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/MCAsmInfo.cpp b/lib/MC/MCAsmInfo.cpp
index 2456858..d9c1d51 100644
--- a/lib/MC/MCAsmInfo.cpp
+++ b/lib/MC/MCAsmInfo.cpp
@@ -50,6 +50,7 @@
   AllowNameToStartWithDigit = false;
   AllowPeriodsInName = true;
   AllowUTF8 = true;
+  UseDataRegionDirectives = false;
   ZeroDirective = "\t.zero\t";
   AsciiDirective = "\t.ascii\t";
   AscizDirective = "\t.asciz\t";
@@ -57,12 +58,6 @@
   Data16bitsDirective = "\t.short\t";
   Data32bitsDirective = "\t.long\t";
   Data64bitsDirective = "\t.quad\t";
-  DataBegin = "$d.";
-  CodeBegin = "$a.";
-  JT8Begin = "$d.";
-  JT16Begin = "$d.";
-  JT32Begin = "$d.";
-  SupportsDataRegions = false;
   SunStyleELFSectionSwitchSyntax = false;
   UsesELFSectionDirectiveForBSS = false;
   AlignDirective = "\t.align\t";