MachO: direct-to-object attribute for data-in-code markers.

The target backend can support data-in-code load commands even when
the assembler doesn't, or vice-versa. Allow targets to opt-in for
direct-to-object.

PR13973.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164974 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 74f6dc6..b152a8c 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -139,6 +139,8 @@
 }
 
 void MCMachOStreamer::EmitDataRegion(DataRegionData::KindTy Kind) {
+  if (!getAssembler().getBackend().hasDataInCodeSupport())
+    return;
   // Create a temporary label to mark the start of the data region.
   MCSymbol *Start = getContext().CreateTempSymbol();
   EmitLabel(Start);
@@ -149,6 +151,8 @@
 }
 
 void MCMachOStreamer::EmitDataRegionEnd() {
+  if (!getAssembler().getBackend().hasDataInCodeSupport())
+    return;
   std::vector<DataRegionData> &Regions = getAssembler().getDataRegions();
   assert(Regions.size() && "Mismatched .end_data_region!");
   DataRegionData &Data = Regions.back();