6 files changed, 58 insertions, 5 deletions
diff --git a/include/llvm/MC/MCAsmInfoCOFF.h b/include/llvm/MC/MCAsmInfoCOFF.h
index a3ee1593c3..ba699d7852 100644
--- a/include/llvm/MC/MCAsmInfoCOFF.h
+++ b/include/llvm/MC/MCAsmInfoCOFF.h
@@ -18,6 +18,16 @@ namespace llvm {
     explicit MCAsmInfoCOFF();
       
   };
+
+  class MCAsmInfoMicrosoft : public MCAsmInfoCOFF {
+  protected:
+    explicit MCAsmInfoMicrosoft();
+  };
+
+  class MCAsmInfoGNUCOFF : public MCAsmInfoCOFF {
+  protected:
+    explicit MCAsmInfoGNUCOFF();
+  };
 }
 
 
diff --git a/lib/MC/MCAsmInfoCOFF.cpp b/lib/MC/MCAsmInfoCOFF.cpp
index 434d9103a7..6d34801f5c 100644
--- a/lib/MC/MCAsmInfoCOFF.cpp
+++ b/lib/MC/MCAsmInfoCOFF.cpp
@@ -38,3 +38,11 @@ MCAsmInfoCOFF::MCAsmInfoCOFF() {
 
   SupportsDataRegions = false;
 }
+
+MCAsmInfoMicrosoft::MCAsmInfoMicrosoft() {
+  AllowQuotesInName = true;
+}
+
+MCAsmInfoGNUCOFF::MCAsmInfoGNUCOFF() {
+
+}
diff --git a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
index 27031005bd..eb64ad112b 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
@@ -125,7 +125,19 @@ getNonexecutableStackSection(MCContext &Ctx) const {
                            0, SectionKind::getMetadata());
 }
 
-X86MCAsmInfoCOFF::X86MCAsmInfoCOFF(const Triple &Triple) {
+X86MCAsmInfoMicrosoft::X86MCAsmInfoMicrosoft(const Triple &Triple) {
+  if (Triple.getArch() == Triple::x86_64) {
+    GlobalPrefix = "";
+    PrivateGlobalPrefix = ".L";
+  }
+
+  AsmTransCBE = x86_asm_table;
+  AssemblerDialect = AsmWriterFlavor;
+
+  TextAlignFillValue = 0x90;
+}
+
+X86MCAsmInfoGNUCOFF::X86MCAsmInfoGNUCOFF(const Triple &Triple) {
   if (Triple.getArch() == Triple::x86_64) {
     GlobalPrefix = "";
     PrivateGlobalPrefix = ".L";
diff --git a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
index 2cd4c8eb30..5d619e8b17 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
+++ b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
@@ -38,8 +38,12 @@ namespace llvm {
     virtual const MCSection *getNonexecutableStackSection(MCContext &Ctx) const;
   };
 
-  struct X86MCAsmInfoCOFF : public MCAsmInfoCOFF {
-    explicit X86MCAsmInfoCOFF(const Triple &Triple);
+  struct X86MCAsmInfoMicrosoft : public MCAsmInfoMicrosoft {
+    explicit X86MCAsmInfoMicrosoft(const Triple &Triple);
+  };
+
+  struct X86MCAsmInfoGNUCOFF : public MCAsmInfoGNUCOFF {
+    explicit X86MCAsmInfoGNUCOFF(const Triple &Triple);
   };
 } // namespace llvm
 
diff --git a/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp b/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
index a8435152e2..f2a34edc5c 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
@@ -361,8 +361,10 @@ static MCAsmInfo *createX86MCAsmInfo(const Target &T, StringRef TT) {
       MAI = new X86_64MCAsmInfoDarwin(TheTriple);
     else
       MAI = new X86MCAsmInfoDarwin(TheTriple);
-  } else if (TheTriple.isOSWindows()) {
-    MAI = new X86MCAsmInfoCOFF(TheTriple);
+  } else if (TheTriple.getOS() == Triple::Win32) {
+    MAI = new X86MCAsmInfoMicrosoft(TheTriple);
+  } else if (TheTriple.getOS() == Triple::MinGW32 || TheTriple.getOS() == Triple::Cygwin) {
+    MAI = new X86MCAsmInfoGNUCOFF(TheTriple);
   } else {
     MAI = new X86ELFMCAsmInfo(TheTriple);
   }
diff --git a/test/MC/COFF/symbol-mangling.ll b/test/MC/COFF/symbol-mangling.ll
new file mode 100644
index 0000000000..f1b4b4becd
--- /dev/null
+++ b/test/MC/COFF/symbol-mangling.ll
@@ -0,0 +1,17 @@
+; The purpose of this test is to see if the MC layer properly handles symbol
+; names needing quoting on MS/Windows. This code is generated by clang when
+; using -cxx-abi microsoft.
+
+; RUN: llc -filetype=asm -mtriple i686-pc-win32 %s -o - | FileCheck %s
+
+; CHECK: ?sayhi@A@@QBEXXZ
+
+%struct.A = type {}
+
+define i32 @main() {
+entry:
+  tail call void @"\01?sayhi@A@@QBEXXZ"(%struct.A* null)
+  ret i32 0
+}
+
+declare void @"\01?sayhi@A@@QBEXXZ"(%struct.A*)