();
   if (opts::VersionInfo)
     Dumper->printVersionInfo();
+  if (opts::Offloading)
+    Dumper->printOffloading(Obj);
   if (opts::StringTable)
     Dumper->printStringTable();
   if (Obj.isELF()) {
@@ -707,6 +711,7 @@ int llvm_readobj_main(int argc, char **argv, const llvm::ToolContext &) {
     opts::DynamicTable = true;
     opts::Notes = true;
     opts::VersionInfo = true;
+    opts::Offloading = true;
     opts::UnwindInfo = true;
     opts::SectionGroups = true;
     opts::HashHistogram = true;