From 808dcadd650fd54174a0c033547a6668bf77e4f1 Mon Sep 17 00:00:00 2001
From: Martell Malone <martellmalone@gmail.com>
Date: Wed, 28 Oct 2015 19:32:16 +0000
Subject: [PATCH 1/5] add support for gnu arguments in lld coff

---
 COFF/Driver.cpp      | 31 ++++++++++++++++++++++++++++++-
 COFF/Driver.h        |  3 +++
 COFF/DriverUtils.cpp |  2 +-
 COFF/Options.td      | 20 ++++++++++++++++++++
 tools/lld/lld.cpp    | 21 +++++++++++++++++++++
 5 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/COFF/Driver.cpp b/COFF/Driver.cpp
index bb6a60e..0821591 100644
--- a/COFF/Driver.cpp
+++ b/COFF/Driver.cpp
@@ -125,6 +125,7 @@ void LinkerDriver::parseDirectives(StringRef S) {
     case OPT_fastfail:
     case OPT_guardsym:
     case OPT_throwingnew:
+    case OPT_aligncomm:
       break;
     default:
       fatal(Arg->getSpelling() + " is not allowed in .drectve");
@@ -153,6 +154,31 @@ StringRef LinkerDriver::doFindFile(StringRef Filename) {
   return Filename;
 }
 
+// Searches a given library from input search paths, which are filled
+// from -L command line switches. Returns a path to an existent library file.
+StringRef LinkerDriver::searchLibrary(StringRef Filename) {
+
+  std::vector<std::string> Names;
+  if (Filename[0] == ':') {
+    Names.push_back(Filename.drop_front());
+  } else {
+    //if (!Config->Static)
+    Names.push_back(("lib" + Filename + ".dll.a").str());
+    Names.push_back(("lib" + Filename + ".a").str());
+  }
+
+  for (const std::string &Name : Names) {
+    for (StringRef Dir : SearchPaths) {
+      SmallString<128> Path = Dir;
+      llvm::sys::path::append(Path, Name.c_str());
+      if (llvm::sys::fs::exists(Path.str()))
+        return Alloc.save(Path.str());
+    }
+  }
+  fatal("Unable to find library -l" + Filename);
+  return "";
+}
+
 // Resolves a file path. This never returns the same path
 // (in that case, it returns None).
 Optional<StringRef> LinkerDriver::findFile(StringRef Filename) {
@@ -452,6 +478,9 @@ void LinkerDriver::link(llvm::ArrayRef<const char *> ArgsArr) {
   // for /defaultlib option.
   std::vector<StringRef> Paths;
   std::vector<MemoryBufferRef> MBs;
+  for (auto *Arg : Args.filtered(OPT_l))
+    if (Optional<StringRef> Path = searchLibrary(Arg->getValue()))
+      Paths.push_back(*Path);
   for (auto *Arg : Args.filtered(OPT_INPUT))
     if (Optional<StringRef> Path = findFile(Arg->getValue()))
       Paths.push_back(*Path);
@@ -573,7 +602,7 @@ void LinkerDriver::link(llvm::ArrayRef<const char *> ArgsArr) {
   if (Config->ImageBase == uint64_t(-1))
     Config->ImageBase = getDefaultImageBase();
 
-  Symtab.addRelative(mangle("__ImageBase"), 0);
+  Symtab.addRelative(mangle("__image_base__"), 0);
   if (Config->Machine == I386) {
     Config->SEHTable = Symtab.addRelative("___safe_se_handler_table", 0);
     Config->SEHCount = Symtab.addAbsolute("___safe_se_handler_count", 0);
diff --git a/COFF/Driver.h b/COFF/Driver.h
index 23969ee..230ec35 100644
--- a/COFF/Driver.h
+++ b/COFF/Driver.h
@@ -84,6 +84,9 @@ private:
   StringRef doFindFile(StringRef Filename);
   StringRef doFindLib(StringRef Filename);
 
+  // Searches for a gnu library
+  StringRef searchLibrary(StringRef Path);
+
   // Parses LIB environment which contains a list of search paths.
   void addLibSearchPaths();
 
diff --git a/COFF/DriverUtils.cpp b/COFF/DriverUtils.cpp
index 5d7dc2b..e2f1f2d 100644
--- a/COFF/DriverUtils.cpp
+++ b/COFF/DriverUtils.cpp
@@ -591,7 +591,7 @@ static const llvm::opt::OptTable::Info infoTable[] = {
 
 class COFFOptTable : public llvm::opt::OptTable {
 public:
-  COFFOptTable() : OptTable(infoTable, true) {}
+  COFFOptTable() : OptTable(infoTable) {}
 };
 
 // Parses a given list of options.
diff --git a/COFF/Options.td b/COFF/Options.td
index e5c9c5b..322b162 100644
--- a/COFF/Options.td
+++ b/COFF/Options.td
@@ -93,6 +93,26 @@ def nosymtab : F<"nosymtab">;
 // Flags for debugging
 def lldmap : Joined<["/", "-"], "lldmap:">;
 
+
+def output : Separate<["-"], "o">, Alias<out>;
+def L : Joined<["-"], "L">, Alias<libpath>;
+def e : Separate<["-"], "e">, Alias<entry>;
+def subs : Separate<["--"], "subsystem">, Alias<subsystem>;
+
+def l : JoinedOrSeparate<["-"], "l">, MetaVarName<"<libName>">;
+
+// Used to silence some gnu warnings
+def aligncomm : P<"aligncomm", "Comm Alignment">;
+def Bdynamic: Flag<["-"], "Bdynamic">;
+
+// Used to override gnu pe targets
+def m : Separate<["-"], "m">, MetaVarName<"<emulation>">,
+     HelpText<"Select target emulation">;
+
+// Select an optional flavor
+def flavor: Separate<["-"], "flavor">,
+     HelpText<"Flavor for linking, options are gnu/darwin/link">;
+
 //==============================================================================
 // The flags below do nothing. They are defined only for link.exe compatibility.
 //==============================================================================
diff --git a/tools/lld/lld.cpp b/tools/lld/lld.cpp
index 8805e02..68c8735 100644
--- a/tools/lld/lld.cpp
+++ b/tools/lld/lld.cpp
@@ -51,6 +51,24 @@ static Flavor getFlavor(StringRef S) {
       .Default(Invalid);
 }
 
+static bool isPETarget(const std::vector<const char *> &V) {
+  for (auto It = V.begin(); It != V.end(); It++) {
+    if (*It == StringRef("-m")) {
+      It++;
+      if (It == V.end())
+        return false;
+      if (*It == StringRef("i386pe"))
+        return true;
+      if (*It == StringRef("i386pep"))
+        return true;
+      if (*It == StringRef("thumb2pe"))
+        return true;
+      return false;
+    }
+  }
+  return false;
+}
+
 static Flavor parseProgname(StringRef Progname) {
 #if __APPLE__
   // Use Darwin driver for "ld" on Darwin.
@@ -101,6 +119,9 @@ int main(int Argc, const char **Argv) {
   llvm_shutdown_obj Shutdown;
 
   std::vector<const char *> Args(Argv, Argv + Argc);
+  if (isPETarget(Args))
+    return !coff::link(Args);
+
   switch (parseFlavor(Args)) {
   case Gnu:
     return !elf::link(Args);
-- 
2.7.4