1 files changed, 22 insertions, 2 deletions

diff --git a/tools/llvm-mc/llvm-mc.cpp b/tools/llvm-mc/llvm-mc.cpp
index 280a1bb..4281259 100644
--- a/tools/llvm-mc/llvm-mc.cpp
+++ b/tools/llvm-mc/llvm-mc.cpp
@@ -152,6 +152,10 @@ NoInitialTextSection("n", cl::desc("Don't assume assembly file starts "
 static cl::opt<bool>
 SaveTempLabels("L", cl::desc("Don't discard temporary labels"));
 
+static cl::opt<bool>
+GenDwarfForAssembly("g", cl::desc("Generate dwarf debugging info for assembly "
+                                  "source files"));
+
 enum ActionType {
   AC_AsLex,
   AC_Assemble,
@@ -175,7 +179,7 @@ Action(cl::desc("Action to perform:"),
 static const Target *GetTarget(const char *ProgName) {
   // Figure out the target triple.
   if (TripleName.empty())
-    TripleName = sys::getHostTriple();
+    TripleName = sys::getDefaultTargetTriple();
   Triple TheTriple(Triple::normalize(TripleName));
 
   const Target *TheTarget = 0;
@@ -230,6 +234,17 @@ static tool_output_file *GetOutputStream() {
   return Out;
 }
 
+static std::string DwarfDebugFlags;
+static void setDwarfDebugFlags(int argc, char **argv) {
+  if (!getenv("RC_DEBUG_OPTIONS"))
+    return;
+  for (int i = 0; i < argc; i++) {
+    DwarfDebugFlags += argv[i];
+    if (i + 1 < argc)
+      DwarfDebugFlags += " ";
+  }
+}
+
 static int AsLexInput(const char *ProgName) {
   OwningPtr<MemoryBuffer> BufferPtr;
   if (error_code ec = MemoryBuffer::getFileOrSTDIN(InputFilename, BufferPtr)) {
@@ -377,6 +392,10 @@ static int AssembleInput(const char *ProgName) {
   if (SaveTempLabels)
     Ctx.setAllowTemporaryLabels(false);
 
+  Ctx.setGenDwarfForAssembly(GenDwarfForAssembly);
+  if (!DwarfDebugFlags.empty()) 
+    Ctx.setDwarfDebugFlags(StringRef(DwarfDebugFlags));
+
   // Package up features to be passed to target/subtarget
   std::string FeaturesStr;
   if (MAttrs.size()) {
@@ -412,7 +431,7 @@ static int AssembleInput(const char *ProgName) {
                                            /*useCFI*/ true,
                                            /*useDwarfDirectory*/ true,
                                            IP, CE, MAB, ShowInst));
-                                           
+
   } else if (FileType == OFT_Null) {
     Str.reset(createNullStreamer(Ctx));
   } else {
@@ -502,6 +521,7 @@ int main(int argc, char **argv) {
 
   cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
   TripleName = Triple::normalize(TripleName);
+  setDwarfDebugFlags(argc, argv);
 
   switch (Action) {
   default: