4 files changed, 35 insertions, 3 deletions
diff --git a/include/llvm/MC/MCContext.h b/include/llvm/MC/MCContext.h
index e92d3b9e71..f6ae6479c5 100644
--- a/include/llvm/MC/MCContext.h
+++ b/include/llvm/MC/MCContext.h
@@ -129,6 +129,10 @@ namespace llvm {
     /// non-empty.
     StringRef DwarfDebugFlags;
 
+    /// The string to embed in as the dwarf AT_producer for the compile unit, if
+    /// non-empty.
+    StringRef DwarfDebugProducer;
+
     /// Honor temporary labels, this is useful for debugging semantic
     /// differences between temporary and non-temporary labels (primarily on
     /// Darwin).
@@ -346,6 +350,9 @@ namespace llvm {
     void setDwarfDebugFlags(StringRef S) { DwarfDebugFlags = S; }
     StringRef getDwarfDebugFlags() { return DwarfDebugFlags; }
 
+    void setDwarfDebugProducer(StringRef S) { DwarfDebugProducer = S; }
+    StringRef getDwarfDebugProducer() { return DwarfDebugProducer; }
+
     /// @}
 
     char *getSecureLogFile() { return SecureLogFile; }
diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 5691822e8e..74851ce140 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -638,9 +638,15 @@ static void EmitGenDwarfInfo(MCStreamer *MCOS,
   }
 
   // AT_producer, the version of the assembler tool.
-  MCOS->EmitBytes(StringRef("llvm-mc (based on LLVM "));
-  MCOS->EmitBytes(StringRef(PACKAGE_VERSION));
-  MCOS->EmitBytes(StringRef(")"));
+  StringRef DwarfDebugProducer = context.getDwarfDebugProducer();
+  if (!DwarfDebugProducer.empty()){
+    MCOS->EmitBytes(DwarfDebugProducer);
+  }
+  else {
+    MCOS->EmitBytes(StringRef("llvm-mc (based on LLVM "));
+    MCOS->EmitBytes(StringRef(PACKAGE_VERSION));
+    MCOS->EmitBytes(StringRef(")"));
+  }
   MCOS->EmitIntValue(0, 1); // NULL byte to terminate the string.
 
   // AT_language, a 4 byte value.  We use DW_LANG_Mips_Assembler as the dwarf2
diff --git a/test/MC/MachO/gen-dwarf-producer.s b/test/MC/MachO/gen-dwarf-producer.s
new file mode 100644
index 0000000000..7ccd78925e
--- /dev/null
+++ b/test/MC/MachO/gen-dwarf-producer.s
@@ -0,0 +1,8 @@
+// RUN: env DEBUG_PRODUCER="my producer" llvm-mc -g -triple i386-apple-darwin10 %s -filetype=obj -o %t
+// RUN: llvm-dwarfdump %t | FileCheck %s
+
+.globl _bar
+_bar:
+	ret
+
+// CHECK:    DW_AT_producer [DW_FORM_string]	("my producer")
diff --git a/tools/llvm-mc/llvm-mc.cpp b/tools/llvm-mc/llvm-mc.cpp
index e77f27e6dd..118dd4398d 100644
--- a/tools/llvm-mc/llvm-mc.cpp
+++ b/tools/llvm-mc/llvm-mc.cpp
@@ -236,6 +236,13 @@ static void setDwarfDebugFlags(int argc, char **argv) {
   }
 }
 
+static std::string DwarfDebugProducer;
+static void setDwarfDebugProducer(void) {
+  if(!getenv("DEBUG_PRODUCER"))
+    return;
+  DwarfDebugProducer += getenv("DEBUG_PRODUCER");
+}
+
 static int AsLexInput(SourceMgr &SrcMgr, MCAsmInfo &MAI, tool_output_file *Out) {
 
   AsmLexer Lexer(MAI);
@@ -353,6 +360,8 @@ int main(int argc, char **argv) {
   TripleName = Triple::normalize(TripleName);
   setDwarfDebugFlags(argc, argv);
 
+  setDwarfDebugProducer();
+
   const char *ProgName = argv[0];
   const Target *TheTarget = GetTarget(ProgName);
   if (!TheTarget)
@@ -393,6 +402,8 @@ int main(int argc, char **argv) {
   Ctx.setGenDwarfForAssembly(GenDwarfForAssembly);
   if (!DwarfDebugFlags.empty())
     Ctx.setDwarfDebugFlags(StringRef(DwarfDebugFlags));
+  if (!DwarfDebugProducer.empty())
+    Ctx.setDwarfDebugProducer(StringRef(DwarfDebugProducer));
   if (!DebugCompilationDir.empty())
     Ctx.setCompilationDir(DebugCompilationDir);
   if (!MainFileName.empty())