Refactor data-in-code annotations.

Use a dedicated MachO load command to annotate data-in-code regions.
This is the same format the linker produces for final executable images,
allowing consistency of representation and use of introspection tools
for both object and executable files.

Data-in-code regions are annotated via ".data_region"/".end_data_region"
directive pairs, with an optional region type.

data_region_directive := ".data_region" { region_type }
region_type := "jt8" | "jt16" | "jt32" | "jta32"
end_data_region_directive := ".end_data_region"

The previous handling of ARM-style "$d.*" labels was broken and has
been removed. Specifically, it didn't handle ARM vs. Thumb mode when
marking the end of the section.

rdar://11459456

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157062 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 16 insertions, 0 deletions

diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index 3ce84c2cd9..9497b6be49 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -138,6 +138,7 @@ public:
   virtual void EmitEHSymAttributes(const MCSymbol *Symbol,
                                    MCSymbol *EHSymbol);
   virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
+  virtual void EmitDataRegion(MCDataRegionType Kind);
   virtual void EmitThumbFunc(MCSymbol *Func);
 
   virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
@@ -352,6 +353,21 @@ void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitDataRegion(MCDataRegionType Kind) {
+  MCContext &Ctx = getContext();
+  const MCAsmInfo &MAI = Ctx.getAsmInfo();
+  if (!MAI.doesSupportDataRegionDirectives())
+    return;
+  switch (Kind) {
+  case MCDR_DataRegion:            OS << "\t.data_region"; break;
+  case MCDR_DataRegionJT8:         OS << "\t.data_region jt8"; break;
+  case MCDR_DataRegionJT16:        OS << "\t.data_region jt16"; break;
+  case MCDR_DataRegionJT32:        OS << "\t.data_region jt32"; break;
+  case MCDR_DataRegionEnd:         OS << "\t.end_data_region"; break;
+  }
+  EmitEOL();
+}
+
 void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) {
   // This needs to emit to a temporary string to get properly quoted
   // MCSymbols when they have spaces in them.