Index: include/llvm/MC/MCSubtargetInfo.h
===================================================================
--- include/llvm/MC/MCSubtargetInfo.h
+++ include/llvm/MC/MCSubtargetInfo.h
@@ -38,6 +38,9 @@
   const MCReadAdvanceEntry *ReadAdvanceTable;
   const MCSchedModel *CPUSchedModel;
 
+  // Members of this table have immature MC support
+  const char **MCImmaturityTable;
+
   const InstrStage *Stages;            // Instruction itinerary stages
   const unsigned *OperandCycles;       // Itinerary operand cycles
   const unsigned *ForwardingPaths;     // Forwarding paths
@@ -45,6 +48,8 @@
   unsigned NumProcs;                   // Number of processors
   uint64_t FeatureBits;                // Feature bits for current CPU + FS
 
+  bool HasMatureMCSupport; // MC Support is mature
+
 public:
   void InitMCSubtargetInfo(StringRef TT, StringRef CPU, StringRef FS,
                            const SubtargetFeatureKV *PF,
@@ -68,6 +73,14 @@
     return FeatureBits;
   }
 
+  /// hasMatureMCSupport - Return true if the MC support is considered to be
+  /// mature. MC support is mature when 'llc -filetype=obj' failing to handle
+  /// a piece of assembly (inline or otherwise) is considered a bug.
+  bool hasMatureMCSupport() const { return HasMatureMCSupport; }
+
+  // Determine MC layer maturity by target triple
+  bool getMCMaturity(StringRef TT) const;
+
   /// InitMCProcessorInfo - Set or change the CPU (optionally supplemented with
   /// feature string). Recompute feature bits and scheduling model.
   void InitMCProcessorInfo(StringRef CPU, StringRef FS);
Index: lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
===================================================================
--- lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
+++ lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
@@ -79,10 +79,11 @@
   if (isNullTerminated)
     Str = Str.substr(0, Str.size()-1);
 
-  // If the output streamer is actually a .s file, just emit the blob textually.
+  // If the output streamer does not have mature MC support, just emit the blob
+  // textually. Otherwise parse the asm and emit it via MC support.
   // This is useful in case the asm parser doesn't handle something but the
   // system assembler does.
-  if (OutStreamer.hasRawTextSupport()) {
+  if (!TM.getSubtarget<MCSubtargetInfo>().hasMatureMCSupport()) {
     OutStreamer.EmitRawText(Str);
     emitInlineAsmEnd(TM.getSubtarget<MCSubtargetInfo>(), 0);
     return;
Index: lib/MC/MCSubtargetInfo.cpp
===================================================================
--- lib/MC/MCSubtargetInfo.cpp
+++ lib/MC/MCSubtargetInfo.cpp
@@ -64,6 +64,8 @@
   NumFeatures = NF;
   NumProcs = NP;
 
+  HasMatureMCSupport = getMCMaturity(TT);
+
   InitMCProcessorInfo(CPU, FS);
 }
 
@@ -119,3 +121,27 @@
   InstrItins =
     InstrItineraryData(CPUSchedModel, Stages, OperandCycles, ForwardingPaths);
 }
+
+bool MCSubtargetInfo::getMCMaturity(StringRef TT) const {
+  // FIXME: There must be a better way than this
+  if (TT.startswith("aarch64-") ||
+      TT.startswith("arm-") ||
+      TT.startswith("armv") ||
+      TT.startswith("xscale-") ||
+      TT.startswith("i386-") ||
+      TT.startswith("i486-") ||
+      TT.startswith("i586-") ||
+      TT.startswith("i686-") ||
+      TT.startswith("i786-") ||
+      TT.startswith("i886-") ||
+      TT.startswith("i986-") ||
+      TT.startswith("amd64-") ||
+      TT.startswith("x86_64-") ||
+      TT.startswith("thumb-") ||
+      TT.startswith("thumbv"))
+    return true;
+
+  // Assume the MC layer is mature.
+  return false;
+}
+
Index: test/CodeGen/Generic/mature-mc-support.ll
===================================================================
--- /dev/null
+++ test/CodeGen/Generic/mature-mc-support.ll
@@ -0,0 +1,16 @@
+; Test that inline assembly is parsed by the MC layer when MC support is mature.
+
+; RUN: not llc -march=aarch64 < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=aarch64 -filetype=obj < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=arm < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=arm -filetype=obj < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=thumb < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=thumb -filetype=obj < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=x86 < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=x86 -filetype=obj < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=x86-64 < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=x86-64 -filetype=obj < %s 2>&1 | FileCheck %s
+
+module asm "	.this_directive_is_very_unlikely_to_exist"
+
+; CHECK: LLVM ERROR: Error parsing inline asm