I cannot find a libgcc function for this builtin.  Therefor expanding it to a noop (which is how it use to be treated).  If someone who knows the x86 backend better than me could tell me how to get a lock prefix on an instruction, that would be nice to complete x86 support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47213 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 98165a2..d1538f3 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -210,6 +210,7 @@
   setOperationAction(ISD::STACKSAVE,          MVT::Other, Expand); 
   setOperationAction(ISD::STACKRESTORE,       MVT::Other, Expand);
   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32  , Expand);
+  setOperationAction(ISD::MEMBARRIER        , MVT::Other, Expand);
 
   if (!Subtarget->hasV6Ops()) {
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index d434eb9..334f6fe 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -2459,6 +2459,7 @@
         if (Function *F = CI->getCalledFunction())
           switch (F->getIntrinsicID()) {
           case Intrinsic::not_intrinsic:
+          case Intrinsic::memory_barrier:
           case Intrinsic::vastart:
           case Intrinsic::vacopy:
           case Intrinsic::vaend:
@@ -2544,6 +2545,9 @@
         WroteCallee = true;
         break;
       }
+      case Intrinsic::memory_barrier:
+        Out << "0; __sync_syncronize()";
+        return;
       case Intrinsic::vastart:
         Out << "0; ";
 
diff --git a/lib/Target/CellSPU/SPUISelLowering.cpp b/lib/Target/CellSPU/SPUISelLowering.cpp
index bfdb9e8..23c860a 100644
--- a/lib/Target/CellSPU/SPUISelLowering.cpp
+++ b/lib/Target/CellSPU/SPUISelLowering.cpp
@@ -181,7 +181,8 @@
   setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
   setOperationAction(ISD::MEMSET, MVT::Other, Expand);
   setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
-  
+  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
+
   // PowerPC has no SREM/UREM instructions
   setOperationAction(ISD::SREM, MVT::i32, Expand);
   setOperationAction(ISD::UREM, MVT::i32, Expand);
diff --git a/lib/Target/IA64/IA64ISelLowering.cpp b/lib/Target/IA64/IA64ISelLowering.cpp
index 6b9cf15..85db947 100644
--- a/lib/Target/IA64/IA64ISelLowering.cpp
+++ b/lib/Target/IA64/IA64ISelLowering.cpp
@@ -69,7 +69,8 @@
       setOperationAction(ISD::MEMMOVE          , MVT::Other, Expand);
       setOperationAction(ISD::MEMSET           , MVT::Other, Expand);
       setOperationAction(ISD::MEMCPY           , MVT::Other, Expand);
-      
+      setOperationAction(ISD::MEMBARRIER       , MVT::Other, Expand);
+
       setOperationAction(ISD::SINT_TO_FP       , MVT::i1   , Promote);
       setOperationAction(ISD::UINT_TO_FP       , MVT::i1   , Promote);
 
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index fa2f72c..ed76621 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -84,6 +84,7 @@
   setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
   setOperationAction(ISD::MEMSET, MVT::Other, Expand);
   setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
+  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
 
   setOperationAction(ISD::CTPOP, MVT::i32, Expand);
   setOperationAction(ISD::CTTZ , MVT::i32, Expand);
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 5ebc4c0..aa7396f 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -81,7 +81,8 @@
   setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
   setOperationAction(ISD::MEMSET, MVT::Other, Expand);
   setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
-  
+  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
+
   // PowerPC has no SREM/UREM instructions
   setOperationAction(ISD::SREM, MVT::i32, Expand);
   setOperationAction(ISD::UREM, MVT::i32, Expand);
diff --git a/lib/Target/Sparc/SparcISelDAGToDAG.cpp b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
index 8dd81b7..faa3d3b 100644
--- a/lib/Target/Sparc/SparcISelDAGToDAG.cpp
+++ b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
@@ -195,7 +195,8 @@
   setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
   setOperationAction(ISD::MEMSET, MVT::Other, Expand);
   setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
-  
+  setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand);
+
   setOperationAction(ISD::FSIN , MVT::f64, Expand);
   setOperationAction(ISD::FCOS , MVT::f64, Expand);
   setOperationAction(ISD::FREM , MVT::f64, Expand);
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 8ec8a5a..3e1f942 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -281,6 +281,10 @@
   setOperationAction(ISD::MEMSET          , MVT::Other, Custom);
   setOperationAction(ISD::MEMCPY          , MVT::Other, Custom);
 
+  if (!Subtarget->hasSSE2())
+    setOperationAction(ISD::MEMBARRIER    , MVT::Other, Expand);
+
+
   // Use the default ISD::LOCATION, ISD::DECLARE expansion.
   setOperationAction(ISD::LOCATION, MVT::Other, Expand);
   // FIXME - use subtarget debug flags