[llvm-objdump] Add --file-headers (-f) option

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336284 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Object/COFF.h

@@ -928,6 +928,7 @@ public:
   uint8_t getBytesInAddress() const override;
   StringRef getFileFormatName() const override;
   Triple::ArchType getArch() const override;
+  Expected<uint64_t> getStartAddress() const override;
   SubtargetFeatures getFeatures() const override { return SubtargetFeatures(); }
 
   import_directory_iterator import_directory_begin() const;

include/llvm/Object/ELFObjectFile.h

@@ -373,6 +373,7 @@ public:
   uint8_t getBytesInAddress() const override;
   StringRef getFileFormatName() const override;
   Triple::ArchType getArch() const override;
+  Expected<uint64_t> getStartAddress() const override;
 
   unsigned getPlatformFlags() const override { return EF.getHeader()->e_flags; }
 
@@ -1143,6 +1144,11 @@ template <class ELFT> Triple::ArchType ELFObjectFile<ELFT>::getArch() const {
   }
 }
 
+template <class ELFT>
+Expected<uint64_t> ELFObjectFile<ELFT>::getStartAddress() const {
+  return EF.getHeader()->e_entry;
+}
+
 template <class ELFT>
 ELFObjectFileBase::elf_symbol_iterator_range
 ELFObjectFile<ELFT>::getDynamicSymbolIterators() const {

include/llvm/Object/ObjectFile.h

@@ -287,6 +287,9 @@ public:
   virtual Triple::ArchType getArch() const = 0;
   virtual SubtargetFeatures getFeatures() const = 0;
   virtual void setARMSubArch(Triple &TheTriple) const { }
+  virtual Expected<uint64_t> getStartAddress() const {
+    return errorCodeToError(object_error::parse_failed);
+  };
 
   /// Create a triple from the data in this object file.
   Triple makeTriple() const;

lib/Object/COFFObjectFile.cpp

@@ -910,6 +910,12 @@ Triple::ArchType COFFObjectFile::getArch() const {
   }
 }
 
+Expected<uint64_t> COFFObjectFile::getStartAddress() const {
+  if (PE32Header)
+    return PE32Header->AddressOfEntryPoint;
+  return 0;
+}
+
 iterator_range<import_directory_iterator>
 COFFObjectFile::import_directories() const {
   return make_range(import_directory_begin(), import_directory_end());

test/tools/llvm-objdump/file-headers-coff.test

@@ -0,0 +1,13 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objdump -f %t | FileCheck %s
+# RUN: llvm-objdump -file-headers %t | FileCheck %s
+
+!COFF
+header: !Header
+  Machine: IMAGE_FILE_MACHINE_I386 # (0x14c)
+  Characteristics: [ IMAGE_FILE_DEBUG_STRIPPED ]
+sections:
+symbols:
+
+# CHECK: architecture: i386
+# CHECK: start address: 0x0000

test/tools/llvm-objdump/file-headers-elf.test

@@ -0,0 +1,14 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objdump -f %t | FileCheck %s
+# RUN: llvm-objdump -file-headers %t | FileCheck %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_X86_64
+  Entry:           0x123456
+
+# CHECK: architecture: x86_64
+# CHECK: start address: 0x00123456

test/tools/llvm-objdump/file-headers-pe.test

@@ -0,0 +1,33 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objdump -f %t | FileCheck %s
+# RUN: llvm-objdump -file-headers %t | FileCheck %s
+
+!COFF
+header: !Header
+  Machine: IMAGE_FILE_MACHINE_I386
+  Characteristics: [ IMAGE_FILE_DEBUG_STRIPPED ]
+OptionalHeader:
+  AddressOfEntryPoint: 0x1234
+# Unfortunately, all these flags are mandatory to set AddressOfEntryPoint.
+# All the values are randomly picked. They can't interfere in what
+# we are testing here.
+  SizeOfHeapCommit: 1024
+  SizeOfHeapReserve: 1024
+  SizeOfStackCommit: 1024
+  SizeOfStackReserve: 1024
+  DLLCharacteristics: [ IMAGE_DLL_CHARACTERISTICS_DYNAMIC_BASE ]
+  Subsystem: IMAGE_SUBSYSTEM_NATIVE
+  MinorSubsystemVersion: 1
+  MajorSubsystemVersion: 1
+  MinorImageVersion: 1
+  MajorImageVersion: 1
+  MinorOperatingSystemVersion: 1
+  MajorOperatingSystemVersion: 1
+  FileAlignment: 8
+  SectionAlignment: 8
+  ImageBase: 0x12
+sections:
+symbols:
+
+# CHECK: architecture: i386
+# CHECK: start address: 0x1234

