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
diff --git a/lib/MC/MCStreamer.cpp b/lib/MC/MCStreamer.cpp
index 43e62ff..e363f28 100644
--- a/lib/MC/MCStreamer.cpp
+++ b/lib/MC/MCStreamer.cpp
@@ -20,12 +20,9 @@
 #include <cstdlib>
 using namespace llvm;
 
-MCStreamer::MCStreamer(MCContext &Ctx) : Context(Ctx), EmitEHFrame(true),
-                                         EmitDebugFrame(false),
-                                         CurrentW64UnwindInfo(0),
-                                         LastSymbol(0),
-                                         UniqueCodeBeginSuffix(0),
-                                         UniqueDataBeginSuffix(0) {
+MCStreamer::MCStreamer(MCContext &Ctx)
+  : Context(Ctx), EmitEHFrame(true), EmitDebugFrame(false),
+    CurrentW64UnwindInfo(0), LastSymbol(0) {
   const MCSection *section = NULL;
   SectionStack.push_back(std::make_pair(section, section));
 }
@@ -183,85 +180,6 @@
   LastSymbol = Symbol;
 }
 
-void MCStreamer::EmitDataRegion() {
-  if (RegionIndicator == Data) return;
-
-  MCContext &Context = getContext();
-  const MCAsmInfo &MAI = Context.getAsmInfo();
-  if (!MAI.getSupportsDataRegions()) return;
-
-  // Generate a unique symbol name.
-  MCSymbol *NewSym = Context.GetOrCreateSymbol(MAI.getDataBeginLabelName() +
-                                               Twine(UniqueDataBeginSuffix++));
-  EmitLabel(NewSym);
-
-  RegionIndicator = Data;
-}
-
-void MCStreamer::EmitCodeRegion() {
-  if (RegionIndicator == Code) return;
-
-  MCContext &Context = getContext();
-  const MCAsmInfo &MAI = Context.getAsmInfo();
-  if (!MAI.getSupportsDataRegions()) return;
-
-  // Generate a unique symbol name.
-  MCSymbol *NewSym = Context.GetOrCreateSymbol(MAI.getCodeBeginLabelName() +
-                                               Twine(UniqueCodeBeginSuffix++));
-  EmitLabel(NewSym);
-
-  RegionIndicator = Code;
-}
-
-void MCStreamer::EmitJumpTable8Region() {
-  if (RegionIndicator == JumpTable8) return;
-
-  MCContext &Context = getContext();
-  const MCAsmInfo &MAI = Context.getAsmInfo();
-  if (!MAI.getSupportsDataRegions()) return;
-
-  // Generate a unique symbol name.
-  MCSymbol *NewSym =
-    Context.GetOrCreateSymbol(MAI.getJumpTable8BeginLabelName() +
-                              Twine(UniqueDataBeginSuffix++));
-  EmitLabel(NewSym);
-
-  RegionIndicator = JumpTable8;
-}
-
-void MCStreamer::EmitJumpTable16Region() {
-  if (RegionIndicator == JumpTable16) return;
-
-  MCContext &Context = getContext();
-  const MCAsmInfo &MAI = Context.getAsmInfo();
-  if (!MAI.getSupportsDataRegions()) return;
-
-  // Generate a unique symbol name.
-  MCSymbol *NewSym =
-    Context.GetOrCreateSymbol(MAI.getJumpTable16BeginLabelName() +
-                              Twine(UniqueDataBeginSuffix++));
-  EmitLabel(NewSym);
-
-  RegionIndicator = JumpTable16;
-}
-
-
-void MCStreamer::EmitJumpTable32Region() {
-  if (RegionIndicator == JumpTable32) return;
-
-  MCContext &Context = getContext();
-  const MCAsmInfo &MAI = Context.getAsmInfo();
-  if (!MAI.getSupportsDataRegions()) return;
-
-  // Generate a unique symbol name.
-  MCSymbol *NewSym =
-    Context.GetOrCreateSymbol(MAI.getJumpTable32BeginLabelName() +
-                              Twine(UniqueDataBeginSuffix++));
-  EmitLabel(NewSym);
-
-  RegionIndicator = JumpTable32;
-}
-
 void MCStreamer::EmitCompactUnwindEncoding(uint32_t CompactUnwindEncoding) {
   EnsureValidFrame();
   MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo();
@@ -283,7 +201,6 @@
   EmitCFIStartProcImpl(Frame);
 
   FrameInfos.push_back(Frame);
-  RegionIndicator = Code;
 }
 
 void MCStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {