llvm-objdump: add coff import library symbol listing support

This adds behaviour similar to binutils' objdump which can show symbols in an
import library.  Differences from that stem around the fact that we do not
create section symbols nor the all import import descriptor symbol reference.
However, this does mean that the tool can serve as a possible replacement for
the existing tool.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279088 91177308-0d34-0410-b5e6-96231b3b80d8

test/tools/llvm-objdump/coff-import-library.test

@@ -0,0 +1,12 @@
+RUN: llvm-objdump -t %p/Inputs/library.lib
+
+CHECK: [ 0](sec  0)(fl 0x00)(ty   0)(scl   0) (nx 0) 0x00000000 __imp__constant
+
+CHECK: [ 0](sec  0)(fl 0x00)(ty   0)(scl   0) (nx 0) 0x00000000 __imp__data
+
+CHECK: [ 0](sec  0)(fl 0x00)(ty   0)(scl   0) (nx 0) 0x00000000 __imp__function
+CHECK: [ 1](sec  0)(fl 0x00)(ty  20)(scl   0) (nx 0) 0x00000000 _function
+
+CHECK: [ 0](sec  0)(fl 0x00)(ty   0)(scl   0) (nx 0) 0x00000000 __imp__ordinal
+CHECK: [ 1](sec  0)(fl 0x00)(ty  20)(scl   0) (nx 0) 0x00000000 _ordinal
+

tools/llvm-objdump/COFFDump.cpp

@@ -17,6 +17,7 @@
 
 #include "llvm-objdump.h"
 #include "llvm/Object/COFF.h"
+#include "llvm/Object/COFFImportFile.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/SourceMgr.h"
@@ -617,6 +618,29 @@ void llvm::printCOFFFileHeader(const object::ObjectFile *Obj) {
   printExportTable(file);
 }
 
+void llvm::printCOFFSymbolTable(const object::COFFImportFile *i) {
+  unsigned Index = 0;
+  bool IsCode = i->getCOFFImportHeader()->getType() == COFF::IMPORT_CODE;
+
+  for (const object::BasicSymbolRef &Sym : i->symbols()) {
+    std::string Name;
+    raw_string_ostream NS(Name);
+
+    Sym.printName(NS);
+    NS.flush();
+
+    outs() << "[" << format("%2d", Index) << "]"
+           << "(sec " << format("%2d", 0) << ")"
+           << "(fl 0x00)" // Flag bits, which COFF doesn't have.
+           << "(ty " << format("%3x", (IsCode && Index) ? 32 : 0) << ")"
+           << "(scl " << format("%3x", 0) << ") "
+           << "(nx " << 0 << ") "
+           << "0x" << format("%08x", 0) << " " << Name << '\n';
+
+    ++Index;
+  }
+}
+
 void llvm::printCOFFSymbolTable(const COFFObjectFile *coff) {
   for (unsigned SI = 0, SE = coff->getNumberOfSymbols(); SI != SE; ++SI) {
     ErrorOr<COFFSymbolRef> Symbol = coff->getSymbol(SI);

tools/llvm-objdump/llvm-objdump.cpp

@@ -37,6 +37,7 @@
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/COFF.h"
+#include "llvm/Object/COFFImportFile.h"
 #include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Object/MachO.h"
 #include "llvm/Object/ObjectFile.h"
@@ -1824,6 +1825,20 @@ static void DumpObject(const ObjectFile *o, const Archive *a = nullptr) {
   }
 }
 
+static void DumpObject(const COFFImportFile *I, const Archive *A) {
+  StringRef ArchiveName = A ? A->getFileName() : "";
+
+  // Avoid other output when using a raw option.
+  if (!RawClangAST)
+    outs() << '\n'
+           << ArchiveName << "(" << I->getFileName() << ")"
+           << ":\tfile format COFF-import-file"
+           << "\n\n";
+
+  if (SymbolTable)
+    printCOFFSymbolTable(I);
+}
+
 /// @brief Dump each object file in \a a;
 static void DumpArchive(const Archive *a) {
   Error Err;
@@ -1836,6 +1851,8 @@ static void DumpArchive(const Archive *a) {
     }
     if (ObjectFile *o = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
       DumpObject(o, a);
+    else if (COFFImportFile *I = dyn_cast<COFFImportFile>(&*ChildOrErr.get()))
+      DumpObject(I, a);
     else
       report_error(a->getFileName(), object_error::invalid_file_type);
   }

tools/llvm-objdump/llvm-objdump.h

@@ -20,6 +20,7 @@ class StringRef;
 
 namespace object {
   class COFFObjectFile;
+  class COFFImportFile;
   class MachOObjectFile;
   class ObjectFile;
   class Archive;
@@ -74,6 +75,7 @@ void printMachOLazyBindTable(const object::MachOObjectFile* o);
 void printMachOWeakBindTable(const object::MachOObjectFile* o);
 void printELFFileHeader(const object::ObjectFile *o);
 void printCOFFFileHeader(const object::ObjectFile *o);
+void printCOFFSymbolTable(const object::COFFImportFile *i);
 void printCOFFSymbolTable(const object::COFFObjectFile *o);
 void printMachOFileHeader(const object::ObjectFile *o);
 void printMachOLoadCommands(const object::ObjectFile *o);