test/tools/llvm-objdump/file-headers-unsupported.test

@@ -0,0 +1,3 @@
+# RUN: not llvm-objdump -file-headers %p/Inputs/trivial.obj.wasm 2>&1 | FileCheck %s
+
+# CHECK: Invalid/Unsupported object file format

tools/llvm-objdump/llvm-objdump.cpp

@@ -200,6 +200,13 @@ static cl::alias
 PrivateHeadersShort("p", cl::desc("Alias for --private-headers"),
                     cl::aliasopt(PrivateHeaders));
 
+cl::opt<bool> llvm::FileHeaders(
+    "file-headers",
+    cl::desc("Display the contents of the overall file header"));
+
+static cl::alias FileHeadersShort("f", cl::desc("Alias for --file-headers"),
+                                  cl::aliasopt(FileHeaders));
+
 cl::opt<bool>
     llvm::PrintImmHex("print-imm-hex",
                       cl::desc("Use hex format for immediate values"));
@@ -2123,6 +2130,20 @@ static void printPrivateFileHeaders(const ObjectFile *o, bool onlyFirst) {
   report_error(o->getFileName(), "Invalid/Unsupported object file format");
 }
 
+static void printFileHeaders(const ObjectFile *o) {
+  if (!o->isELF() && !o->isCOFF())
+    report_error(o->getFileName(), "Invalid/Unsupported object file format");
+
+  Triple::ArchType AT = o->getArch();
+  outs() << "architecture: " << Triple::getArchTypeName(AT) << "\n";
+  Expected<uint64_t> StartAddrOrErr = o->getStartAddress();
+  if (!StartAddrOrErr)
+    report_error(o->getFileName(), StartAddrOrErr.takeError());
+  outs() << "start address: "
+         << format("0x%0*x", o->getBytesInAddress(), StartAddrOrErr.get())
+         << "\n";
+}
+
 static void DumpObject(ObjectFile *o, const Archive *a = nullptr) {
   StringRef ArchiveName = a != nullptr ? a->getFileName() : "";
   // Avoid other output when using a raw option.
@@ -2151,6 +2172,8 @@ static void DumpObject(ObjectFile *o, const Archive *a = nullptr) {
     PrintUnwindInfo(o);
   if (PrivateHeaders || FirstPrivateHeader)
     printPrivateFileHeaders(o, FirstPrivateHeader);
+  if (FileHeaders)
+    printFileHeaders(o);
   if (ExportsTrie)
     printExportsTrie(o);
   if (Rebase)
@@ -2267,6 +2290,7 @@ int main(int argc, char **argv) {
       && !SymbolTable
       && !UnwindInfo
       && !PrivateHeaders
+      && !FileHeaders
       && !FirstPrivateHeader
       && !ExportsTrie
       && !Rebase

tools/llvm-objdump/llvm-objdump.h

@@ -38,6 +38,7 @@ extern cl::opt<bool> DisassembleAll;
 extern cl::opt<bool> NoShowRawInsn;
 extern cl::opt<bool> NoLeadingAddr;
 extern cl::opt<bool> PrivateHeaders;
+extern cl::opt<bool> FileHeaders;
 extern cl::opt<bool> FirstPrivateHeader;
 extern cl::opt<bool> ExportsTrie;
 extern cl::opt<bool> Rebase;